TW200306418A - Method and apparatuses for analyzing solder plating solutions - Google Patents

Abstract

The present invention relates to methods and apparatus for determining concentrations of various inorganic or organic components in solder plating solutions, which include titration or parallel titration methods, direct potentiometry methods, calibration methods, and/or UV-Vis absorption analysis.

Description

200306418 发明 Description of the invention [Technical field to which the invention belongs] The present invention relates to an analysis method and a device for welding ore solution, and in particular, it relates to a variety of components in the smelting solution; t valley welding plating solution and local fault welding ore solution. Method and device for concentration. [Prior art] In the manufacture of printed circuit boards, the conductive areas of the board are often electroplated with tin-coated paint, which is generally referred to as solder. This tin-lead paint facilitates the subsequent connection of electrical components' such as resistors, transistors, integrated circuits and the like to printed wiring boards. In addition, the increase in the use of integrated circuits requires the use of multilayer printed wiring boards having solder-plated through-holes for circuit connections on the layers of the board. High-lead solder is also used to connect a controlled removable wafer contact ("C4 wafer") to its substrate 'to relieve thermal stress and provide reliable contact between the wafer and the substrate. The C4 chip is designed to be used in a module with a low expansion substrate that minimizes the thermal stress generated. These modules are usually isolated and sealed from the environment to protect exposed chips. It is necessary to monitor the eutectic solder solution or high-lead solder solution 'commonly used in the electro-chemical deposition (ECD) of solder to ensure optimal efficiency. Specifically, changes in the concentration of inorganic components (such as acids, lead, and tin) and organic additives (such as polymeric nonionic surfactants, brighteners, and antioxidants) in this solder solution must be measured during the plating process. To achieve accurate and precise program control. However, the conventional method for determining the concentration of components in the solder plating solution is complicated and not reliable. 6 326 \ Patent Specification (Supplements) \ 92-〇5 \ 92] 04018 100306418 is reliable, and it will cause a high error rate. In addition, there is currently no automated on-line solder analysis tool available for automatic concentration analysis of the soldering solution, and most of the soldering solution analysis is still performed manually. In addition, the final processing of highly complex and expensive microcomputer wafers by solder plating requires strict control of the grooves. Therefore, it is an object of the present invention to provide a method for more quickly and accurately determining the concentration of components in a solder plating solution. Another object of the present invention is to provide an automatic on-line analysis tool for automatic concentration analysis of the soldering solution and an integrated analysis tool for automatically determining the concentration of all inorganic and organic components of the sample soldering solution. Other purposes and advantages will be made clearer by the subsequent disclosure and the scope of the accompanying patent application. [Summary of the Invention] One aspect of the present invention relates to a method for determining the acid concentration contained in a sample solder plating solution, which includes the following steps: (a) measuring the potential response of one or more calibration solutions of known acid concentration (B) measuring the correlation between the acid concentration of the solution and the potential response based on a calibration measurement; (c) measuring the potential response of the sample solder plating solution; and (d) based on the potential response measured in step (c) and The correlation measured in step (b) determines the acid concentration in the sample plating solution. Another aspect of the present invention relates to a method for determining the acid concentration contained in a sample solder plating solution, which includes the following steps: 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 "200306418 (a) provides a Sample solder plating solution with unknown acid concentration; (b) Titrate the sample solder plating solution with an alkali titrant; (c) Monitor the pH of the sample solder plating solution during the titration process, and terminate the titration procedure when the predetermined end point is reached, Among them, p 样品 of the sample welding ore solution at the predetermined end point is in a range from about 3.5 to 4.5; (d) Record the total amount of alkali titrant used to reach the predetermined end point; (e) Determine and The amount of titrant in which the tin ions in the sample solder plating solution react to form an insoluble tin compound; and (0 based on the total amount of titrant used, and if necessary based on the amount of titrant that reacts with the tin ions therein, Calculate the acid concentration in the sample solder plating solution. Another aspect of the present invention relates to a method for titrating the sample solder plating solution by using a titration solution containing a material selected from the group consisting of iodine and iodide, and This method measures the reduction oxidation potential response of such a sample solder plating solution, and determines the tin concentration in a sample solder plating solution containing tin and lead ions. Note that unless otherwise specified, the term "tin ions" described in the text refers only to Divalent Sn (II) ions, rather than tetravalent Sn (IV) ions. Another aspect of the present invention relates to a method for determining the lead concentration in a soldering solution of a sample containing tin and lead ions. It includes the following steps: (a) Determine the total metal concentration in the sample solder plating solution; (b) Determine the tin concentration in the sample solder plating solution as described previously; (c) Subtract the tin concentration from the total metal concentration And calculate the lead concentration in the sample solder plating solution 8 326 \ Patent Specification (Supplement) \ 92 · 05 \ 92104018 200306418. Yet another aspect of the present invention is a method for determining the lead concentration in the sample solder plating solution. Which includes the following steps: (a) measuring the potential response of one or more calibration solutions of known lead concentration; (b) determining the correlation between the lead concentration of the solution and the potential response based on the calibration measurement; (c) measuring the sample Electricity of soldering solution Bit response; and (d) determining the lead concentration in the sample solder plating solution based on the potential response measured in step (c) and the correlation measured in step (b). The invention further relates to a measurement sample solder plating A method for the concentration of lead in a solution, comprising the following steps: (a) adjusting the pH of the sample solder plating solution to a level ranging from about 4 to about 4.5; (b) adding EDTA by adding a continuous amount Titrate the sample solder plating solution with the main titration solution; (c) While performing step (b), monitor the pH of the sample solder plating solution after adding each amount of the main titration solution, and when in the sample solder plating solution When a drop in pH is observed, add a sufficient amount of the second titration solution to the sample solution to adjust the pH of the sample solution back to pH 之前 before adding the next amount of the main titration solution; (d) when further added The main titration solution can no longer cause the end of the titration procedure when the pH of the sample solder plating solution drops; (e) Record the total volume of the second titration solution used, and if necessary 9 326 \ Patent Specification (Supplement) \ 92 -05 \ 921 〇4〇18 200306418 To record the end of the titration The total volume of the main titration solution; and (0 based on the total volume of the second titration solution used, determine the lead concentration in the sample solder plating solution; (g) if necessary, based on the total volume of the main titration solution that reached the end of the titration , Determine the total metal concentration in the sample solder plating solution. Another aspect of the present invention relates to a potential self-adjusting method for measuring the concentration of a polymerized nonionic surfactant in a soldering solution of a sample by measuring the following parameters: (a) generating a plating current The time required for the infinite increase; or (b) a signal selected from an analysis including a plating current and a stripping charge measured during the infinite increase of the plating current. Another aspect of the present invention relates to a potentiometric titration method for determining the concentration of a polymeric nonionic surfactant in a sample plating solution, which includes the following steps: (a) adding the titration solution to the sample solution; The lead-polymeric nonionic surfactant complex forms an insoluble reaction product and titrates the sample solder plating solution; (b) Detects the titration end point of the sample titration procedure in step (a), and records that the titration is reached The amount of titration solution used at the end point; (o provides a plurality of standard solder plating solutions containing a polymeric nonionic surfactant at a unique known concentration; (d) titrates a plurality of standard solder plating solutions by using a titration solution, and 10 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 Detect the end point of titration of each of multiple standard soldering solutions, (e) Calculate the volume of the titration solution and the Polymeric nonionic surfactant concentration produces an experimental titration factor that is correlated; and (f) based on the volume of the titration solution recorded in step (b) and the experimental titre calculated in step (e) Factor to determine the concentration of polymerized non-ionic surfactants in the sample solder plating solution. Another aspect of the present invention relates to a method for measuring the sample solder plating solution in The absorbance at a wavelength in the range of about 3 9 3 nm (nm) to about 413 nm, and the brightener concentration in the sample solder plating solution is calculated based on the absorbance at these wavelengths, and the sample solder plating solution is measured. A method for increasing the concentration of a brightener. Another aspect of the present invention relates to a method for determining an antioxidant concentration in a sample solder plating solution, which includes the following steps: (a) adding an acid solution to the sample solder plating solution To increase the pH of the sample soldering solution to a predetermined value; (b) monitor the redox potential of the sample soldering solution before and after adding the acid solution; (c) measure the value of the sample soldering solution by adding The redox potential is plotted as a function of pH 値 to produce a redox potential response curve; and (d) the redox potential response curve of the sample solder plating solution is analyzed to determine the Antioxidant concentration. Another aspect of the present invention relates to a method for determining the antioxidant concentration of 11 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 in a sample plating solution. Derivatives of antioxidants detected by ultraviolet-visible spectroscopy and UV-visible absorption analysis at a wavelength that maximizes the UV absorbance of such antioxidant derivatives to determine the antioxidant concentration in the sample solder plating solution Another aspect of the present invention relates to a method for determining the concentration of an antioxidant in a sample solder plating solution, which includes directly performing the UV-visible of the solder plating solution at a wavelength that maximizes the UV absorbance of the antioxidant. Absorption analysis, and the step of determining the antioxidant concentration in the sample solder plating solution based on the results of the UV-visible absorption analysis. Yet another aspect of the present invention relates to an optical unit for performing spectroscopic analysis of one or more test solutions, which includes: a first fluid chamber of a first capacity; a connection for introducing one or more test solutions One or more fluid inlets to the first fluid chamber; a second fluid chamber of a second capacity connected to the first fluid chamber, wherein the second capacity is smaller than the first capacity; a connection for discharging one or more test solutions A fluid outlet to the second fluid chamber; a fluid mixing device for mixing one or more test solutions in the first and / or second fluid chamber as needed; irradiation for irradiating light into the second fluid chamber Light source; a light detector connected to the illuminating light source for detecting light transmitted or emitted by one or more test solutions in the second fluid chamber; and for collecting the one or more test solutions as needed Absorption spectrum, and 12 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 A computing device connected to a light detector based on which spectral analysis is performed. Another aspect of the present invention relates to a method for determining the component concentration in a sample plating solution based on Raman spectroscopy. Other aspects, features, and specific examples of the present invention will become clearer from the following disclosure and the scope of the accompanying patent application. [Embodiment] The present invention proposes to automatically analyze the inorganic components (including acids, tin and lead) and organic components (including polymerized nonionic surfactants, Various methods and devices for brightener and antioxidant) concentrations are described in detail in the following paragraphs. Total acid analysis conventionally uses an acid-base titration method to determine the end point of all methane sulfonic acid (MS A) neutralized by an alkali titrant by titrating the sample plating solution with an alkali titrant. The total acid (ie, methanesulfonic acid) concentration in the plating solution. The end point is usually indicated by the color change exhibited by the formulations contained in the sample solution. Phenol presents a color change when ρ Η approaches or approaches 8.0. However, as the pH of the sampled plating solution of the titrated sample rises, dissolved metal components such as S η 2 + and P b 2 + are disregarded regardless of the titrant (eg, hydroxide, carbonate, and amine), buffer Whatever the type of agent or electrolyte, they are continuously precipitated from the sample solution. When the precipitates of Sn (〇H) 2 and Pb (〇H) 2 are generated, more titrant will be needed to reach the end point, which will cause the MSA concentration reading to be higher than the actual MSA concentration. Precipitation causes errors in conventional acid-base titration methods. Tin (sn 2 +) is particularly sensitive to the formation of hydroxides 326 \ Patent Specification (Supplements) \ 92-〇5 \ 92】 04018 200306418, which starts at low ρ Η 値 (ie, P Η > 1) The lead solution can be titrated as long as pH 7 before any hydroxide precipitation begins. In order to avoid the problems faced by the conventional acid-base titration method described above, the present invention proposes the following novel methods for measuring the total acid concentration: I. Direct potential method The direct potential technique proposed by the present invention includes direct measurement of the sample solder plating solution. Potential, and the total acid concentration in this sample solder plating solution was determined based on potential measurement. Specifically, the present invention uses the following steps to determine the total acid concentration in a sample plating solution: (a) providing one or more calibration solutions containing methanesulfonic acid at a known, specific concentration; (b) measuring such The potential response of the calibration solution and the correlation between the acid concentration and the potential response determined based on the calibration measurement; (c) measuring the potential response of the sample solder plating solution; and (d) based on the potential response measured in step (c) And the correlation measured in step (b) to determine the acid concentration in the sample solder plating solution. It is preferred that the sample plating solution be diluted before any measurements are taken. The purpose of diluting the sample solder plating solution is to make the ρ 此种 of this solution be in the range from about 1 to 3 'and preferably close to 2 (7 mM). Under this ρ Η 値, there is no hydrolysis of metal ions in the sample solution, and the potential response measured by the glass electrode is Nernstian, which improves the reliability of the potential measurement. For example, a sample solution can be added to deionized water (eg, 50 or 100 ml) by adding a sample solution (eg, 1 or 2 ml), or contain 15 14 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 to 25 vol% KN 0 3 in deionized water. KNO 3 is used here as an ionic strength buffer to minimize the interference from tin and lead during the measurement of acid concentration. (A). Direct potential method based on standard addition: A specific specific example of the direct potential method proposed by the present invention uses the following steps to determine the acid concentration in the sample solder plating solution: First, measure the acid concentrated solution according to the following equation (where Potential response of two consecutive standards with known acid concentration added to deionized water (preferably deionized water containing 20% by volume potassium nitrate), and the slope k ·. E a-E i k- -log 2 five of which are the potential response measured after the second standard addition of acid concentrate is introduced into deionized water, and the first standard addition of acid concentrate is introduced into deionized water Potential response measured afterwards. The slope ir thus measured indicates the correlation between the acid concentration in the solution and the potential response. A glass electrode can then be used to measure the potential of the sample solder plating solution. It is better to dilute the sample solder plating solution before the potential measurement. For example, the sample solution can be diluted 1/50 with deionized water (deionized water containing 20% by volume of KNO3 is preferred). Next, the standard addition of the acid concentrate was added to the diluted sample plating solution, and the potential of the sample plating solution with the standard addition was measured. In order to make the estimated acid concentration in the diluted sample solution larger due to this standard addition 15 326 \ Patent Specification (Supplement) \ 92 · 05 \ 92104018

Ci > = 200306418 It is better to control the standard addition in a doubling manner. ° Then, the acid concentration of the sample can be calculated according to the following simplified equation:

V A CA

Vs [anti \ og {{E7-E \) I k)-\] where C, is the acid concentration in the sample solder plating solution, is the standard added volume of the acid concentrate in the plating solution, and ^ is the standard acid Concentration, h is the volume of the diluted sample solder plating solution, ^ different from the dilution sample solder plating solution measured before and after the standard addition. The foregoing method for determining the total acid concentration in the plating solution is a relative standard deviation of less than ± 5%, and more specifically, it is lower than (B). Direct potential method based on potential increase: proposed by the present invention Another specific specific example of the potentiometry method is to determine the acid concentration in the sample plating solution: a predetermined current is passed through two Pt electrodes immersed in an alkali solution. The alkali solution contains, in addition to methanesulfonic acid, to be measured. All ingredients of the sample. The potential between these two Pt electrodes is measured. Usually the time (for example, 20 to about 40 seconds, preferably about 30 seconds) monitors the potential of the two p t to make the two Pt electrodes reach an equilibrium state, and it is more readable. Then, a specific amount of the sample plating solution to be measured is added to the alkali, a predetermined current is again passed between the two Pt electrodes, and the potential of the solution is measured. 326 \ Patent Specification (Supplements) \ 92-05 \ 92104018 Total in liquid to sample welding In the standard addition of anti-A system potential The general response is in the soil 1 · 5%. Use the following step i between the plating solution and the solution with sufficient potential between the electrodes. Test / Sample 16 200306418 As shown in Figure 1, the potential measured after the sample solution was added to the alkaline solution showed a substantial increase compared to the measured potential before the sample solution was added. This increase in potential is proportional to the acid concentration in the sample solution and can be used to determine the acid concentration in the sample solution. For example, a calibration solution containing methanesulfonic acid at a known, specific concentration can be prepared, and the potential increase caused by the addition of such a calibration solution can be measured to produce a display potential increase as the acid concentration in the solder plating solution Calibration curve as a function of. Fig. 1 shows a plurality of potential response curves according to the method described above, of which six are measured with a sample soldering solution and one is measured with a calibration solution. It is obvious from Fig. 1 that the measured potential response to the sample plating solution is highly reproducible, and the increase in potential exhibited by the measurement of each sample is consistent. By comparing the potential increase caused by the addition of the sample solder plating solution to the potential increase caused by the calibration solution, the acid concentration in the sample solder plating solution can be determined. The following table shows the measurement of the six methanesulfonic acid concentrations in the sample solution based on the potential increase according to the aforementioned technique: 17 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 Table 1 Experiment # Measured Methanesulfonic acid concentration (g / L) 1 5.226009 2 4.689542 3 4.61905 4 4.605715 5 4.72701 6 4.598907 Average 4.65 standard deviation 0.05 Relative standard deviation 1.10% π. Incomplete titration The method used in the present invention is used to determine the sample solder plating solution The incomplete titration technique of the total acid concentration includes arbitrarily selecting a titration endpoint having a pH value in a range from about 3.5 to about 4.5, more preferably in a range from about 3.8 to about 4.4, and about 4 The pH is best. Specifically, the incomplete titration technique of the present invention includes the following steps: (a) providing a sample solder plating solution having an unknown acid concentration; (b) titrating such a sample solder plating solution using an alkali titrant; (c) using the The p Η probe continuously monitors the ρ Η 値 of this type of sample plating solution during the titration process; (d) terminates the titration procedure when the predetermined end point is reached, where in this pre-18 326 \ Patent Specification (Supplement) \ 92- 05 \ 92104018 200306418 At a fixed endpoint, the pH of the sample soldering solution ranges from about 3.5 to about 4.5; (e) Record the total amount of titrant used to reach the predetermined endpoint; (f) Determine as required The amount of titrant that reacts with tin ions in this sample solder ore solution to form an insoluble tin compound; and (g) based on the total amount of titrant used and, if necessary, based on the titration with tin ions in it The amount of flux was used to calculate the acid concentration in the sample solder plating solution. Alkali titrants that can be used to perform incomplete titration methods as described above include, but are not limited to, NaOH, KOH, and ethanolamine. The difference between the incomplete titration method of the present invention and the conventional acid-base titration method lies in that most of the methanesulfonic acid in the sample solder plating solution has been selected and reacted with the strong base titrant and thus recovered. The lead ion did not start the end point of the titration of Shen Yuan. Instead of making the titration procedure until the pΗ 値 of the sample solder plating solution reaches about 7, and the lead point of the lead ions in the solution begins to precipitate and cause measurement errors, the incomplete titration method of the present invention starts from about 3.5 The titration procedure is terminated at a selected endpoint defined by ρ η 値 in the range of about 4 · 5 to maximize the recovery of methanesulfonic acid, and at the same time, reduce the concentration of the given ion in the titration process in the sample welding solution. At least. The selected end point of the titration according to the present invention is characterized in that the pIi 値 of the sample solder plating solution in the range from about 3.8 to about 4.4 is better, and about 4 is better. At PH4, more than 99% of the methanesulfonic acid in the sample solder plating solution reacted with the strong base titrant and was recovered ', but the lead ions did not start to precipitate from the solution, so the titration process was not disturbed by lead. 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Since the tin ions in the solder plating solution of the sample to be titrated have a high affinity for hydroxide even at pH 値 2, tin ions (sn 2 Inevitably, it will react with strong alkali titrant to form tin hydroxide (sn (〇H) 2) precipitate, which will affect the consumption of alkali titrant. However, due to the formation of Sn (〇H): hydrogen The consumption of oxides is stoichiometric based on the following chemical reactions, so the effects of tin ions can be easily corrected:

Sn2 + + 2〇H · = Sn (〇H) 2 | Therefore, by measuring the amount of tin ions in the sample solution according to the method described below, the amount of titrant consumed by tin ions alone can be easily determined, And subtract it from the total amount of titrant used to obtain the amount of titrant used to neutralize and recover methanesulfonic acid in the sample solder plating solution. Fig. 2 shows a titration curve of methanesulfonic acid measured in the incomplete titration procedure of the present invention as described above. It is obvious that the more KOH titrant is added to the sample solder plating solution, the greater the recovery rate of methanesulfonic acid. At pH 4, methanesulfonic acid recovery was about 99%. Total acid analysis was performed using the incomplete titration method described above. The test contains three standard solutions of methanesulfonic acid at various known concentrations, and the test results are as follows: 20 326 \ Patent Specification (Supplement) \ 92-05 \ 92 KM018 200306418 Table 2 Total acid analysis using incomplete titration Result Standard solution # 1 # 2 # 3 Concentration (g / 1) 50 60 70 Measurement result (g / 1) 50.52 60.00 69.93 50.65 60.39 69.76 50.88 60.27 70.08 49.90 60.22 69.95 50.7 1 60.1 3 69.80 Average 50.53 60.20 69.90% standard deviation 0.74 % 0.24% 0.18% Tin analysis The present invention uses an oxidation-reduction potential (ORP) titration procedure to determine the tin concentration in a sample solder plating solution containing both tin and lead ions, which includes titrating such a sample solution with a titrant solution, and The step of monitoring the ORP response of the sample plating solution during the titration. Various titration solutions can be used to produce an ORP response indicative of the tin concentration in the sample solution. Such a titration solution preferably contains iodine or iodide. I. Iodometric Titration Using a Stabilizing Solution A specific embodiment of the present invention relates to the determination of tin concentration in a sample solder plating solution using an iodine titration technique, which includes the following steps: (a) adding a stabilization solution to the sample solder plating 'In the solution' to stabilize the lead ions therein and prevent the lead ions from precipitating during the subsequent dropping 21 326 \ Patent Specification (Supplements) \ 92-05 \ 921〇4〇18 200306418; (b) using iodine-containing Titration solution to titrate the sample solder plating solution; (c) monitor the redox potential of the sample solder plating solution during the iodine titration process to determine the end of the titration procedure; and (d) based on the end point of the titration measured in step (c) Calculate the tin concentration in the sample solder plating solution. It is better to dilute the sample solder plating solution in deionized water before adding the stabilization solution. The stabilizing solution used in the present invention may include ethylenediaminetetraacetate (EDTA), which is mismatched with lead ions in the solder plating solution to prevent lead ions from precipitating with iodine in the subsequent iodine titration. The stabilization solution preferably contains both EDTA and ammonium acetate. The function of acetic acid is to adjust the P 婷 of the sample Ting Mine 丨 Valley Liquid to 4 so that the lead ions therein can be effectively wrong with EDTA. Together. The tin ions in the diluted sample solder plating solution were then titrated with a titration solution containing iodine. The tin ions in the solder plating solution and the iodine in the titration solution undergo the following redox reactions: 12 Seven Sn2 + — Seven Sn4 + Therefore, the redox of the sample solder plating solution can be easily monitored by using the ORP electrode in the iodine titration procedure. Potential (ORP) to determine the end of the titration, in which all + 2 tin ions in the solder plating solution are oxidized to + 4 valence. Once the volume and iodine concentration of the titration solution used to reach this end point are known, the amount of tin ions in the sample solder plating solution can be easily determined. Generally, for the analysis of tin concentration in the eutectic welding bath, a sample of 1 ml is required. 22 326 \ Patent Specification (Supplement) \ 92-05 \ 921〇4〇18 200306418 for iodine titration analysis, and for high lead soldering The plating tank 'requires 5 ml of sample. The iodine solution may also contain a small amount of potassium iodide (κι) to preserve its iodine. The lead ions in the sample plating solution are stabilized by using EDTA or EDTA / acetate buffer solution. This EDTA or EDTA / acetate buffer solution is mismatched with the lead ions in the plating solution to prevent lead ions in subsequent iodine Precipitation with iodine during titration. Figure 3 shows examples of multiple iodine titration response curves. These titration response curves are made for a number of solder plating solutions that contain tin at a concentration above or below the ideal control point (approximately 3.10 g / liter) in the high lead solder plating solution. On this iodine titration curve, when dV / dVol titrant = 0 (which is reflected in the inflection point on the titration curve), the reaction between Sn 2 + and 12 is completed. Therefore, if the volume of the iodine titration solution used at this inflection point is known, the total amount of tin ions in the sample solder plating solution can be determined. Note that a second inflection point occurs approximately 0.05 ml after the first inflection point, which may be caused by the reaction of the sample solution's antioxidant or brightener with iodine. In a preferred embodiment, the present invention uses a dual-polarized platinum electrode to detect the end point of the titration in such an iodine titration procedure. The use of a dual uranium electrode in the present invention facilitates the automatic cleaning of the analytical unit and the electrodes via an electrolytic process that passes through a conductive electrolyte, and solves the problem of electrode passivation commonly encountered in systems using other types of electrodes. Specifically, a dual uranium electrode as shown in FIGS. 4A and 4B of the present application can be used, which includes a device that can be connected to a potential measuring device, and serves as a redox 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 23 200306418 The first electrode of an electric potential (ORP) electrode, and the second auxiliary electrode separately used to generate electrolytic gas. In a general state, the first electrode is connected to a potential measuring device for ORP measurement of the sample solder plating solution, as shown in FIG. 4A. In the ORP measurement interval, the first electrode is separated from the potential measuring device and is connected to the current source (having an operating voltage of about 5-1 2 V AC) together with the second auxiliary electrode, as shown in Fig. 4B. Both the first and second electrodes are then immersed in a conductive electrolyte solution. Current passes through the first and second electrodes and the electrolyte solution, generates gas (shown as air bubbles in FIG. 4B), and provides a strong stripping of any deposits on the electrode surface that will passivate the electrode response to potential changes Surface procedures. Figure 5 shows the titration curve measured for iodine titration of tin ions using a dual platinum electrode as previously described. The ORP response shows the titration endpoint that can be easily determined. II. Iodine titration with pre-titration removal of lead ions Another specific embodiment of the present invention relates to an iodine titration technique for pre-titration of lead ions from a sample solder plating solution, which includes the following steps: (a) Precipitation of lead A flux is added to the sample solder plating solution to form an insoluble compound with the lead ions therein, and the lead ions are removed from the sample solder plating solution; (b) The sample solder plating solution is titrated with a titration solution containing iodine; ( 〇 monitor the redox potential of the sample solder plating solution during the iodine titration to determine the end point of the titration; and (d) calculate the tin concentration in the sample solder plating solution based on the end point of the titration measured in step (c). Before adding the lead precipitant, it is better to dilute the sample solder plating solution in deionized water 24 326 \ Patent Specification (Supplement) \ 92-05 \ 921〇4〇18 200306418. The lead precipitant used in the present invention may include Any chemical compound that reacts with lead ions in the sample solder plating solution to form an insoluble precipitate, the limitation is that this chemical compound will not cause the precipitation of tin ions, and the results of tin titration have Little or no effect. This lead precipitant is preferably selected from the group consisting of HC1, NaCl, KC1 and mixtures thereof. The concentration of this lead precipitant in the solution is from about 20 to about 45 weight percent. Hydrochloric acid (HC1) is more preferred, and the concentration is most preferably from about 35 to about 40 weight percent. This lead precipitant may also contain potassium chloride or chlorinated solution in a concentration of from about 1M to about 3M Sodium (KC1 or NaCl), and a concentration of about 2M is better. Figure 6 shows the iodine titration curve of tin with lead ions removed from the sample solution using HC1 before the titration procedure and the iodine titration curve of lead ions stabilized with EDTA Figure 7 shows another tin-iodine titration curve using KC1 to remove lead ions from the sample solution before the titration procedure. After the lead ions were removed from the sample solder plating solution before the iodine titration, the titration results appeared larger Reproducibility and linearity, and less electrode cleaning is required. Figure 8 shows the results of a series of 24 tin-iodide titrations performed as described above for the pre-titration of lead ions. The total standard deviation is approximately 5%. No ORP was performed in these titration tests Extremely clean. However, after 14 tests, the titration results began to deviate from the original titration results, which showed that after about 14 titrations, the ORP needs to be cleaned. After about 22 titration tests, the ORP was cleaned with a paper towel. Electrode, and the titration results immediately return to the range of the original titration results. 25 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Figure 9 shows the pre-titration removal of lead ions as described above using a ramp function The linearity of the four iodine titration results. Good linearity appears between the volume of the sample solder plating solution and the volume of iodine titrant used. Lead analysis I. Subtraction method The determination of lead concentration can be determined by first measuring the sample solder plating solution. The total metal concentration, and then using the aforementioned method to determine the tin concentration in such a sample solution, so that the lead concentration can be measured indirectly by subtracting the tin concentration from the total metal concentration. The total metal concentration can be determined by a titration method. Specifically, an excessive amount of a complexing agent such as EDTA is added to a better diluted sample solder plating solution, where the complexing agent forms a complex with metal ions (that is, both tin and lead ions). The EDTA / ammonium acetate solution is used as a complexing agent, so that EDTA forms a complex with tin and lead ions, and ammonium acetate adjusts the pH of the solution to more than 4 preferably. A titration solution (which preferably contains copper sulfate) is then used to titrate the excess EDTA in the sample solder plating solution that is not mismatched with metal ions. Sensors such as ion selective electrode (ISE), photometric sensor or temperature sensor can be used to monitor CuS04 titration to determine that all excess EDTA is consumed by copper sulfate End of the titration. Then the total amount of EDTA added minus the amount of copper sulfate used in the titration 'to produce an amount of EDTA that is actually mismatched with tin and lead ions in the sample solder plating solution, and the total metal in the sample solder plating solution is determined concentration. The tin ion concentration in the sample solder plating solution can be measured separately and independently using the various methods described above in the "Tin Content 26 326 \ Patent Specification (Supplements) \ 92-05 \ 92104018 200306418 Analysis". The lead concentration can then be measured by subtracting the tin concentration from the total metal concentration. II. Direct potentiometric method The lead concentration can also be directly measured using a direct potentiometric method similar to that described for the determination of acid concentration, which includes the following steps: (a) measuring the potential response of one or more calibration solutions of known lead concentration; (b) Determining the correlation between the lead concentration in the solution and the potential response based on the calibration measurement; measuring the potential response of the sample solder plating solution; and based on the potential response measured in step (c) and measured in step (b) The correlation was determined to determine the lead concentration in the sample solder ore solution. It is better to dilute the sample solder plating solution before making any measurements. For example, the sample solution can be added to deionized water or concentrated electrolyte solution to maintain the pH of the sample solder plating solution above 3 (there is a more stable potential response from the electrode), and Dilute the sample solution. A specific example of the present invention is based on the direct potential method described above. The following steps are used to determine the lead concentration in the sample solder plating solution: First, the lead concentrate is measured using a lead ion selective electrode according to the following equation (which has known lead). Potential response of two consecutive standards added to deionized water, and the slope was determined to be 1:

Ejj-Εΐ k 2-log 2 Five of them are "measured after introducing the second standard addition of lead concentrate to deionization 27 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 The potential response is the potential response measured after introducing the first standard addition of lead concentrate to deionized water. The slope thus measured! It indicates the correlation between the lead concentration in the solution and the potential response. · The potential of the sample solder plating solution can then be measured using a lead ion selective electrode. It is better to dilute the sample solder plating solution before potential measurement. For example, the sample solution can be diluted 1/100 with deionized water. Next, the standard addition of the lead concentrate was added to the diluted sample soldering solution, and the potential of the sample soldering solution with the standard addition was measured using a lead ion selective electrode. It is better to control the amount of standard addition in such a way that the estimated lead concentration in the diluted sample solution is approximately doubled due to such standard addition. Then the total lead concentration in the sample solder plating solution can be calculated according to the following simplified equation:

Va Ca

Cl: -------

Vs [anti log ((^ 2- £,) / 1) -1] where 0 is the lead ion concentration in the sample solder plating solution, and h is the standard added volume of the lead concentrate added to the sample solder plating solution. Based on the lead concentration in the standard addition, the volume of the diluted sample solder plating solution '仏 and & are the potential responses of the diluted sample solder plating solution measured before and after the standard addition of the lead concentrate, respectively. The initial experiment to determine the lead concentration in a high-lead sample soldering solution (without tin) at a p Η 値 below 3 showed unsatisfactory results due to electrode instability in this highly acidic environment. Therefore, we hope to keep the PY dimension 28 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 higher than 3 'as quantified in Table 3 below, there is a more stable potential response from the electrode: Table 3 Electrode response from high lead sample solder solution (without tin) P Η = 1. 9 p Η > 3 (with acetate buffer) True concentration measurement Concentration response True concentration measurement Concentration response pH (g / L) Degree (G / L) Should (mV) (g / L) Degree (g / L) Should (mV) 75 100 3 75 8 1 8 3.4 65 68.70 8 3.4 76 75 10 5 65 70 10 5 85 97 10 5 Included The effect of test tin (4 g liter) on the concentration of lead in a sample solder solution with a high lead concentration (75 g / L). It has been observed that the electrode potential response takes a long time to reach stability and drifts after a period of time. The measured concentration of lead is 9 1.36 g / liter, and the error rate is 2 1.8%. Repeated measurements resulted in similarly high lead concentrations. One way to reduce the error rate of the foregoing lead concentration measurement is to reduce the effect of the difference in the activity coefficient between the sample solder plating solution and the standard addition by diluting the sample solder plating solution in a concentrated electrolyte solution. When analyzing eutectic sample solder plating solutions with higher tin concentrations than lead concentrations, dilution of the sample solder plating solution is even more necessary. III. Parallel Titration 29 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 The present invention proposes a parallel titration method for directly determining the wrong concentration in the sample solder plating solution, which uses an EDTAZ main titration A second titration solution containing a strong base, and preferably a metal hydroxide such as Na ◦ Η or κOH. EDTA (ethylene diamine tetraacetic acid) is a polyfunctional acid that forms a very strong complex with metal ions in the sample plating solution and releases protons. The released protons cause a detectable change in the pH of the sample plating solution, and it can be monitored by a pH probe. Therefore, the present invention uses a main titration solution containing EDTA to be mismatched with metal ions in the sample solder plating solution, and uses a glass pH probe to monitor the pH change of the sample solution caused by the addition of EDTA. In addition, the present invention uses a second titration solution containing a strong test, such as NaOH or KOH, to neutralize the protons released after each addition of EDTA, to compensate for the pH change caused by the protons released, and to ensure that the samples are plated. The pH of the solution was the same as before each EDTA addition. In this way, the glass pH probe accurately measures and records the pH drop caused by each EDTA addition, and each pH drop thus measured and recorded has the same "starting point", so they can be compared with each other. Specifically, the parallel titration method of the present invention begins with the step of conditioning the sample soldering solution by adjusting p Η 値 of such a sample soldering solution to a base 値 'in a range from about 4 to about 4.5. On this basis, the tin ions in the sample solder plating solution are already in the form of insoluble tin hydroxide (S η (〇η) 2) ', so the sample solution appears slightly milky. The pH of the sample solder plating solution can be adjusted by using an alkaline solution containing hydroxide ions (0H ·), such as NaOH or KOH. 30 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Alternatively, the aforementioned incomplete titration method can be used first to analyze the total acid concentration of the sample solution, during which the pH of the sample welding ore solution is titrated to about 4 ' So that the sample solder plating solution can be used directly for lead concentration analysis according to the parallel titration method described later without any sample conditioning or pH adjustment steps. During the tin-EDTA complex process, the protons released by EDTA were immediately neutralized by hydroxide ions from tin hydroxide, so that the pH was not detected by the glass pH probe immersed in the sample solder plating solution. The pH value of the sample solder plating solution was maintained at the aforementioned base value. The chemical reaction in this step is as follows:

Sn (〇H) 2+ H2EDTA — SnEDTA + 2H2〇 On the other hand, at a pH range of about 4 to 4.5, lead ions are not like tin ions, and they are not in the form of hydroxides. The protons released by EDTA during the process are not neutralized, which will cause an immediate pH drop in the sample solder plating solution that can be detected and recorded by the pH probe immersed in it. The chemical reaction in this step is as follows:

Pb2 + + H2EDTA — PbEDTA + 2H + is used to quantify the pH drop caused by the addition of each EDTA during the lead-EDTA hybridization process. After each EDTA is added, a second titration solution containing hydroxide ions is added to the sample welding In the solution, the protons released by EDTA are neutralized and the sample solder plating solution is titrated back to the aforementioned pH-based tritium. Such a second titration solution may contain one or more strong test compounds such as Na O Η and / or KO Η. After adding this second titration solution after the addition of each EDTA, the pH of the sample solder plating solution and the lead-EDTA hybrid process will be in the next 31 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 EDTA addition It is the same as before (that is, equal to the base), so that the pH drop caused by the addition of each EDTA can be easily quantified and compared with each other. Another advantage of this titrated release of protons is that the addition of EDTA in portions and titration of the protons so released will ensure that the pH of the solution will not decrease to the point that it will cause the precipitation of EDTA complexes (EDTA and complexes become lesser as the pH decreases Dissolved) of low 値. A continuously reduced amount of EDTA was added to the sample solder plating solution so as to coincide with the lead ions therein, and the pH drop caused by each EDTA addition was measured using a pH probe and recorded. In addition, monitor and record the total amount of EDTA added and the total amount of the second titration solution. After all lead ions in the sample solder plating solution are mismatched with EDTA, further adding EDTA to it will not mismatch with metal ions, and no protons are released by EDTA, so the pH is not immersed in the sample solution. The probe detected a drop in pH. Therefore, despite the continuous addition of EDTA, detecting the constant pH of the sample soldering solution can still signal the end of the lead-EDTA interaction. Fig. 10 illustrates the relationship between the pH value of the sample solder plating solution, the EDTA added to it, and the second titration solution containing 0% in the parallel titration process described above. During the tin-EDTA incorporation process, regardless of whether EDTA is continuously added, the pH of the sample solder plating solution is maintained at the same base. When the tin-EDTA co-operation ends and the lead-EDTA co-operation starts, each EDTA addition causes the pH of the sample solder plating solution to drop due to the protons released by the EDTA. Next, after each EDTA solution, a second titration solution containing 0Η was added to the sample solder plating solution, and the released protons were neutralized and the pH of the sample solution was adjusted back to base 値. When the lead-EDTA co-operation ends, further addition of EDTA will no longer cause the pH of the sample solder plating solution to drop, showing that lead 32 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418-EDTA co-operation End point and no additional second titration solution is required. Therefore, by recording the total amount of addition, the lead concentration in the sample solder plating solution can be measured directly and independently without any correction. Figure 11 shows the multiple titration curves prepared for the sample solder plating solution according to the aforementioned parallel titration method. When the initial pH drop in the sample solution is detected, the pH of the sample solder plating solution is reduced to EDTA. Add volume as a function of plot. As shown in Figure 11, during the lead-EDTA hybrid process, each addition of EDTA will cause the pH of the sample solder plating solution to drop. However, after the lead-EDTA complex, the flat end of the titration curve, such as "Indicates that the addition of EDTA no longer causes a drop in pH. Figure 12 shows multiple titration curves plotting the added volume of NaOH (i.e. the second titration solution) as a function of the added EDTA. After each EDTA was added, NaOH was added to the sample solder plating solution to neutralize the protons released and adjust the pH of the sample solution to pH 値. As shown in Fig. 12, the ratio of NaOH: EDTA during the lead-EDTA hybridization process is approximately 2: 1. After the lead-EDTA complex, as indicated by the flat "tail" of the titration curve, no NaOH solution was added. Since only NaOH is used in the lead-EDTA complex process, and the consumption of NaOH is stoichiometric relative to the lead concentration in the sample solution, the total volume of NaOH used in the parallel titration procedure can be used to Directly calculate the lead concentration in the sample solder plating solution. Analysis of Polymeric Nonionic Surfactants I. Potential Self-Adjustment Method A specific example of the present invention uses a potential self-adjustment method to determine the concentration of polymerized nonionic surfactants in a solder plating solution. 33 326 \ Patent Specification (Supplement) \ 92 · 05 \ 92104018 200306418 In a co-fusion welding plating solution containing a polymeric nonionic surfactant at a concentration ranging from 0 to 26 ml / Fe (CVS 'cyc 1 icv ο 11 amm 〇gramssca η) was measured in a cyclic voltammeter collected at a scan rate of 100 millivolts per second at an electrode rotation speed of rpm. When the electrode position is applied, the energy can be compared with Ag. When the / AgCl reference electrode is between -0.5 and -0.6 volts, a considerable current stagnation is observed to the diffusion limit. This diffusion-limited current stagnation is stable and reproducible, depending only slightly on the electrode potential. This diffusion-limited current stagnation may be caused by a potential-independent diffusion process, with metal cations penetrating through the adsorption surface layer on the electrode. At a greater negative electrode potential, an infinite increase in the plating current occurs, which persists in the anode portion of the voltammetry measurement scan. This infinite current increase may be caused by the transition from the "smooth" stage to the "dendritic" stage on the electrode surface during metal growth. The inventors of the present invention have found that the time required for the transition from the stagnation-limited current stagnation to the infinite increase in the plating current depends on the electrode potential applied to the electrode and the concentration of the organic polymeric nonionic surfactant in the sample solder plating solution . When the applied electrode potential is maintained constant, this transition time is related to the concentration of the polymerized nonionic surfactant in the sample solder plating solution, and therefore it can be used for the analysis of the polymerized nonionic surfactant. On the other hand, the inventors have found that the analytical signal (such as plating current or stripped charge) measured during the period when the infinite plating current increase occurs strongly depends on the concentration of the polymerized nonionic surfactant in the solder plating solution. . In fact, when a polymeric nonionic surfactant was titrated into the inorganic matrix of the solder plating solution, an S-shaped correlation similar to the conventional titration curve was observed. 34 326 \ Patent Specification (Supplement) \ 92-05 \ 92〗 040] 8 200306418 Therefore, by monitoring the analysis signal during the infinite increase of the plating current, the polymerized nonionic surface activity in the solder ore solution can be easily determined剂 浓 量。 Agent concentration. Both linear potential scanning analysis and potential step plating stripping analysis can be used to measure the analysis signal during the period when such an unlimited increase in the electric ore current occurs. In this kind of measurement, the anode limit of the potential region is more negative than the saturated calomel electrode (SCE) for Ag / AgCl, which is more than +0.1 volt. Electroplating potentials in the range from about -0.60 to -0.70 volts relative to Ag / AgCl are generally suitable for measuring the concentration of polymerized nonionic surfactants having a concentration of 0.5 to 2 ml / liter. It is better to use stripped charge instead of electroplating current as the analysis signal, because the use of stripped charge will reduce the noise and reduce the interference caused by hydrogen evolution and oxygen reduction. It is better to use regularization to strip the charge. It is preferable to perform each plating cycle with a plating time of about 15 seconds, or a plating time of about 2 to 5 seconds. The stripping potential is preferably about -0.15 volts relative to Ag / AgCl. To avoid large anode currents (1000 milliamps), a smaller stripping potential of about -0.25 volts or -0.3 volts relative to Ag / AgCl can be used. In order to optimize the measurement results of the present invention, a series of optimization tests were performed. For linear potential scanning analysis, the optimal parameters were found to be: cathode limit -65 0 ± 25 mV, scan rate 50400 mV / sec, and end point of 0.7 7 〇 in the eutectic welding plating solution, where The sample was titrated into the eutectic plating solution. For potential step electroplating stripping analysis, the best parameters were found to be: plating potential -6 2 5 ± 2 5 millivolts, plating time 2-5 seconds, stripping potential-3 0 0 35 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 04018 200306418 or -150 millivolts, and the end point in the eutectic plating solution is 0-60. The measurement temperature is preferably in a range from about 30 to 45 ° C. The optimization test of the present invention is performed at 36.6 ° C, but a clearer inflection point can be obtained at higher temperatures such as 40-45 ° C. When the temperature rises to about 50 ° C, the titration curve shows an unclear transition, so it is desirable to control the measured temperature below 50 ° C. 11. Potentiometric titration method Another specific example of the present invention uses a potentiometric titration method to determine the concentration of a polymerized nonionic surfactant in a solder plating solution. Polymeric nonionic surfactants used in solder plating solutions are generally polyethers or polyalkylene glycols. Such nonionic surfactants can form weak complexes with large metal ions, such as barium, and thus become cationic. Since the solder plating solution contains a large amount of lead ions that can form a cationic complex with the polymerized nonionic surfactant therein, it is not necessary to introduce additional metal ions in the present invention. Therefore, in the present invention, an insoluble reaction product can be formed by adding a tetraphenyl sodium borate titrant solution to the sample solder plating solution to form a lead / polymeric nonionic surfactant complex in the sample solution. And directly perform potentiometric titration. The endpoint of this potential titration can be easily detected by a surfactant electrode. Commercially available surfactant electrodes suitable for practicing the invention are available from Orion Research Inc. (Boston, MA). Since the reaction between the lead / polymeric nonionic surfactant complex and the sodium tetraphenylborate titrant is not stoichiometric, it is necessary to pass a number of standard solder platings at known polymerized nonionic surfactant concentrations 36 326 \ Patent Specification (Supplement) \ 92 · 〇5 \ 92 on the solution 04018 200306418 Multiple potentiometric titration measurements were performed to make the volume of sodium tetraphenylborate titrant used and the polymerization non-ionicity in the plating solution Surfactant concentrations are correlated, while experimental titration factors are established. Potentiometric titration provides a fast and simple method for the analysis of polymeric nonionic surfactants, and produces reproducible and reliable measurement results. Brightener analysis I. Ultraviolet-visible spectroscopy A specific example of the present invention uses ultraviolet-visible spectroscopy to determine the brightener concentration in a soldering solution. The first step in the UV-visible spectrum analysis is to determine the appropriate wavelength of incident UV light that maximizes the absorption achieved by the brightener. In order to find such an appropriate wavelength, the UV-visible absorption spectra of various test solutions were measured: (1) a solution containing methanesulfonic acid (MS A) and a brightener; (2) a solution containing MS A, brightening Solution of agent and tin ion; (3) solution containing MSA, brightener, tin ion and lead ion; (4) solution containing MSA, brightener, tin ion, lead ion and antioxidant; and (5) A solution containing MSA, brighteners, tin ions, lead ions, antioxidants, and polymeric nonionic surfactants. Fig. 13 shows the ultraviolet-visible absorption spectrum measured for the aforementioned test solution. Solutions containing only MSA and brightener exhibit a single absorption peak at a wavelength of about 345 nm, while solutions containing tin ions other than MSA and brightener exhibit a single absorption at a different wavelength of about 403 nm Absorption peaks. Therefore, the addition of tin ions shifts the absorption peak by about 60 nm 'which can be attributed to the formation of tin / brightener complexes. The effect of the addition of lead ions on the position of the absorption peak is minimal. 37 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 A solution containing MSA, a brightener, tin and lead ions, and an antioxidant exhibits two absorption peaks, one at a wavelength of about 276 nm, And another at a wavelength of about 40 3 nm. Similarly, a solution containing MSA, a brightener, tin and lead ions, an antioxidant, and a polymeric nonionic surfactant exhibited two absorption peaks at a wavelength of 276 nm and a wavelength of 403 nm, respectively. The second absorption peak at 403 nm is due to the tin / brightener complex, while the first absorption peak at 276 nm is due to the polymeric nonionic surfactant. And antioxidants. Therefore, about 403 ± 10 nm, preferably 403 nm ± 5 nm, and a more preferable wavelength of 4 10 nm are used for UV-visible spectrum analysis of the brightener concentration in the soldering solution. The incident UV light is provided by a UV light source, which is preferably a super bright white LED. A filter is placed between the UV light source and the analysis chamber containing the solder plating solution of the sample to be analyzed, and this filter can only be made to have an appropriate range (that is, about 403 ± 10 nm, with 403 nm ± 5 nm is preferred, and 410 nm is more preferred. A UV detector is placed on the other side of the analysis chamber opposite to the UV light source and filter to measure the amount of UV light passing through the analysis chamber and determine the amount of UV light absorbed by the sample plating solution in the analysis chamber. The amount of UV light. According to Beer's law, the absorbance / varies with the concentration c of a particular species in the solution, and the linear relationship between the absorbance / and the concentration ^ is as follows: ^ ^ xbxc where ε is the Mohr absorption coefficient of the species, And the path length of the sample is 38 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 (that is, the path length of the light analysis tube in which the sample is contained). However, 'Beer's law is accurate only for appropriately diluted solutions. Fluctuations in measured absorbance were observed in high-concentration solder plating solutions, while in highly diluted solder plating solutions, due to background interference from eutectic solder plating solutions and brighteners in such diluted solder plating solutions The small absorption coefficient ε appeared, so no absorbance was observed. Therefore, it is desirable to dilute the solder plating solution with deionized water before UV-visible measurement. For a nominal eutectic solder plating solution (with a brightener concentration of 5 ml / litre) or a high lead solder plating solution, the dilution ratio is preferably within the range of 1 to 00. In a specific embodiment of the present invention, a standard addition of a known concentration of a brightener is continuously added to a standard eutectic solder solution containing only inorganic components and not containing any polymeric nonionic surfactants or antioxidants. . The absorbance at approximately 4 10 nm is then added to each standard to produce a linear calibration curve by plotting the concentration of the brightener as a function of the measured absorbance. It can then be measured at similar wavelengths, approximately 4 10 nm, including all ingredients, including organic additives (approximately 100 ml / L of polymeric nonionic surfactant, 5 ml / L of brightener, and 10 ml / L of Antioxidant) Co-welding solution of the sample. By using the calibration curve prepared before, the brightener concentration in the sample eutectic welding solution can be easily determined. Figure 14 shows three individual calibration curves made for brightener analysis, which show good reproducibility of the aforementioned UV-visible spectroscopy method. These calibration curves have excellent linearity and show very little drift. 39 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 In another specific example of the present invention, the extrapolation method is used for UV-visible spectrum analysis and determination of the concentration of the brightener. Specifically, the extrapolation method includes the following steps: First, a sample including all ingredients containing organic additives (ie, polymeric nonionic surfactants, brighteners, and antioxidants) is measured at a wavelength of about 4 10 nm. The absorbance of the eutectic welding plating solution was recorded as. A standard addition of a known concentration of a brightener is then continuously added to the sample plating solution. The absorbance of this sample solution after the standard addition of each brightener was measured and recorded continuously as Z Z2Z;, ... The concentration of the brightener in this sample solution after each standard addition is also calculated, and it is continuously recorded as C /, C :, C), ..., as shown in Figure 15. Then, a linear calibration curve can be prepared by plotting the brightener concentrations C; ,, C ;, ... into a linear function of the absorbances Z 7, Z 2z j, ..., as shown in FIG. 15. By extrapolating this linear calibration curve back to intersect the y-axis (shown as the concentration axis), a y-intercept 値 is obtained. The absolute y-intercept for y-intercept shown in Figure 15 indicates the original brightener concentration in the sample solder plating solution before any standard additions were introduced. The above-mentioned extrapolation method minimizes the difference between the sample solder plating solution and the calibration solution. By adding the standard addition of the brightener directly to the sample solder plating solution, it can eliminate the possible existence of polymerized nonionic surfactants and antioxidants in the sample solder plating solution and the absence of such polymerized compounds in the calibration solution. Potential measurement caused by ionic surfactants and antioxidants--! 〇 δ Wu Ai. The aforementioned analytical method for determining the concentration of brighteners may have errors caused by degradation of the standard brightener 40 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 solution. Figure 16 shows a comparison of the initial measurement results obtained using a fresh standard brightener solution and the measurement results obtained after using the same standard solution but leaving these standard solutions to stand for a specific period of three days. It is obvious that when the time passes, subsequent measurement results drift away from the initial results slowly. It is believed that degradation of standard brightener solutions can be measured to cause the formation of particles in the soldering solution, which directly affects the absorbance of such solutions and causes measurement errors. Figure 17 shows various absorption calibration curves made using standard brightener solutions of the same concentration but different aging. Specifically, a calibration curve and (1) will be prepared using a fresh standard brightener solution labeled "Danbury fresh std" purchased from Advanced Technology Materials, Inc. ("ATMI") (Danbury, CT) Calibration curve prepared by using shaken standard brightener solution provided by ATMI and labeled "Danbury 5 day old std-shake", and (2) by using ATMI provided and A comparison of calibration curves made with a standard brightener solution that is labeled "Danbury 5 day old std-settled" without shaking (ie, settling) and aged for 5 days. The "Danbury 5 day old std-settled" calibration curve has an absorbance approximately 25% lower than the "Danbury fresh std" calibration curve, and the "Danbury 5 day old std-shake" calibration curve has an absorbance approximately 2 0 higher than the "D anburyfreshstd" curve. %. In addition, a calibration curve prepared by using a fresh standard brightener solution purchased from AMD Saxony Manufacturing GmbH ("AMD") ("Dresden, Saxony") and labeled "Dresden fresh std" will be prepared using the 41 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Comparison of calibration curves made with standard brightener solution provided by AMD and not labeled "Dresden 13 day std-shake" for 1 to 3 days . The absorbance of the calibration curve “D 1 · e s d e η 1 3 d a y s t d · s h a k e” is approximately 20% higher than the calibration curve of “D r s d d e n f r e s h s t d”. Therefore, in order to prevent the loss of accuracy caused by the degradation of the standard brightener solution or the generation of particles due to such degradation, it is better to use the freshly prepared brightener solution in the standard addition. Alternatively, it is better to use a filtering mechanism to filter out the particles generated in the brightener solution. Antioxidant analysis The antioxidant used in the soldering plating solution is a catechol species, which is provided as an antioxidant in the eutectic soldering plating solution, and prevents the oxidation of Sn + 2 to 〇 4 4 S π. The present invention proposes two Methods for measuring the concentration of the antioxidant in the solder plating solution include a redox potential method and ultraviolet-visible spectroscopy as discussed later. I. Redox potential (0 R P) method Antioxidants (ie catechol) usually undergo redox reactions in solution according to the following equation:

According to the principle of Le Chatelier5s, the acidity of a catechol solution will affect the redox potential of the solution. Therefore, a specific example of the present invention is 42 326 \ Patent Specification (Supplement) \ 92-05 \ 921040] 8 200306418 The redox potential electrode is used to monitor the redox potential response of the sample during acid titration. Specifically, 1 or 2 ml of a ρ Η I plating solution having about -1 was added to 100 ml of deionized water 'so that the pH of the diluted sample solution was about 1. An oxidation-reduction potential (ORP) electrode was used to dilute the oxidation-reduction potential of the sample solder plating solution. An acid titration solution (for example, E to a diluted sample solder plating solution) that is compatible with the solder plating solution (that is, the acid does not form irreversible products with the solder plating components) The pH 値 is increased to a predetermined value to change the acidity of the sample welding solution. The ORP electrode is used to measure the redox potential of the sample during this acid titration, and the redox potential is plotted as a function of the pH 焊 of the sample during the acid titration process. It is used to make redox wires. Based on the measurement described above, the oxidation of the sample solder plating solution should also be measured on the slope of the curve. This slope is then compared to the redox potential response curve of several solutions of known antioxidant concentrations. Slope comparison, the concentration of antioxidants in the solder plating solution. Figure 18 shows a graph plotting the redox measured on the sample solder plating solution as a linear function of the pH of this sample solution. The area contains three displays A graph of the calibration curve of the solutionized reduction potential response to three known antioxidant concentrations. II. UV-Vis spectroscopy method Another specific example of the present invention uses purple Outside-Visible spectroscopy technology at 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 Welding ore solution I spoon sample Welding product Plating solution measured by the plating solution after adding the plating solution The position response of the solution is measured by the original potential response calibration calibration plating to measure the sample (position response 3 1 9 shows the measured oxygen • determination 43 200306418 antioxidant concentration in the mineral solution. UV-visible spectroscopy can be derived by detecting the antioxidant Or by directly detecting the antioxidant molecules in the solder plating solution. I. Antioxidant-Iron Complex A specific embodiment of the present invention includes the use of ferric chloride to form an antioxidant with Blue complex with a maximum absorbance of about 0 nm and detectable by UV-visible spectroscopy. This antioxidant-iron complex decomposes in water in about 5-20 minutes, but is stable in a methanol solution Adding pyridine to a methanol solution reduces the transient period of color development, increases the maximum extinction coefficient by about 3-5 times, and shifts the absorption maximum ochre blue to 600 nm. Therefore, the present invention uses FeCh / pyridine / methanol Solution in Antioxidants in the plating solution are mismatched. For example, '0-45 0 micron standard antioxidants can be added to a methanol solution containing 12.5 mM Hou steep and 7. 5 mM iron chloride. Experimental results show this standard Antioxidants After mixing the antioxidants with the Fe c 3 / pyridine / methanol solution, 'a linear calibration curve with stable absorbance readings was generated within 2 minutes. UV-visible absorbance readings were made using an antioxidant extracted from an aqueous solder plating solution' It is better to eliminate the adverse effects of the solution matrix. It is better to use acetic acid acetate to extract the antioxidant in the self-soldering plating solution. Figure 20 shows that the aqueous solution of the newly prepared antioxidant ·· μ is added to 25 grams ( (35 ml) Two calibration curves marked with squares were prepared by containing 12.5 mM pyridine and 7.5 mM FeCl: in FeCh / N-dine / methanol solution in methanol. The calibration curve marked with a solid square is measured at a wavelength of about 5 8 5 nm 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 040] 8 44 200306418, and the calibration curve marked with a hollow square is Measured at a wavelength of about 7 1 5 nm. Both curves show a linear absorption response. Figure 20 also shows two calibration curves marked with dots (empty or solid) without extracting antioxidants from fresh eutectic samples prepared using pure antioxidant solutions using ethyl acetate. Specifically, 10 ml of each sample was extracted with 2 ml of ethyl acetate, and 0.1 ml of the extract was injected into 25 g (35 ml) of FeCh / pyridine containing 12.5 mM pyridine and 7.5 mM FeCh in methanol. / Methanol solution. The calibration curve indicated by the solid dots is measured at a wavelength of about 585 nm, and the calibration curve indicated by the hollow dots is measured at a wavelength of about 715 nm. Both calibration curves, indicated by dots (hollow or solid), show a linear absorption response. In addition, the slope of the calibration curve indicated by the dots obtained by using the extracted antioxidant is equal to 95% of the slope of the calibration curve indicated by the square obtained by using the fresh antioxidant solution, which indicates that the extraction of the antioxidant is quantitative. . Figure 20 further includes two calibration curves indicated by triangles by extracting the antioxidant concentration of Solderon® SC antioxidants sold by Shipley Ronal (Marlborough, MA) with ethyl acetate. The horizontal coordinates of the data points are calculated assuming that S ο 1 d e r ο n ® S C antioxidant concentrate has a catechol concentration of about 1 μ. In a preferred embodiment of the present application, the UV-visible spectrum analysis of the nominal eutectic sample described above can be performed in an automatic analyzer, and the extraction and analysis of antioxidants can be performed in this automatic analyzer. In the photometric unit. Generally, about 10 ml of the sample plating solution is used for UV-visible spectrum analysis in this automatic analyzer, and the sample plating solution is added with ethyl acetate 45 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 The total volume of the solution is approximately 15 ml. After extraction with ethyl acetate, approximately 3 ml of the antioxidant extract was injected into the photometric unit for automatic UV-visible spectrum analysis. It is better to fill the photometric unit with about 16 ml of FeCh / pyridine / methanol solution to measure the reference light intensity (ie, the reference measurement) of the solution. Approximately 6 ml of the FeCh / pyridine / methanol solution was used to transfer 0.3 ml of the antioxidant extract into the photometric unit. The antioxidant / FeCl 3 / pyridine / methanol mixture solution was stirred for about 4 5-50 seconds and allowed to settle for about 4 5-50 seconds, and then the photometric reading of this mixture solution was performed. Table 4 below shows the results of UV-Vis analysis using various washing steps including: (1) non-washing, (2) washing with 10 ml of FeCh / pyridine / methanol solution, and (3) using 20 ml of FeC13 / pyridine / methanol solution washes. 46 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418

