[go: up one dir, main page]

WO2002033389A1 - Procedes pour l'evaluation non destructive de defauts dans un revetement transparent - Google Patents

Procedes pour l'evaluation non destructive de defauts dans un revetement transparent Download PDF

Info

Publication number
WO2002033389A1
WO2002033389A1 PCT/US2001/020375 US0120375W WO0233389A1 WO 2002033389 A1 WO2002033389 A1 WO 2002033389A1 US 0120375 W US0120375 W US 0120375W WO 0233389 A1 WO0233389 A1 WO 0233389A1
Authority
WO
WIPO (PCT)
Prior art keywords
sensor layer
oxygen
transparent coating
fluorophore
coating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2001/020375
Other languages
English (en)
Inventor
Radislav Alexandrovich Potyrailo
Argemiro Soares Dasilva Sobrinho
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Priority to AU2001271500A priority Critical patent/AU2001271500A1/en
Publication of WO2002033389A1 publication Critical patent/WO2002033389A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/8422—Investigating thin films, e.g. matrix isolation method
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00583—Features relative to the processes being carried out
    • B01J2219/00603—Making arrays on substantially continuous surfaces
    • B01J2219/00605—Making arrays on substantially continuous surfaces the compounds being directly bound or immobilised to solid supports
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00583—Features relative to the processes being carried out
    • B01J2219/00603—Making arrays on substantially continuous surfaces
    • B01J2219/00605—Making arrays on substantially continuous surfaces the compounds being directly bound or immobilised to solid supports
    • B01J2219/0061—The surface being organic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00583—Features relative to the processes being carried out
    • B01J2219/00603—Making arrays on substantially continuous surfaces
    • B01J2219/00605—Making arrays on substantially continuous surfaces the compounds being directly bound or immobilised to solid supports
    • B01J2219/00612—Making arrays on substantially continuous surfaces the compounds being directly bound or immobilised to solid supports the surface being inorganic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00583—Features relative to the processes being carried out
    • B01J2219/00603—Making arrays on substantially continuous surfaces
    • B01J2219/00605—Making arrays on substantially continuous surfaces the compounds being directly bound or immobilised to solid supports
    • B01J2219/00632—Introduction of reactive groups to the surface
    • B01J2219/00635—Introduction of reactive groups to the surface by reactive plasma treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00583—Features relative to the processes being carried out
    • B01J2219/00603—Making arrays on substantially continuous surfaces
    • B01J2219/00659—Two-dimensional arrays
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/0068—Means for controlling the apparatus of the process
    • B01J2219/00702—Processes involving means for analysing and characterising the products
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00274—Sequential or parallel reactions; Apparatus and devices for combinatorial chemistry or for making arrays; Chemical library technology
    • B01J2219/00718—Type of compounds synthesised
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
    • G01N21/64—Fluorescence; Phosphorescence
    • G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
    • G01N2021/6432—Quenching
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
    • G01N21/64—Fluorescence; Phosphorescence
    • G01N21/645—Specially adapted constructive features of fluorimeters
    • G01N21/6456—Spatial resolved fluorescence measurements; Imaging
    • G01N2021/646—Detecting fluorescent inhomogeneities at a position, e.g. for detecting defects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
    • G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
    • G01N2021/7769—Measurement method of reaction-produced change in sensor
    • G01N2021/7786—Fluorescence
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
    • G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
    • G01N2021/7793—Sensor comprising plural indicators

Definitions

  • the present invention in general relates to a method for nondestructive evaluation of defects in a transparent coating, and more particularly to a method for nondestructive evaluation of defects in a transparent coating by applying a sensor layer comprising a fluorophore under the transparent coating.
  • This method may be also used in combinatorial discovery of coating materials for applications as barrier, sensor, and other types of coatings.
  • Transparent coatings on polymers are increasingly being used as permeation barriers, and for various other functional uses such as protective coatings on spacecraft materials.
  • transparent barrier coatings are the subject of increasing interest in the packaging, pharmaceutical, optical, aerospace and electronics industries.
  • transparent coatings applied by Plasma Enhanced Chemical Vapor Deposition (PECVD), reactive evaporation, sputtering, etc. provide excellent barrier properties even when they are extremely thin.
  • PECVD Plasma Enhanced Chemical Vapor Deposition
  • SiO2 silicon dioxide
  • Si3N4 nitride
  • some residual permeation is observed, even when the barrier coatings are relatively thick. See, A.S. da Silva Sobrinho, M. Latreche, G. Czeremuszkin, J.E. Klemberg-Sapieha, M.R. Wertheimer, J. Vac. Sci. Technol. A16 (1998) 3190.
  • the residual permeation is attributed to the presence of microscopic defects in the coating.
  • an opaque coating such as aluminized polyester (PET)
  • PET aluminized polyester
  • RIE treatment technique the polymer underneath a defect region is etched by atomic oxygen (AO) creating a cavity that renders the defect visible by optical microscopy.
  • AO atomic oxygen
  • the transparent coating is coated with a thin layer of corn starch and the other side is exposed to iodine vapor.
  • the iodine that diffuses through the cavities underneath defects react with the corn starch giving a dark coloration and then a finger print of the defects in the sample. While this technique is effective in detecting defects in transparent coatings on transparent substrates, the RIE technique is destructive by nature rendering samples unsuitable for further analysis, it requires multiple steps in sample preparation, utilizes a high-cost plasma system, and does not allow a real time monitoring of oxygen permeation through defects.
  • Another advantages of the present invention is to use a method of nondestructive evaluation of defects in a combinatorial chemistry.
  • the techniques of combinatorial synthesis of libraries of organic compounds are well known.
  • Pirrung et al. developed a technique for generating arrays of peptides and other molecules using, for example, light-directed, spatially-addressable synthesis techniques (U.S. Pat. No. 5,143,854 and PCT Publication No. WO 90/15070).
  • Fodor et al. have developed automated techniques for performing light- directed, spatially-addressable synthesis techniques, photosensitive protecting groups, masking techniques and methods for gathering fluorescence intensity data (Fodor et al, PCT Publication No. WO 92/10092).
  • polypeptide arrays are synthesized on a substrate by attaching photoremovable groups to the surface of the substrate, exposing selected regions of the substrate to light to activate those regions, attaching an amino acid monomer with a photoremovable group to the activated region, and repeating the steps of activation and attachment until polypeptides of the desired length and sequences are synthesized.
  • the Pirrung et al. method is a sequential, step-wise process utilizing attachment, masking, deprotecting, attachment, etc.
  • Such techniques have been used to generate libraries of biological polymers and small organic molecules to screen for their ability to specifically bind and block biological receptors (i.e., protein, DNA, etc.).
  • These solid phase synthesis techniques which involve the sequential addition of building blocks (i.e., monomers, amino acids) to form the compounds of interest, cannot readily be used to prepare many inorganic and organic compounds.
  • building blocks i.e., monomers, amino acids
  • Schultz et al. applied combinatorial chemistry techniques to the field of material science U.S. Pat. No. 5,985,356. More particularly, Schultz et al. disclose methods and apparatus for the preparation and use of a substrate having thereon an array of diverse materials in predefined regions.
  • An appropriate array of materials is generally prepared by delivering components of materials to predefined regions on the substrate and simultaneously reacting the reactants to form different materials. Once prepared, the array of materials can be screened in parallel for materials having useful properties. Properties which can be screened for include, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, etc.
  • Sdknning detection systems suggested in Schultz et al. for use in screening method include scanning Raman spectroscopy; scanning NMR spectroscopy; scanning probe spectroscopy including, for example, surface potentialometry, tunnelling current, atomic force, acoustic microscopy, shearing-stress microscopy, ultra fast photo excitation, electrostatic force microscope, tunneling induced photo emission microscope, magnetic force microscope, microwave field-induced surface harmonic generation microscope, nonlinear alternating-current tunnelling microscopy, near- field scanning optical microscopy, inelastic electron tunneling spectrometer, etc.; optical microscopy at different wavelengths; scanning optical ellipsometry (for measuring dielectric constant and multilayer film thickness); scanning Eddy-current microscope; electron (diffraction) microscope, etc.