Measurement of light intensity and absorbance using different washing methods # 1 Non-washing method # 2 Before introducing the reference solution into the unit, use 10 ml of FeCh / pyridine / methanol to wash the photometric unit method # 3 After introducing the reference solution Use 20 ml FeCh / pyridine / methanol to wash the photometric unit method before entering the unit. # Reference light intensity is 90 seconds after the sample intensity at 600 nm and the sample absorbance at 90 seconds after the injection is 180 seconds after the injection. Sample absorbance at 600nm and 180 seconds after injection # 1 5.520 1.830 0.479 1.110 0.697 # 2 4.43 1.462 0.481 1.105 0.603 4.13 1.308 0.499 0.95 0.638 # 3 4.39 1.165 0.576 0.8 15 0.731 4.38 1.366 0.506 0.965 0.657 RSD 7.8 7.8 % 7.5% The measurement results show that the absorbance of the samples measured with or without the washing step is quite consistent, with a relative standard deviation (RSD) of only 7.8%. Π. Antioxidant-molybdenum complex 47 326 \ Patent Specification (Supplement) \ 92-05 \ 921〇4〇18 200306418 Another specific example of the present invention includes the use of molybdate ions to form antioxidants and can be easily used Antioxidant-molybdenum complex of yellow-orange color measured by ultraviolet and visible spectroscopy. First, the wavelength at which the antioxidant-molybdenum complex exhibited the maximum absorbance was measured using a complex solution containing molybdenum dioxide, ammonium acetate and EDTA. Pure antioxidants were added to this complex solution, and the ultraviolet-visible spectrum of the solution was measured, as shown in Figure 21. The antioxidant-molybdenum complex shows a maximum absorbance in a range from about 280 nm to about 32.0 nm and at a wavelength of about 300 nm. Figure 22 shows the measured absorbance response for a MoO2Ch / NH4C2H302 / EDTA solution as a function of the volume of pure antioxidant added to this solution. The absorbance response of a solution shows a linear relationship with the concentration of the antioxidant in the solution (that is, the volume of the antioxidant added to such a solution), which conforms to Beer's law. An antioxidant-molybdenum complex can be formed using a complex solution containing 0.005M molybdenum dichloride, 1.5M ammonium acetate, and 0.1M EDTA, and the measurement results using this complex solution show good reproducibility. However, at high molybdenum concentrations, absorption measurements can drift significantly, reducing the accuracy of UV-visible spectrum analysis. This drift can be reduced by diluting the MoO2Ch / NH4C2H3O2 / EDTA solution 4 or 5 times with water and 2M ethanolamine solution. Experiments have shown that this dilution can effectively reduce the drift of the absorption measurement to about 0.0 2 absorbance units (AU) over a 5 minute period. In a specific example, 15 ml of Mo 〇2C12 / 48 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 040] 8 200306418 NH4C2H3〇2 / EDTA sample and 1.5 ml of sample were used Ultraviolet analysis of the concentration of antioxidants in high-line high-lead solder plating solutions (containing Sn, Pb, MSA, and concentrated liters of antioxidants). Using 0.5 ml of antioxidant diluted in water and adding 0.2 5 ml of pure ethanolamine, as shown in Figure 23, the relationship between the concentration of the antioxidant and the measured absorbance was determined. The determination of the concentration of the antioxidant in the sample welding solution was made from The tin, lead and brighteners in this sample solution accurately measure the antioxidant concentration. III. Direct UV-Vis Spectroscopy of Antioxidants Measurement of Antioxidants in Sample Welding Solution by UV-Vis Spectroscopy at 276 ± 20nm In particular, i-pieces, photometer plates and UV detection devices to generate and transmit: short-wavelength UV light. First, it is better to set a small, cheap and long-life UV light source with a broad spectrum wavelength from about 200 nm to about 2500 nm, and more preferably about 5,000 nm, with low power consumption. That is, it requires no more than 5 and more than 2 watts, and it draws no more than 2 amps. The tip is better than 1 ampere. It can be an onboard transformer. This UV light source has a minimum of 30 mJ / pulse. Very good, at least 40 mJ / pulse, and at least 25 transmit frequencies, at least 50 Hz. This u V light source 3: 26 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018 The lead ore solution is injected into about 10ml / visible spectrum, and an additional calibration curve is added to measure it. The method can overcome the scene interference, and can directly detect the concentration of the agent by spectral technology. The UV optics used here are used to measure and detect this UV light source from 160nm to. The power of such U V light watts does not have a peak current and is not easily supplied. The emission intensity is also smaller than the height of Hertz (Η z). 49 200306418 has a cross-sectional area of no more than 2 square decimeters (dm 2), more preferably no more than 1 square decimeters, and no more than 0.5 Square decimeters are best. The effective life of this U V light source is preferably at least 10 pulses, and more preferably at least 10 s pulses. This U V light source has a shorter warm-up time, that is, no more than 5 seconds, more preferably no more than 1 second, and no more than 0.5 seconds. One of the most preferred UV light sources suitable for implementing the present invention is the RSL 3 1 00 series xenon compact flashlight manufactured by PerkinElmer, Inc. (Wellesley, MA). Other suitable UV light sources having the aforementioned operating characteristics may also be used in the practice of the present invention. Second, a filter that selectively transmits UV light with a wavelength of around 276 nm (ie, 27 6 ± 20 nm) and blocks UV light at other wavelengths is used to provide a filter with a wavelength of 2 7 6 ± 20 nm A single beam of UV light at a wavelength of meters. Particularly suitable for implementing a group of filters of the present invention is a narrow band interference filter manufactured by MK Photonics, Inc. (Albuquerque, NM). This narrowband filter from MK Photonics selectively transmits a wavelength centered at 276 nm and a full-width half-maximum of ± 6 nm (full-width 1 ^ 1; ^) 1 ^ 乂 丨 11111111,? \ ¥ 11] \ 4) and 20% of the smallest peak transmitted 1] ¥ light. Another set of filters that can be used to implement the present invention is a broadband filter manufactured by Acton Research Co., Ltd. (A c t ο η, M A). This broadband filter from A ct ο η R esearch C ο ρ ο rati ◦ η selectively transmits a wavelength centered at 276 nm, a FWHM of ± 40 nm, and a minimum spike of 50% Transmitted UV light. Note that the choice of filter depends on the maximum absorption wavelength of the target species (its antioxidant is 276 nm, but it can be higher or lower for other target species), and the disclosure here is only based on Illustrative, however, it is not intended to limit the broad scope of this application in any way. 50 326 \ Patent Specification (Supplements) \ 92-05 \ 921040] 8 200306418. In other words, other types of filters provided by other manufacturers can be easily used to implement the present invention, consistent with the disclosure herein. The filter used in the present invention is susceptible to degradation, which causes the optical characteristics and performance of such a filter to change significantly over time. For example, Figure 24 shows a plot of the transmittance of an unused filter as a function of the wavelength of UV light transmitted by the filter, and the transmittance and transmission wavelength of the filter after 3 months of use A comparative graph showing that degradation of a filter can cause significant changes in the wavelength and transmittance of UV light transmitted by such a filter. Therefore, regular maintenance of the filter at least once a month is better. Third, it is necessary to use a transparent optical material that is transparent to UV light, especially UV light having a wavelength of about 276 nm, to transmit the filtered UV light to the sample solution to be analyzed, and then to the detection device. Optical fiber is particularly good for the present invention, and it can be added to a special adapter for transferring the U V light source to the optical unit. Low hydroxyl fibers are better, and three different fiber sizes can be used to reduce or increase light intensity, including 400 microns, 600 microns, and 1000 microns. SMA 905 polymorphic connectors for single fiber connections are best for forming such adapters. In addition, an optically transparent fluorinated ethylene propylene (FEP) tape with an adhesive backing having a thickness of about 0.011 inches can be used on UV optical elements, which will provide the durability of expensive UV optical elements And reduce the frequency of regular maintenance of such UV optics. Figures 25 and 26 show a novel photometer plate specially designed for ultraviolet-visible spectrum measurement at a short wavelength of about 276 nm, which can measure the dispersion of UV light emitted by a pulsed or continuous UV light source. Note that this photometer plate is used to measure the ultraviolet-visible absorption spectrum of the antioxidant with a maximum absorption wavelength of 51 326 \ patent specification (supplement) \ 92 · 05 \ 92104018 200306418 at 27 6 nm. However, the photometer plate can also be used to measure other ultraviolet and visible absorption spectra of other chemical species with different maximum absorption wavelengths in the soldering plating solution by changing the filter used on the UV optical element. For example, a filter that selectively transmits UV light with a wavelength centered at about .403 nm (the maximum absorption wavelength of the tin / brightener complex) can be used, and this photometric Gauges are used for UV-Vis analysis of brighteners. Therefore, the photometer plate of the present invention can be set and configured to measure the ultraviolet-visible absorption spectrum of various components in the sample solder plating solution by simply changing the filter used. This novel photometer plate embeds the equivalent of two complete spectrometers with reference characteristics in addition to the temperature sensing component. Other features of this photometer board include: • 2 signals and 1 reference input on a board with a test point (TP). • Dual LED control using constant current mode (P2) or one LED and -flash (DB9M connector). • Ability to provide sufficient power (12 volts, 1 amp) to the UV flash. • Accepts optically isolated 12 volt or 24 volt (resistor changed to 2K, 1/2 watt) DC trigger. • Adjust the 24 volt input down to the isolated 12 volts (Ml) and 5 volts (M2) on the board. • The spike capture diode (D2 & D3) on the signal input can capture microsecond instantaneous signals. • Optical fiber can make the light source used flexible. 52 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 The photometer board is a printed circuit board containing specific electronic components on it. In addition to its analog-to-digital Unalog-to-digital capabilities ’ADC) and digital-to-analog capabilities’ DAC capabilities, it includes a PIC microprocessor that controls the operation of the sensor. PIC is programmed by a personal computer (PC), which contains the source code for storing and integrating the sensor software. Because PIC is electrically erasable programmable read only memory (EEPROM), it can be programmed by the PC, shut down, and retain stored data. In addition to controlling all aspects of sensor operation, the PIC can be programmed directly from the PC and communicates continuously with the PC via the RS-23 2 protocol. Through the RS-23 2 communication between the PIC microprocessor and the PC, the PC provides a better user interface for the photometer board. In addition, the interface program stored in the PC allows the user to store data from the sensor, set the alarm and the operating data in the sensor, and generate real-time, continuous updates of the sensor data. Table 5 below shows the equipment used at the test points on the photometer boards shown in Figures 25 and 26 and their respective functions. 53 3 26 \ Patent Specification (Supplement) \ 92 · 05 \ 92104018 200306418 Table 5 Test point / pin device function TP1 U1 A Antioxidant peak detection TP2 U2B Reserved as reference TP3 Ml Grounded TP4 Ml 5V TP5 U1 A capacitor Antioxidant signal TP6 U2A is reserved as reference TP7 U1B Brightener signal TP8 U2B Reference peak detection TP9 U 1 2A D / A output of UV-visible voltage signal TP10 U12B Control D / A output of LED TP 1 1 M2 Grounding TP12 M2 Flash 1 2 VDC 1 U6 Chip selection for inputting brightener or antioxidant signal to D / A chip 1 U7 Chip selection for inputting reference to D / A chip 3 U6 Make sure PIC gets from A / Clock of digital data of U6 chip D3 U7 ensures that PIC gets clock of digital data of U7 of A / D chip 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Operation amplifier (see U 1 A of Figure 25) The peak detection and capture technology used can measure fast signals through the following steps: • Xenon flash light burns UV light, and the combined photodiode pair is then passed through the on-board amplifier Light pulses generates a current into a voltage react. \ • The voltage pulse goes down to the photometer board, where it enters the non-inverting terminal of the operational amplifier on line A7 on connector P1. • The inverting terminal of the operational amplifier is matched with the non-inverting terminal and generates a pulse in the feedback circuit including the resistor R5 and the two diodes D2 and D3. | • When the diode allows the charge to pass only in one direction, and charges the 0.11 microfarad capacitor in TP5, the gain in the feedback circuit is 100K / 30K, while preventing the capacitor from discharging . The second diode compensates for the voltage drop (0.7 volts) on the first diode, so that a signal lower than the 0.7 volt turn-on voltage of the diode can be measured. • Store the charge on the capacitor for 11 microseconds, and then the 12-bit Linear Technology LTC 1 29 8 A to D chips (made by Linear Technology Corporate (Milpitas, CA)) convert the voltage into bits. · • After about 75 microseconds, the capacitor is discharged ’and ready to receive the next pulse. The timing of this event sequence is shown in Figures 25-29 below. Note that more than one pulse can be stored on the capacitor at a time, and the R S · 2 3 2 communication on the board fails when the A / D and D / A converter | function to prevent the timing of the device. Fig. 27 shows a pulse generated by a photodiode (for example, an SlC photodiode) in response to a flash of a UV light generated by a flash lamp. This kind of pulse is transformed into the electric charge stored on the capacitor which can be read by a / d device through 55 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418. The graph on the left-hand side depicts the pulses from the photodiode as viewed from the oscillogram of Test Point 1 (TP1) on Figure 25, amplified by the operational amplifier. The figure on the right-hand side depicts three repetitive pulses from the photodiode, each pulse leading to the stored charge on the capacitor as measured at test point 5 (TP5) on Figure 25. Note that the time scales of the left-hand and right-hand diagrams are different. The photodiode pulse is measured in microseconds (A s), which is about 100 microseconds. The stored charge is measured in milliseconds (ms). Approximately 7 5-80 milliseconds. Figure 28 shows the start of the signal program, where a 3.6-volt transistor-transistor logic (TTL) signal from the PIC microcontroller causes the flash to burn UV light pulses, and the end of the signal program, the smaller 2.5 The volt photodiode detector was captured on the capacitor in response to 40 microseconds and read back into the PIC microcontroller by the A / D chip. Figure 29 shows that an analog signal (which is the stored charge on a capacitor caused by a photodiode response) is converted or transferred into a digital format by an A / D device. The transition or transfer begins when the TTL signal (ie, the square wave in Figure 29) occurs, which is approximately 11 microseconds after the peak storage voltage reaches the capacitor. The first 40 microsecond pulse followed by the 20 microsecond inclination angle is actually a 1 ^ 1 ^ 31 · Technology 1 29 8 A / D chip configured as a digital data input in the form of a 3-bit character that can begin to transform. This transition or transfer image is captured by the oscilloscope. Figure 30 shows the entire process including the initial transmission signal, signal detection, conversion from analog to digital format, and output of digital data to the PIC microcontroller, which all occur within 5 to 40 microseconds, which is more like a flash The repetition rate (usually about 10 Hz) determines the short time interval between signals. 