  • one of the following devices can be used: a Scanning RF Susceptibility Probe, a Scanning RF/Microwave Split-Ring Resonator Detector, or a Scanning Superconductors Quantum Interference Device (SQUID) Detection System.
  • a nanoindentor diamond tip
  • a Scanning RF/Microwave Spilt-Ring Resonator Detector or a SQUID Detection System can be used.
  • crystallinity infrared or Raman spectroscopy can be used.
  • a Scanning RF Susceptibility Probe a Scanning RF Microwave Split-Ring Resonator Detector, a SQUID Detection System or a Hall probe can be used.
  • a photodetector can be used.
  • the present invention provides a method for nondestructive evaluation of defects in transparent coatings, which is free from the limitations of known techniques for evaluation of defects in transparent coatings.
  • a method for nondestructive evaluation of defects in a transparent coating comprising applying a sensor layer comprising a fluorophore under the transparent coating, and exposing the transparent coating to molecular oxygen, wherein the
  • defects are identified by change in the fluorescence signature of the fluorophore in locations corresponding to the coating defects.
  • the present invention can be also used to map and count defect density and to better understand the origins of defects in transparent coatings on a microscopic scale.
  • the present invention also avails itself to use in rapidly screening a number of samples in a combinatorial array.
  • Fig. 1 illustrates an absorption spectrum of platinum (II) octaethyl porphyrin in chloroform.
  • Fig. 2 illustrates fluorescence spectra of platinum (II) octaethylporphyrin in a thin polycarbonate film in nitrogen and oxygen environment.
  • Fig. 3 illustrates a sensor response to different oxygen concentrations.
  • Fig. 4 illustrates reversibility of sensor response to oxygen and nitrogen.
  • Fig. 5 illustrates principle of spatial mapping of oxygen permeability through a library of transparent coatings.
  • Fig. 6 illustrates principle of spatial mapping of oxygen permeability through a library of transparent coatings.
  • Fig. 7 illustrates principle of spatial mapping of oxygen permeability through a library of transparent coatings.
  • Fig. 8 illustrates fluorescence image of the coating grid when the grid of transparent coatings was exposed to air. Asterisks indicate the positions of deposited silicon nitride barrier coatings.
  • Fig. 9 illustrates fluorescence image of the coating grid when the grid of transparent coatings was exposed to nitrogen. Asterisks indicate the positions of deposited silicon nitride barrier coatings.
  • Fig. 10 illustrates oxygen-permeability map for the grid of silicon nitride barrier coatings produced as the ratio of two fluorescence images of the coating grid when the coating was exposed to nitrogen and oxygen.
  • Fig. 11 illustrates spatial mapping of defects in barrier coatings. Edge- induced diffusion of oxygen is also clearly visible.
  • the present invention is based on the understanding that fluorescence quenching of certain fluorophores upon their exposure to molecular oxygen can be used for detection of defects in coating layers.
  • Certain types of fluorophores are known to provide an efficient quenching by molecular oxygen when dissolved in solvents or in a variety of polymer matrices.
  • the absorption and fluorescence spectra of platinum (II) octaethylporphyrin fluorophore are illustrated in figures 1 and 2.
  • Sensor response to different oxygen concentrations is presented in figure 3.
  • Sensor reversibility upon changes the gas from nitrogen to oxygen at different concentrations is illustrated in figure 4. Fluorescence intensity and lifetime of such fluorophore decrease with increasing oxygen concentration.
  • This fluorescence response can serve as a robust and predictable meter for the amount of oxygen around the fluorophore, which is caused by the defects in surface coating layers.
  • fluorescence spectroscopy the present invention provides advantages over the prior art techniques including the following:
  • the preferred embodiments of the present invention provide a method for nondestructive -evaluation of defects in a barrier coating comprising applying a sensor layer comprising a fluorophore under a grid or an array of the barrier coatings; and exposing the barrier coating to molecular oxygen, wherein the defects are identified by change in the fluorescence signature of the fluorophore in locations corresponding to the coating defects.
  • the invention is described herein primarily with regard to the detection of defects on barrier coatings, but readily be applied in the detection of other coatings.
  • a sensor layer may be applied between a barrier coating and a substrate. In another embodiment, a sensor layer may be applied onto a substrate such that a substrate is placed between the sensor layer and a barrier coating.
  • various types of other coating layers may be also applied under or onto a substrate, a sensor layer or a barrier coating.
  • a sensor layer comprises at least one class of fluorophores.
  • One class of fluorophores includes porphyrins.
  • the porphyrins include but are not limited to platinum or palladium porphyrins, such as platinum(II) octaethylporphyrin (Pt-OEP) and palladium(II) octaethylporphyrin (Pd-OEP).
  • P. Hartmann, W. Trettnak Effects of polymer matrices on calibration functions of luminescent oxygen sensors based on porphyrin ketone complexes, Anal. Chem. 1996, 68, 2615-2620; A. Mills, A. Lepre, Controlling the response characteristics of luminescent porphyrin plastic film sensors for oxygen, Anal. Chem. 1997, 69, 4653-4659.
  • fluorophores includes polycyclic aromatic hydrocarbons. Examples of this class of fluorophores are described in I. B. Berlman, Handbook of fluorescence spectra of aromatic molecules, Academic Press, New York, NY, 1971; O. S. Wolfbeis, In Fiber Optic Chemical Sensors and Biosensors; O. S. Wolfbeis, Ed.; CRC Press: Boca Raton, FL, 1991; Vol. 2; pp 19-53.
  • Preferred fluorophores of this class include pyrene, pyrenebutyric acid, fluoranthene, decacyclene, diphenylanthracene, and benzo(g,h,I)perylene.
  • fluorophores includes a variety of long- wave absorbing dyes such as perylene dibutyrate, and heterocycles including fluorescent yellow, trypaflavin and other heterocycle compounds as described in O. S. Wolfbeis, In Efber Optic Chemical Sensors and Biosensors; O. S. Wolfbeis, ⁇ d.; CRC Press:
  • fluorophores includes metal-organic complexes of ruthenium, osmium, iridium, gold and platinum as described in O. S. Wolfbeis, In Ez ' ber Optic Chemical Sensors and Biosensors; O. S. Wolfbeis, ⁇ d.; CRC Press: Boca Raton, FL, 1991; Vol. 2; pp 19-53, J. N. Demas, B. A. Degraff, P. B. Coleman,
  • Oxygen sensors based on luminescence quenching Anal. Chem. 1999, 71, 793A- 800A, and J. N. Demas, B. A. DeGraff, Design and applications of highly luminescent transition metal complexes, Anal. Chem. 1991, 63, 829A-837A; A. Mills, A. Lepre, B. R. Theobald, ⁇ . Slade, B. A. Murrer, Use of luminescent gold compounds in the design of thin-film oxygen sensors, Anal. Chem. 1997, 69, 2842-
  • Fluorophores are incorporated into a sensor layer formed from film- forming polymeric material.
  • the material for the sensor layer may affect the properties of sensors such as selectivity, sensitivity, and limit of detection.
  • suitable material for the sensor layer is selected from polymeric material capable of providing required response time, oxygen permeability, oxygen solubility, degree of transparency and hardness.
  • polymers that can be used as matrices for oxygen sensors can be divided into several classes as described in S. A. Stern, B. Krishnakumar, S. M. Nadakatti, In Physical Properties of Polymers Handbook; J. E. Mark, Ed.; AIP Press: New York, 1996; pp 687-700.