56 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Specifically, the last three steps (ie signal detection, conversion, and data output) occur during the period when the voltage charge is stored on the capacitor. Figure 31 shows a typical pulse series measured on a capacitor which is the output of the operational amplifier U 1 A. Within each pulse, the procedure illustrated in Fig. 28 includes charging the capacitor when a UV flash is detected by the photodiode, reading the stored charge, converting the charge data into a digital format, and converting such digital data. Transfer to the PIC microcontroller and discharge the capacitor after reading the data. The pulse frequency is approximately 800 milliseconds or 12.5 Hz. Regarding UV light detectors, the conventional SiC photodiodes generate weak current signals that are susceptible to environmental noise, and a significant portion of the signal is lost due to a low signal-to-noise ratio. In order to solve the problem of the conventional S i C photodiode, the present invention uses a split photodiode or a photodiode provided with an integral operation amplifier to minimize signal interference. The split photodiode, such as the UV-enhanced silicon photodiode in the standard T05 package, has a very strong signal before any amplification and a stable pulse peak height that produces less variation. Figure 32 shows the original signal from a UV-enhanced silicon photodiode as described above in a sample vessel containing only air and measured with an oscilloscope. The magnitude of the original signal was greater than 1.7 volts without any amplification, and the FWHM was approximately 120 microseconds. This signal is significantly better than that measured with a conventional SiC photodiode (which cannot be measured without at least one stage of amplification of a photometer plate). The strong signal seen above shows that the signal-to-noise ratio will no longer be a problem. Optical unit for performing spectroscopy 57 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Another aspect of this application relates to a target component, such as a brightener, contained in a solution for conducting sample welding. Or an optical unit for the spectral analysis of antioxidants. Such an optical unit may include: a first fluid chamber of a first capacity; one or more fluid inlets connected to the first fluid chamber for introducing one or more test solutions; a second volume of the first fluid chamber connected A second fluid chamber, wherein the second volume is smaller than the first volume; a fluid outlet connected to the second fluid chamber for discharging one or more test solutions; and if necessary, in the first and / or second fluid chamber A fluid mixing device for mixing one or more test solutions; an irradiation light source for irradiating light into the second fluid chamber; for detecting transmission or transmission by one or more test solutions in the second fluid chamber A photodetector connected to the illuminating light source of the emitted light; and a computing device connected to the photodetector for collecting an absorption spectrum of the one or more test solutions as needed and performing a spectral analysis based thereon. FIG. 33 shows an external view of an optical unit according to a specific example of the present invention, which has two light source frames, two detection frame covers, a stirring motor combination, and eight fluid ports for introducing a test solution. Figure 3 A shows the upper half of the optical unit, which includes a cover and a mixing shaft for mixing the test solution. 33B and 33C show cross-sectional views of the bottom half of the optical unit, including 58 326 \ Patent Specification (Supplement) \ 92-05 \ 921〇4〇18 200306418 including a large fluid chamber and a small fluid connected to it room. A small fluid chamber preferably has a capacity of about 1/5 to about 1/2 of a large fluid chamber. The light source and light detector are arranged and configured to provide one or more light paths through the small fluid chamber for spectral analysis. The fluid port is connected to the large fluid chamber to introduce one or more test solutions, and the mixing shaft extends through the entire large fluid chamber to the small fluid chamber and terminates above the optical path. Therefore, the large fluid chamber provides enough space for fluid introduction and mixing without obstructing the light path or otherwise interfering with the spectral analysis in the small fluid chamber. This dual-chamber configuration of the optical unit requires the minimum amount of sample solder plating solution to be used for analysis, which is determined by the capacity of the small fluid chamber, not the capacity of the large fluid chamber. Since the antioxidant component of the solder plating solution is light sensitive, the present invention provides an opaque polymeric cover to cover both the large and small fluid chambers. Such an opaque polymeric cover is preferably a black polyvinyl chloride cover. In addition, since the solder plating solution is highly corrosive, it is preferred that the optical unit of the present invention include a resistive lining on the inner surfaces of the large and small fluid chambers. This type of uranium-resistant lining is better with Teflon lining, and Teflon® lining is the best. Figure 34 shows a perspective view of an optical unit of the present invention in which a light source directs a light guide through a small fluid chamber to a light detector for spectral analysis. A computing device (not shown here) may be provided, which is connected to the photodetector 'to collect the absorption spectra of the one or more test solutions and perform spectral analysis based on their absorption spectra. The computing device may include a personal computer, a workstation, a microprocessor, an on-line analyzer, or any other suitable computing device. Raman spectroscopy Raman spectroscopy is a non-destructive quantitative and qualitative tool for identifying and analyzing both inorganic and organic species. 59 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 It is widely regarded as a complementary analytical method for infrared spectroscopy. A significant advantage of Raman spectroscopy over infrared spectroscopy is that it can use sample vessels made of glass or quartz to collect useful molecular information under aqueous conditions. The equipment of Raman spectroscopy includes three main components: a high-intensity light source, a sample illumination system, and a spectrophotometer. The range of light sources used in Raman spectroscopy ranges from HeNe lasers to N d: Y A G lasers. The choice of laser for analysis is largely determined by the analytical method and molecular species. Sample lighting can be achieved using many techniques. With the development of fiber optic technology, great variability in cell design can be achieved. The Raman spectroscopy system can be incorporated into an analysis unit designed for the analysis of plating solutions, which allows continuous flow of the sample plating solution and provides instant in-situ analysis of the sample solution (i n s i t u a n a 1 y s i s). The analysis unit also includes inlet and outlet valves to isolate such units from sample flow during calibration or cleaning procedures. Raman spectroscopy can be used because the Raman spectrophotometer detects the amount of radiant energy scattered by a specific component of the plating solution, and because the intensity of this scattered radiant energy is linearly proportional to the concentration of the specific component Accurately and accurately determine the concentration of various components in the plating solution, including inorganic or organic components. In general, Raman spectroscopy provides an efficient concentration method for solder plating solutions, or other types of metal plating solutions. In addition, the recently available spectral database makes it possible to use the measured spectral data for spectral research. 60 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Therefore, it is possible to separate many components of the sample solution. Spectroscopy, and impurities or by-products in such sample solutions can be easily determined. Although the present invention has been disclosed in various ways with reference to illustrative specific examples and features, it should be clear that the specific examples and features described above are not intended to limit the scope of the present invention, and those skilled in the art can easily think of other Changes, modifications and other specific examples. Therefore, the present invention should be interpreted broadly in accordance with the scope of the patent application described later. [Schematic description] Figure 1 is a graph showing the potential response of the solution before and after adding the sample methanesulfonic acid solution and the potential response of the solution before and after adding the calibration methanesulfonic acid solution according to its six measurements. Figure 2 is a titration curve of MSA measured during a titration using 0.1 M KOH as a titrant, and plotted as a function of the pH or percent recovery of methanesulfonic acid (MS A) as the added volume of KO Titrant. Figure 3 is a graph plotting the potential of a sample solder plating solution as a function of the volume of iodine titrant added to such a sample solution according to the iodine titration method of tin analysis. 4A and 4B show a dual platinum electrode for measuring the redox potential of a sample solder plating solution according to a specific example of the present application. Figure 5 is a titration curve for iodine titration of tin ions using a dual platinum polarized electrode. Figure 6 is a comparison of the iodine titration curve of tin with lead ions removed from the sample solution using HC1 prior to the titration procedure, and the iodine titration curve of lead ions stabilized with EDTA. 61 326 \ Patent Specification (Supplement) \ 92-05 \ 921〇4〇18 200306418 Figure 7 is another tin-iodine titration curve, in which KC1 was used to remove lead ions from the sample solution before the titration procedure. Figure 8 shows the results of a series of 24 iodine titrations of a series of tin analysis performed with pre-titration of mis-ions. Figure 9 shows a linear plot of the four iodine titration results for a tin analysis connected to a pre-titration with lead ions. Figure 10 shows the relationship between the pH 値 of the sample soldering solution and the EDTA and the second titration solution containing 0Η · added during the parallel titration of lead and / or total metal analysis. Figure 11 shows a number of titration curves for a sample plating solution based on a parallel titration method for lead and / or total metal analysis, which is a function of the pH of the sample plating solution to the added volume of EDA. Fig. 12 shows a plurality of titration curves in which the added volume of NaOH (ie, the second titration solution) is plotted as a function of the added EDTA during the parallel titration process of Fig. 11. Figure 13 shows the UV-visible absorption spectrum measured for various test solutions including: (1) a solution containing methanesulfonic acid (MSA) and a brightener; (2) a solution containing MSA, a brightener and tin ions Solution; (3) a solution containing MSA, a brightener, tin ions, and lead ions; (4) a solution containing MSA, a brightener, tin ions, lead ions, and antioxidants; and (5) a solution containing MSA, brighteners Solutions of oxidants, tin ions, lead ions, antioxidants and polymeric nonionic surfactants. Figure 14 shows three individual calibration curves made using fresh standard brightener solutions based on the UV-Vis spectroscopy method for brightener analysis. Figure 15 shows the increase in brightener caused by the addition of various standards of brighteners. 62 326 \ Patent Specification (Supplements) \ 92-05 \ 92104018 200306418 The concentration of the brightener is obtained after each addition of the standard Linear calibration curve plotted as a linear function of the absorbance measured by the nominal soldering solution. Figure 16 shows the initial measurement results using a fresh standard brightener solution based on the UV-Vis spectroscopy method of brightener analysis, followed by the same brightener standard solution, but leaving these standard solutions to rest Comparison of measurement results obtained after a specific period up to three days. Figure 17 shows various UV-visible absorption calibration curves made by using standard brightener solutions with the same concentration but different aging. Fig. 18 is a graph plotting the oxidation-reduction potential of a sample solder plating solution as a function of the pH 値 of such a sample solution in an antioxidant analysis. Figure 19 shows the three redox potential response curves for the analysis of antioxidants, each plotting the redox potential of a calibrated solder plating solution of known antioxidant concentration as a function of the pH 値 of this calibration solution. Fig. 20 shows various UV-visible absorption calibration curves measured using an antioxidant solution or an antioxidant extracted from a sample solder plating solution and an antioxidant-iron complex. Figure 21 shows the ultraviolet-visible absorption spectrum of an antioxidant-molybdenum complex formed by adding a pure antioxidant to a complex solution containing molybdenum dioxide, ammonium acetate and EDTA. Figure 22 shows an antioxidant analysis. The measured absorbance response for the MoO2C12 / NH4C2H302 / EDTA complex solution is a function of the volume of pure antioxidant added to the complex solution. Figure 23 shows a calibration curve quantified as a relationship between the antioxidant concentration and the measured absorbance. 63 3 of 6 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418 Figure 24 plots the UV light transmittance of an unused filter as a function of the wavelength of UV light transmitted by this filter and Comparison of the transmittance and transmission wavelength of the filter after 3 months of use. Figures 25 and 26 show photometer plates specially designed for UV-visible spectrum measurement at short wavelengths of about 276 nm. Figure 27-31 shows the detection during each step of the UV light detection process including the burning of a UV flash, the capacitor is charged by a photodiode, the stored charge is converted or converted into a digital signal, and the digital signal is output to a personal computer. Get the signal. Figure 32 shows the original signal output by the UV-enhanced silicon split photodiode. 33 and 33A-33C show various drawings of an optical unit according to a specific example of the present invention. Fig. 34 shows a schematic diagram of the optical unit of Figs. 33-33C. 64 326 \ Patent Specification (Supplement) \ 92-〇5 \ 92104018