  • Such classes include polyolefins, vinyl and vinylidene polymers, natural and synthetic rubbers, polyesters, polycarbonates, cellulose derivatives, fluoropolymers, polyorganosiloxanes, polynitriles, polyamides, polyimides, polyurethanes, polyoxides, polysulfones, polyacetylenes, polyacrylics.
  • polystyrene-co-TFEM fluoro-polymer
  • silicones silicone blends, silicone copolymers, cation exchange membranes such as Nafion, and others.
  • the sensor layer is made of thin film, suitably of a thickness from 0.05 to 1000 micrometers, particularly from 0.5 to 100 micrometers, and more particularly from 1 to 10 micrometers.
  • the sensor layer is formed by incorporating fluorophores into the polymeric material for the sensor layer. Incorporation of the fluorophores may be carried out by dissolving a fluorophore in a solution of polymeric material and then the resultant solution is applied to a substrate to form a sensor layer using various methods using thin-film deposition techniques that are explained below.
  • Solvents can be either polar or non polar, including but not limited to water, ethanol, methanol, acetone, chloroform, toluene, benzene, and hexane.
  • Another method for incorporation of fluorophores includes dissolving a fluorophore in a suitable solvent and immersing a polymer film into the fluorophore solution.
  • the polymer film swells in the solvent and some of the fluorophore molecules penetrate into the swollen polymer film. Upon drying, the solvent is removed while the fluorophore remains trapped in the polymer film.
  • the sensor layer is exposed to varying concentrations of oxygen.
  • Oxygen concentrations range from 0 to 100 % by volume.
  • Partial pressure of oxygen can range from 0 to 1 atmosphere. However, in order to accelerate penetration of oxygen, the partial pressure can be increased higher than 1 atmosphere and, depending on the equipment used, can be, for example 10, 100, or 1000 atmosphere or even higher.
  • the sensor layer may be exposed first to the atmosphere at which the coating deposition was performed, and then to nitrogen or oxygen.
  • the change in fluorescence intensity or lifetime may be measured using a spectrometer such as Shimadzu F-5300PC, Hitachi F-4010, Edinburgh Analytical Instruments FL-900, SPEX Fluorog 2, Perkin Elmer LS50B, and others. Fluorescence of fluorophores is excited using a light source from the spectrometer which typically a xenon arc lamp and/or xenon argon or discharge lamp with a power from 150W to 20kW.
  • Tungsten lamp different diodes cover range from 370 to 1500 nm
  • Light emitting diodes different diode lasers cover range from about 400 to 1500
  • Argon ion laser several lines over 350 - 514 nm
  • Helium-neon laser several lines over 543 - 633 nm
  • Oxygen sensitive materials, fluorophores, used in the present invention are excited at wavelengths ranging from about 300 to 650 nm. A comparison of fluorescence values is made for the coating library exposed to different concentrations of oxygen at different times .
  • a sensor response is defined as the ratio of fluorescence intensity of the fluorophore in nitrogen to fluorescence intensity of the fluorophore in a given oxygen-containing environment.
  • fluorescence measurements were performed on a setup which included a white light source (450-W Xe arc lamp, SLM Instruments, Inc., Urbana, IL, Model FP-024), a monochromator for selection of the excitation wavelength (SLM Instruments, Inc., Model FP-092), and a portable spectrofluorometer (Ocean Optics, Inc., Dunedin, FL, Model ST2000).
  • the spectrofluorometer was equipped with a 200- ⁇ m slit, 600-grooves/mm grating blazed at 400 nm and covering the spectral range from 250 to 800 run with efficiency greater than 30%, and a linear CCD-array detector.
  • Excitation light from the monochromator was focused into one of the arms of a "six-around-one" bifurcated fiber-optic reflection probe (Ocean Optics, Inc., Model R400-7-UV/VIS). Emission light was collected from a sample when the common end of the fiber-optic probe was positioned near the sample at a certain angle to minimize the amount of excitation light reflected from the sample back into the probe.