Claims (1)

200306418 Scope of patent application 1.  A method for determining the acid concentration contained in a sample solder plating solution, including the following steps: (a) measuring the potential response of one or more calibration solutions of known acid concentration; (b) determining the acid concentration in the solution based on the calibration measurement Correlation with potential response; (c) measuring the potential response of the sample solder plating solution; and (d) based on the correlation between the potential response measured in step (c) and the measurement of frustration in step (b) The acid concentration in the fresh mineral solution of the sample was measured. 2. The method of claim 1 in which the acid contained in the sample plating solution includes methanesulfonic acid. 3. The method according to item 1 of the scope of patent application, wherein the sample solder plating solution is diluted before the measurement of the potential response is performed. 4. The method of claim 3, wherein the sample solder plating solution is diluted by adding the sample solder plating solution to deionized water. 5. The method of claim 3, wherein the sample solder plating solution is diluted by adding the sample solder plating solution to a solution containing deionized water and potassium nitrate. 6. The method of claim 5, wherein the solution comprises potassium nitrate in a concentration ranging from about 15% to about 25% of the total volume of the solution. 7. The method of claim 3 in the patent application range, wherein the sample solder plating solution is diluted at a dilution ratio ranging from about 10 to about 100. 8. The method according to item 3 of the scope of patent application, wherein the sample plating solution is diluted at a dilution ratio of about 50. 65 Patent Specification (Supplement) \ 92-〇5 \ 92104018 200306418 9. For example, the method of claim 3, wherein the sample solder plating solution is diluted to reach pH 値 in the range of from about 3 to about 3. 1 0. For example, the method of claim 3 in the patent application range, wherein the sample solder plating solution is diluted so as to reach a pH in the range of about 2. 1 1. For example, the method of claiming the scope of patent application, wherein: step (a) includes measuring the potential response of two consecutive standard acid additions in a calibration solution, the acid concentrations and volumes of the two standard acid additions are equal to each other and are known, (B) Including the slope 1 indicating the correlation between the acid concentration of the solution and the potential response according to the following equation: En-Ei k = --- log 2 where [and five " The potential response of the calibration solution measured after the calibration solution, step (c) includes measuring the potential response of the sample solder plating solution before and after adding a third standard acid with a known acid concentration and volume, and step (d ) Includes calculating the acid concentration in the sample solder plating solution according to the following equation: where the acid concentration in the sample solder plating solution has been used, h is the volume of the third standard acid addition, ~ is the third standard acid addition The acid concentration in the sample, K is the volume of the sample plating solution, and A and & are respectively before and after the third 66 patent specification (Supplement) \ 92-05 \ 92104018 200306418 standard acid addition The potential response of the sample solder plating solution. 12 The method according to item 11 of the patent application scope, wherein the calibration solution includes deionized water. 1 3. The method of claim 12 in the patent application range, wherein the calibration solution further includes potassium nitrate having a concentration in a range from about 15% to about 25% of the total volume of the solution. 1 4. For example, the method according to item 11 of the patent application scope, wherein the acid concentration in the sample solder plating solution is estimated before the third standard acid addition, and the third standard acid addition is performed to make the sample solder plating solution The estimated acid concentration is approximately doubled. 1 5. For example, the method according to item 11 of the patent application range, wherein the sample solder plating solution is diluted before measuring the potential response and the third standard acid addition. 1 6. For example, the method according to item 13 of the patent application range, wherein the sample plating solution is diluted at a dilution ratio ranging from about 10 to about 1000. 17 · The method according to item 11 of the patent application range, wherein the acid concentration calculated for the sample solder plating solution is characterized by a relative standard deviation of less than about ± 5%. 1 8. For example, the method of claim π, wherein the acid concentration calculated for the sample solder plating solution is characterized by less than about ± 1.  Relative standard deviation of 5%. 19 · The method according to item 1 of the patent application scope, wherein: step (a) includes measuring the potential increase caused by adding one or more calibration solutions of known acid concentration to an alkaline solution, and step (b) Including determining the correlation between the acid concentration in the calibration solution and the potential increase caused by adding the calibration solution, 67 326 \ Patent Specification (Supplement) \ 92-05 \ 92104018 200306418, step (C) includes measuring the The potential increase caused by the addition of the sample solder plating solution to the alkali solution, and step (d) includes determining the sample based on the increase in potential measured in step (C) and the correlation measured in step (b). Acid concentration in the plating solution. 20. The method according to item 19 of the scope of patent application, wherein the measurement of the potential increase in steps (a) and (c) includes the following steps: (i) measuring two immersed in an alkaline solution under a predetermined current The potential between the electrodes; (i 1) the calibration solution or the sample welding solution D into the alkaline solution; (1 ii) then measure the potential between the electrodes in the alkaline solution at the predetermined current ; And Uv) determined by adding the calibration solution or the sample solder plating solution to the alkaline solution by subtracting the potential measured in step (1) ′ from the potential measured in step (n). The potential increases. twenty one . For example, the method of claim 20 in the patent application range, wherein in step (i), the potential is continuously monitored for a sufficient time to make the two electrodes reach an equilibrium state. 2 2 · The method according to item 21 of the scope of patent application, wherein in step (1), the potential is continuously monitored for a time from about 20 to about 40 seconds. twenty three . The method of claim 20, wherein the acid concentration calculated for the sample solder plating solution is characterized by a relative standard deviation of less than about ± 5%. 24. The method of claim 20, wherein the acid concentration calculated for the sample solder plating solution is characterized by a relative standard deviation of about ± 1%. 68 326 \ Patent Specification (Supplement) \ 92 · 〇5 \ 921040] 8 200306418 2 5.  A method for determining the acid concentration contained in a sample solder plating solution, including the following steps: (a) providing a sample solder ore solution having an unknown acid concentration; (b) titrating the sample solder plating solution with an alkali titrant ; (C) monitor the pH of the sample welding solution during the titration process, and terminate the titration procedure when a predetermined end point is reached, where the pH of the sample welding solution at the predetermined end point is from about 3. 5 to 4. Within the range of 5; (d) record the total amount of the alkali titrant used to reach the predetermined end point; (e) determine the titrant that reacts with the tin ions in the sample solder plating solution to form an insoluble tin compound if necessary Calculate the acid concentration in the sample plating solution based on the total amount of titrant used, and if necessary based on the amount of titrant that reacts with the tin ions therein. 2 6. For example, the method of claim 25 in the patent scope, wherein the pH of the sample plating solution at the predetermined end point is from about 3.  8 to about 4. Within the range of 4. 27. The method according to item 25 of the scope of patent application, wherein the pH of the sample plating solution at the predetermined end point is about 4. 28. The method of claim 25, wherein the titrant comprises a group selected from the group consisting of at least one compound of sodium hydroxide, potassium hydroxide, and ethanolamine. 29. The method according to item 25 of the patent application scope, wherein more than 90% of the acid contained in the sample solder plating solution is recovered by the alkali titrant at the predetermined end point. 0 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 040] 8 69 200306418 3 0. For example, the method of claim 25 in the patent application range, wherein more than 99% of the acid contained in the sample solder plating solution is recovered by the alkali titrant at the predetermined end point. 3 1-a method for determining the tin concentration in a sample solder plating solution containing tin and lead ions, comprising titrating the sample solder plating solution with a titration solution containing one of materials selected from the group consisting of iodine and iodide, and The reduction oxidation potential response of the sample solder plating solution was measured during the titration. 32. The method of claim 31, wherein the titration solution contains iodine. 3 3 · The method according to item 32 of the scope of patent application, including the following steps: U) adding a stabilizing solution to the sample solder plating solution to stabilize the lead ions therein, and prevent the lead ions in the subsequent Precipitation during the titration; (b) titrating the sample solder plating solution with a titration solution containing iodine; (c) monitoring the redox potential of the sample solder plating solution during the iodine titration process to determine the end point of the titration; and (d ) Calculate the tin concentration in the sample plating solution based on the titration endpoint measured in step (c). 34. The method of claim 33, wherein the stabilizing solution comprises ethylenediamine tetraacetate (EDTA). 35. The method of claim 34, wherein the stabilizing solution further comprises ammonium acetate in an amount sufficient to adjust the pH of the sample solder plating solution to higher than about 4. 3 6 · The method according to item 33 of the scope of patent application, wherein the sample is welded and plated 70 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 040] 8 200306418 The liquid is diluted before adding the stabilization solution . 3 7. For example, the method according to item 36 of the patent application scope, wherein the sample plating solution is diluted at least 10 times. 3 8. For example, the method according to item 36 of the patent application scope, wherein the sample plating solution is diluted at least 50 times. 3 9. For example, the method according to item 36 of the patent application range, wherein the sample plating solution is diluted at least 100 times. 4 〇. For example, the method according to item 33 of the patent application scope, wherein a redox potential electrode is used to monitor the redox potential of the sample solder plating solution. 4 1. For example, the method of claim 40, wherein the redox potential electrode comprises a dual-polarized europium electrode. 4 2. For example, the method of claim 32 of the patent scope includes the following steps: (a) adding a lead precipitant to the sample solder plating solution to remove the lead ion from the sample solder plating solution; (b) using Titrate the sample solder plating solution with a titration solution containing iodine; (c) monitor the redox potential of the sample solder plating solution during the iodine titration process to determine the end point of the titration; and (d) based on the measurement in step (c) The titration end point calculates the tin concentration in the sample solder plating solution. 43. The method according to item 42 of the patent application, wherein the sample solder plating solution is diluted before the lead precipitant is added. 4 4. For example, the method of claim 42 in which the lead precipitant contains at least one compound selected from the group consisting of HC1, NaCl, and KC1. 4 5 · The method according to item 42 of the scope of patent application, wherein the lead precipitant package 326 \ Patent Specification (Supplement) \ 92-05 \ 921 〇4〇 18 200306418 contains HC1. 4 6. For example, the method according to item 42 of the patent application range, wherein the lead precipitant contains H C1 ~ Chen 'solution with H C1 ~ Chen degree from about 20% to about 45% by weight. 4 7. The method according to item 42 of the patent application, wherein the lead precipitant comprises an H C1 solution having an H C1 concentration of from about 35 to about 40% by weight. 4 8. For example, the method according to item 42 of the patent application range, wherein the source agent contains a KC1 solution having a KC1 concentration in a range from about 1M to about 3M. 4 9. For example, the method according to item 42 of the patent application range, wherein the sinking agent contains a K C 1 solution having a K C 1 concentration of about 2 M. 5 0. A method according to item 42 of the patent application, wherein the lead precipitant comprises a Na C1 solution having a Na C1 concentration in a range from about 1 M to about 3 M. 5 1. The method of claim 42 in which the lead precipitant comprises a NaCl solution having a NaCl concentration of about 2M. 5 2. For example, the method of claim 42 in which the redox potential of the sample solder plating solution is monitored using a redox potential electrode. 5 3.  -A method for determining the lead concentration in a sample solder plating solution containing tin and lead ions, including the following steps: (a) measuring the total metal concentration in the sample solder plating solution; Method to determine the tin concentration in the sample solder plating solution; (c) Calculate the lead concentration in the sample solder plating solution by subtracting the tin concentration from the total metal concentration. 5 4. For example, the method of claim 53 in the patent scope, wherein the total metal concentration in the sample welding solution is determined by a titration method including the following steps: 326 \ Patent Specification (Supplement) \ 92-05 \ 921 〇4〇] 8 72 200306418 (a) Add an excess of a complexing agent to the sample solder plating solution so that metal ions in the sample solution and the complexing agent form a complex; (b) Titrate the sample solution with a titration solution And the excess of the complexing agent that is not mismatched with the metal ions in the sample plating solution is consumed; (c) monitoring the titration program to determine a titration endpoint, where the amount of titration solution used to reach the titration endpoint is recorded; And (d) calculating the total metal concentration in the sample solder plating solution based on the amount of the complexing agent added to the sample solution and the amount of the titration solution used to consume the excess of the complexing agent. 5 5. For example, the method according to item 54 of the patent application range, wherein the sample solder plating solution is diluted before adding the complexing agent. 5 6. For example, the method of claim 54, wherein the complexing agent comprises ethylenediamine tetraacetate (EDTA). 5 7. For example, the method according to item 56 of the patent application scope, wherein ammonium acetate is used in combination with the complexing agent to adjust the pH of the sample solder plating solution to be higher than about 4. 5 8. For example, the method according to item 56 of the patent application range, wherein the titration solution contains copper sulfate to consume excess EDTA that is not mismatched with metal ions in the sample plating solution. 5 9. For example, the method according to item 58 of the patent application scope, wherein the titration is monitored by using a group selected from the group consisting of an ion selective electrode of a cadmium ion selective electrode and a calcium ion selective electrode. 73 3m Patent Specification (Supplement) \ 92-05 \ 921 (MO 18 200306418 60 — A method for determining the lead concentration in a sample solder plating solution, including the following steps: (a) measuring one or more known lead concentrations Potential response of the calibration solution; (b) Determining the correlation between the lead concentration of the solution and the potential response based on a calibration measurement; (c) Measuring the potential response of a sample solder plating solution; and (d) Based on step (c) The measured potential response and the correlation measured in step (b) are used to determine the lead concentration in the sample solder plating solution. 6 1 · The method according to item 60 of the patent application scope, wherein a lead ion selective electrode is used Measure this potential response. 62. For example, the method of claim 60 of the patent application scope, wherein the sample solder plating solution is diluted before the measurement of the potential response is performed. 6 3. For example, the method of claim 60 of the patent application range, wherein the sample solder plating solution is diluted at a dilution ratio ranging from about 50 to about 200. 64. The method according to item 60 of the patent application range, wherein the sample solder plating solution is diluted at a dilution ratio of about 100. 6 5. For example, the method of claim 60 of the patent application range, wherein the sample plating solution is diluted to reach a pH higher than 3. 6 6. For example, the method of claim 60, wherein the sample solder plating solution is diluted to a pH value in a range from about 3 to about 5. 67. For example, the method of claim 60, wherein the sample plating solution is diluted with a concentrated electrolyte solution. 6 8 · The method according to item 60 of the scope of patent application, wherein: Step (a) includes measuring 326 \ Patent Specification (Supplement) \ 92-05 \ 92], which is the addition of two consecutive standard errors in a calibration solution. 〇] 8 74 200306418 Potential response. The lead concentrations and volumes of the two standard lead additions are equal to each other and known. Step (b) includes calculating the slope of the correlation between the lead concentration of the solution and the potential response according to the following equation. : Eil — E i k — — — log 2 where 仏 and 系 are the potential response of the calibration solution measured after each standard lead is added to the calibration solution, step (c) includes adding lead concentration Before and after the third standard lead addition with a known volume, measure the potential response of the sample solder plating solution, and step (d) includes calculating the lead concentration in the sample solder plating solution according to the following equation: Va C a Cl: ~~ -------------------------- Vs [anti \ 〇g {(Ei-E \) / k)-l] where G is the sample The lead concentration in the plating solution is the volume of the third standard lead addition, and the α is the lead concentration in the third standard lead addition. Volume, ^ based solder plating solution of the sample, and Fo ^ and in the third sub-lines were added to the lead standard sample before and after the solder plating solution of the potential response. 6 9. For example, the method according to item 68 of the patent application scope, wherein the potential response is measured using a lead ion selective electrode. 7 0. For example, the method of claim 68, wherein the sample solder plating solution is diluted before the third standard lead addition. 7 1. For example, the method of applying scope 70 of the patent scope, wherein the calibration solution package 75 326 \ Patent Specification (Supplement) \ 92 · 05 \ 92104018 200306418 contains deionized water. 7 2. For example, the method of claim 68 in the patent application scope, wherein the lead concentration in the sample solder plating solution is estimated before the third standard lead addition, and the third standard lead addition is performed to make the sample solder plating solution The estimated lead concentration is approximately doubled. 7 3.  —A method for determining the lead concentration in a sample solder plating solution, including the following steps: (a) adjusting the pH of the sample solder ore solution to from about 4 to about 4. (B) Titrate the sample solder plating solution by adding a continuous amount of a main titration solution containing EDTA; (c) At the same time as step (b), monitor the amount of After the main titration solution, the pH of the sample solder plating solution was 値, and when a decrease in pH was observed in the sample solder plating solution, a sufficient amount of a second titration solution was added to the sample solution to add the next The pH of the sample solution was adjusted back to the base value before measuring the main titration solution; (d) The titration was terminated at an end point when the addition of the main titration solution could no longer cause the pH of the sample solder plating solution to drop. Procedures; (e) record the total volume of the second titration solution used, and if necessary the total volume of the main titration solution that reached the end of the titration; and (0 based on the total volume of the second titration solution used , Determine the lead concentration in the sample solder plating solution; (g) if necessary, based on the total volume of the main titration solution that reached the end of the titration, determine the total metal concentration in the sample solder plating solution. 76 326 \ Patent Specification (Supplement Pieces) \ 92-05 \ 92104018 200306418 7 4. For example, the method of claim 73, wherein the second titration solution contains a strong base. 75. The method of claim 73, wherein the second titration solution comprises at least one compound selected from the group consisting of metal hydroxides. 7 6. For example, the method of claim 73, wherein the second titration solution comprises at least one compound selected from the group consisting of sodium hydroxide and potassium hydroxide. 7 7 · The method according to item 73 of the scope of patent application, wherein the pH of the sample solder plating solution is monitored using a pH probe. 78. The method according to item 73 of the scope of patent application, wherein in step (a), the pH of the sample plating solution is adjusted by using an alkaline solution. 7 9. The method of claim 78, wherein the alkaline solution contains hydroxide ions. 80. The method according to item 73 of the scope of patent application, wherein the total volume of the main titration solution used before any pH drop is observed in the sample solder plating solution is measured to determine the tin in the sample solder plating solution. concentration. 8 1 — A potential self-adjusting (Potentic) Statlc method for measuring the concentration of polymerized nonionic surfactants in a sample solder plating solution by measuring the following parameters: (a) An infinite increase in plating current occurs The time required; or (b) during the infinite increase of the plating current, an analytical signal selected from the group consisting of a ore current and a stripping charge is measured. 8 2 · The method according to item 81 of the scope of patent application, wherein during the process of the electroplating 77 326 \ Patent Specification (Supplement) \ 92-05 \ 9210 8 200306418 the infinite increase of current, the measurement is selected from the group including electroplating The analysis signal of the group consisting of the current and the stripped charge is used to determine the concentration of the polymerized nonionic surfactant in the sample solder plating solution. 8 3. For example, the method according to item 82 of the patent application scope, wherein a linear potential scanning analysis is performed to measure the analysis signal during the infinite increase of the plating current. 84. The method according to item 82 of the scope of patent application, wherein a potential step electroplating-stripping analysis is performed to measure the analysis signal during the infinite increase of the plating current. 8 5. For example, the method of claim 82 in the scope of patent application, wherein the stripped charge is measured during the process of the infinite increase of the plating current. 8 6 · The method according to item 81 of the scope of patent application, wherein the sample solder plating solution is diluted before measurement. 8 7 · — A potentiometric titration method for determining the concentration of polymerized nonionic surfactants in a sample solder plating solution, including the following steps: (a) Adding a titration solution to the lead-polymerized non- The ionic surfactant complex forms an insoluble reaction product and titrates the sample plating solution; (b) Detects a titration end point of the sample titration procedure in step (a), and records the end point used to reach the titration end point. The amount of titration solution; (c) providing a plurality of standard solder plating solutions containing a polymeric nonionic surfactant at a unique known concentration; (d) titrating the plurality of standard solder plating solutions by using the titration solution, And detect the titration end point of each of the plurality of standard soldering plating solutions; 78 326 \ Patent Specification (Supplements) \ 92 · 〇5 \ 92】 040] 8 200306418 (e) Calculate the volume of use of the titration solution An experimental titration factor associated with the concentration of the polymerized non-ionic surfactant in the plurality of standard solder plating solutions; and (f) based on the volume of the titration solution recorded in step (b) and in step (e) in The calculated factor of titration experiment, measurement of the sample of liquid solder polymerizable nonionic surfactant concentration of the plating solution. 8 8. For example, the method of claim 87, wherein the titration solution contains sodium tetraphenylborate. 8 9. For example, the method according to item 88 of the patent application range, wherein the titration end point is detected by a surfactant electrode. 9 0.  A method for determining the concentration of a brightener in a sample solder plating solution, including measuring an ultraviolet-visible absorption spectrum of one of the sample solder plating solutions, and determining whether the sample solder plating solution ranges from about 393 nanometers (nm) to The absorbance at one wavelength in the range of about 413 nanometers, and the concentration of the brightener in the sample solder plating solution is calculated based on the absorbance at the wavelength. 91. The method of claim 90, wherein the absorbance of the sample solder plating solution is measured at a wavelength ranging from about 398 nm to about 408 nm. 9 2 · The method according to item 90 of the scope of patent application, wherein the absorbance of the sample solder plating solution is measured at a wavelength of about 4 10 nm. 9 3. For example, the method of claim 90, wherein the sample solder plating solution is diluted before measurement. 94. The method of claim 93, wherein the sample plating solution is diluted by about 10 to about 1000 times with deionized water. 79 326 \ Patent Specification (Supplement) \ 92-05 \ 921040] 8 200306418 9 5. For example, the method of applying for item 90 of the patent scope includes the following steps: (a) measuring and recording the absorbance of the sample welding ore solution; (b) adding a plurality of known standards of brighteners to the sample welding In the plating solution; (c) After each standard addition of the brighteners, measure the absorbance of the sample solder plating solution; (d) Determine the sample solder plating caused by the standard additions of the brighteners The increase in the concentration of the brighteners in the solution; (e) the increase in the concentration of the brighteners in the sample solder plating solution to be measured in step (d) as the measurement in step (c) Plot a function of the absorbance of the sample solder plating solution to make a calibration curve; and (f) extrapolate the calibration curve to measure one of the calibration curve's y-intercepts, where The absolute value of the y-intercept is recorded as the concentration of the brighteners in the sample soldering solution before any standard additions were introduced. 96.  For example, the method of applying for item 95 of the patent scope, wherein the standard addition of the brightener includes a freshly prepared brightener solution. 97.  For example, the method of claim 95, wherein the standard addition of the brightener is filtered to remove particles from the brightener before the brightener is added to the sample solder plating solution. 9 8.  —A method for determining the concentration of antioxidants in a sample solder plating solution, including the following steps: (a) adding an acid solution to the sample solder plating solution to the sample 80 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 040] 8 200306418 The pH of the solder plating solution was raised to a predetermined value; (b) Before the acid solution was added, the redox potential of the sample solder plating solution was monitored; (c) by The redox potential measured by the sample solder plating solution is plotted as a function of pH 値 to produce a redox potential response curve, and (d) determined by analyzing the redox potential response curve of the sample solder plating solution. Antioxidant concentration in this sample soldering solution ° 9 9. For example, the method of claim 98, wherein the sample is analyzed by comparing the slope of the redox potential response curve with the slope of the redox potential response curve made from a calibrated solder plating solution of known antioxidant concentration. The redox potential response curve of the plating solution. 1 0 0. For example, the method of claim 98, wherein the added acid solution includes methanesulfonic acid. 1 0 1. For example, the method of claim 98, wherein the sample plating solution is diluted to a pH of about 0.1 to about 0.1. 5 to about 1. Within the range of 5. 102.  For example, the method of claim 98, wherein the sample plating solution is diluted to a pH of about 1. 103.  For example, the method of claim 98, wherein a redox potential electrode is used to measure the redox potential of the sample plating solution. 1 04 · —A method for determining the concentration of an antioxidant in a sample solder plating solution 'includes forming a derivative of the antioxidant that can be detected by ultraviolet and visible spectroscopy, and making the derivative of the antioxidant An ultraviolet-visible absorption analysis is performed at a wavelength where the UV absorbance is maximized to determine the sample welding step 81 326 \ Patent Description Supplement) \ 92-05 \ 92] 040] 8 200306418 The antioxidant concentration in the plating solution . 1 05. The method of claim 104, wherein the derivative of the antioxidant is formed by adding the sample solder plating solution to a complex solution containing at least one iron compound, and wherein the ultraviolet -Visible absorption analysis was performed at a wavelength of about 750 nm. 106. The method of claim 104, wherein the complex solution comprises ferric chloride. 1 07. The method of claim 105, wherein the complex solution further comprises pyridine and methanol. 10 8. For example, the method of claim 104, wherein the antioxidant is extracted from the sample solder plating solution before forming the derivative of the antioxidant and the ultraviolet-visible absorption analysis. 109. The method of claim 108, wherein the antioxidant is extracted from the sample solder plating solution by using an ethyl acetate solution. 1 1 0. The method of claim 104, wherein the derivative of the antioxidant is formed by adding the sample solder plating solution to a complex solution containing at least one molybdenum compound, and wherein the ultraviolet-visible absorption The analysis was performed at a wavelength in the range from about 2 80 nm to about 3 20 nm. 1 1 1 The method according to item Π 0 of the patent application range, wherein the ultraviolet-visible absorption analysis is performed at a wavelength of about 300 nm. 1 1 2. For example, the method of claim 110 in the patent application range, wherein the complex solution comprises molybdenum dichloride. 1 1 3. For example, the method of claim 112 in the patent application range, wherein the complex solution further includes ammonium acetate and EDTA. 82 326 \ Patent Specification (Supplement) \ 92-05 \ 92] 04018 200306418 1 1 4. For example, the method according to item 113 of the patent application range, wherein the complex solution further comprises ethanolamine. 1 1 5.  —A method for determining the antioxidant concentration in a sample solder plating solution 'includes directly performing an ultraviolet-visible absorption analysis of the solder plating solution at a wavelength that maximizes the UV absorbance of the antioxidant, and determining based on the results of the ultraviolet-visible absorption analysis A step of concentration of antioxidant in the sample solder plating solution. 1 1 6. For example, the method of claim 115 in the patent application range, wherein the UV-visible absorption analysis of the solder plating solution is performed at a wavelength in a range from about 256 nm to about 296 nm. 1 1 7. For example, the method of item 115 of the patent application range, wherein the UV-visible absorption analysis of the soldering plating solution is performed at a wavelength in a range from about 270 nm to about 282 nm. 1 1 8. For example, the method according to item 115 of the patent application range, wherein the ultraviolet-visible absorption analysis of the solder plating solution is performed at a wavelength of about 276 nm. 1 1 9. For example, the method of applying item 116 of the patent scope, wherein a UV flash lamp is used to generate UV light having a wavelength in a range from about 160 nm to about 5000 nm at an emission frequency of at least 25 Hertz (Hz) 'And wherein the UV flash has a power consumption rate of not more than 2 watts. 1 2 0. For example, the method of claim No. 119 in the patent application range, wherein a filter is used so that UV light having a wavelength in a range from about 256 nm to about 296 nm is at least 20%. The transmittance is selectively passed. 1 2 1. The method of claim 120, wherein the filter selectively passes UV light having a wavelength in a range from about 270 nm to about 282 nm. 83 3: 26 \ Patent Specification (Supplement) \ 92-05 \ 92] 〇4〇] 8 200306418 1 2 2. For example, the method of claim 120 in the scope of patent application, wherein a low hydroxyl fiber is used to transmit selected UV light from the filter to an optical unit containing the sample soldering solution. 1 2 3. For example, the method of claim No. 122 in the scope of patent application, wherein a split photodiode is used to detect the UV light transmitted by the sample solder plating solution and generate a current. 1 2 4 · The method of item No. 123 of the scope of patent application, wherein a capacitor stores electric charge in response to the current generated by the split photodiode. 1 2 5. For example, the method according to item 123 of the patent application range, wherein the current generated by the combined photodiode is amplified by the on-board operation amplifier. 12 6. For example, the method of applying for the scope of the patent No. 124, wherein the A / D device is used to read the charge stored in the capacitor and convert it into a digital signal, and wherein the A / D device outputs the digital signal to a PIC microcomputer. Controller. 1 2 7. For example, the method of claim No. 126 in the patent application range, wherein the capacitor is then discharged. 12 8. For example, the method of claim 126, wherein the PIC microcontroller is programmed by a computer and connected to the computer, and wherein the computer provides a user interface for controlling and monitoring the UV-visible absorption analysis . 12 9. -An optical unit for performing spectroscopic analysis of one or more test solutions, comprising: a first fluid chamber of a first capacity; a first fluid chamber for introducing one or more test solutions connected to the first fluid chamber; Or multiple fluid inlets; 84 326 \ Patent Specification (Supplements) \ 92 · 〇5 \ 92] 04018 200306418 is connected to one of the first fluid chambers and one of the second fluid chambers, the second fluid chamber is more than The first volume is small; a fluid outlet connected to the second fluid chamber for discharging the one or more test solutions; and for mixing the one or more fluid in the first and / or the second fluid chamber as needed A fluid mixing device for each test solution; for irradiating light to one of the second fluid chambers and for illuminating a light source; for detecting light transmitted or emitted by the one or more test solutions in the second fluid chamber A light detector connected to the illuminating light source; and a computing device connected to the light detector for collecting an absorption spectrum of the one or more test solutions and performing a spectral analysis based on the light spectrum if necessary. 1 3 0. For example, the optical unit in the patent application No. 129, wherein the second capacity is in a range from about 1/5 to about 1/2 of the first capacity. 1 3 1. For example, the optical unit according to the scope of patent application No. 129, wherein the one or more test solutions include one or more components of a solder plating solution. 13 2. For example, the optical unit according to claim 129, wherein the one or more test solutions include a sample solder plating solution. 1 3 3. For example, the optical unit of the patent application No. 132, wherein the optical unit further includes an opaque polymer cover covering the outer surfaces of the first and second fluid chambers. 1 3 4. For example, the optical unit of the patent application No. 133, wherein the opaque polymer cover is a black polyvinyl chloride cover. 1 3 5. For example, the optical unit of the scope of patent application No. 132, wherein the optical unit further includes an anti-85 326 on the inner surface of each of the first and the second fluid chamber \ Patent Specification (Supplement) \ 92-05 \ 92] 04018 200306418 Corrosive lining. The resist U6 is an optical unit according to the scope of patent application No. 135, wherein the neutral lining material includes tetrafluoroacetamidine. 1 37 · —A method for determining the concentration of components in a sample solder plating solution based on Raman spectroscopy. 138. For example, the method of claim 137, wherein the Raman spectroscopy analysis of the sample solder plating solution uses a single-mode Raman spectroscopy including a high-intensity luminous source, a sample illumination, a wooden needle, and a light s-spectrometer. Systematic. U9. For example, the method of claim ^, wherein the sample illumination probe of the single-mode Raman spectroscopy system includes a fiber optic bundle. 14 0. For example, the method of applying for item 137 of the patent scope includes the step of incorporating a Raman spectrophotometer into an analysis unit, wherein the analysis unit allows the sample Dn to flow through, and the analysis unit includes Inlet and outlet valves that isolate the unit from the sample plating solution during calibration or cleaning procedures. 1 4 1 · The method according to item 7 of the scope of patent application, including the following steps: U) irradiating the sample welding solution in the analysis unit with radiant energy from the high-intensity irradiation source; (b) using the pull A Mann spectrophotometer detects the intensity of radiant energy scattered by a specific component of the sample solder plating solution; and (c) determines the specific component in the sample solder plating solution based on the intensity of the radiant energy scattered by the specific component. Of the concentration. 1 4 2.  -An electrode assembly for measuring the potential of a sample solder plating solution, including: 86 326 \ Patent Specification (Supplement) \ 92-〇5 \ 921040] 8 200306418 (a)-the first measurement electrode; (b) the A measuring device arranged to be detachably connected to the first measuring electrode for measuring the potential of the sample solder plating solution; (c) a second auxiliary electrode; and (d) arranged to be detachably connected to the The first and second electrodes are used to pass current through a current source, wherein the first measurement electrode is connected to the measurement device and immersed in the sample solder plating solution during a potential measurement cycle, and wherein the first and After the measurement cycle, the second electrode is connected to the current source and immersed in a conductive electrolyte solution to clean the first electrode on the line. 1 4 3. For example, the electrode combination of claim No. 142, wherein the first and second electrodes include plutonium or a uranium alloy. 144. For example, the electrode assembly of claim 142, wherein the conductive electrolyte solution includes an acid solution. 87 326 \ Patent Specification (Supplement) \ 92-05 \ 921040】 8