  • the second arm of the probe was coupled to the spectrofluorometer.
  • a flow cell with transparent viewing windows was used to position samples of fluorescent material. Different oxygen concentrations were generated by diluting pure (100%) oxygen with a nitrogen carrier gas using flow mass controllers. Total flow was kept constant at 4 L/min. The gas was introduced into the flow cell. Fluorescent material was positioned in the flow cell.
  • the fluorescent material was a thin film of polycarbonate (PC) material (Scientific Polymer Products, Inc, Ontario, NY) with immobilized fluorescent dye Pt(II)Octaethylporphyrin (Porphyrin Products, Inc., Logan, UT) used as a fluorophore.
  • PC polycarbonate
  • Materials for barrier coatings include, but are not limited to oxides, nitrides and oxinitrides of silicon, aluminum, zinc, boron and other metals, ceramics, polyvinyl alcohol, ethylene vinyl alcohol copolymers, polyvinyl dichloride, different types of nylon, cellophane, polyethylene terephtalate, PVC, PCTFE, polypropylene, and others.
  • Fig. 5 details one embodiment where a library of transparent coatings 3 is deposited onto the sensor layer 2, which, in turn, is formed onto a substrate 1.
  • Fig. 6 details another embodiment where a library of transparent coatings 3 is deposited onto one side of the substrate 1 while the sensor layer 2 is formed onto another side of the substrate 1.
  • Thin-film deposition techniques in combination with physical masking techniques or photolithographic techniques can be used to apply a barrier coating layer onto a sensor layer.
  • Such thin-film deposition techniques can generally be broken down into the following four categories: evaporative methods, glow discharge processes, gas-phase chemical processes, and liquid-phase chemical techniques. Included within these categories are, for example, sputtering techniques, spraying techniques, laser ablation techniques, electron beam or thermal evaporation techniques, ion implantation or doping techniques, chemical vapor deposition, techniques, as well as other techniques used in the fabrication of integrated circuits. All of these techniques can be applied to deposit highly uniform layers, i.e., thin- films, of the various coating materials on selected regions on the sensor layer.
  • such thin-film deposition techniques can be used to generate uniform gradients at each reaction region on the substrate or, alternatively, over all of the reaction regions on the substrate.
  • Thin-films of the various barrier coating materials can be deposited either onto the sensor layer or onto the substrate using evaporative methods in combination with physical masking techniques.
  • evaporative methods the following sequential steps take place: (1) a vapor is generated by boiling or subliming a target material; (2) the vapor is transported from the source to a substrate; and (3) the vapor is condensed to a solid film on the substrate surface.
  • Evaporants, i.e., target materials which can be used in the evaporative methods cover an extraordinary range of chemical reactivities and vapor pressures and, thus, a wide vary of sources can be used to vaporize the target materials.
  • Such sources include, for example, resistance-heated filaments, electron beams; crucible heated by conduction, radiation or rf-inductions; and arcs, exploding wires and lasers.
  • thin-film deposition using evaporative methods is carried out using lasers, filaments, electron beams or ion beams as the source. Successive rounds of deposition, through different physical masks, using evaporative methods can be used to generate a library or grid of barrier coatings on a sensory layer for detection of defects in the barrier coatings in combinatorial discovery of coating materials.
  • Molecular Beam Epitaxy is an evaporative method that can be used to grow epitaxial thin-films.
  • the films are formed on single- crystal substrates by slowly evaporating the elemental or molecular constituents of the film from separate Knudsen effusion source cells (deep crucibles in furnaces with cooled shrouds) onto substrates held at temperatures appropriate for chemical reaction, epitaxy and re-evaporation of excess reactants.
  • the Knudsen effusion source cells produce atomic or molecular beams of relatively small diameter which are directed at the heated substrate, usually silicon or gallium arsenide.
  • Fast shutters are interposed between the source cells and the substrates. By controlling these shutters, one can grow superlattices with precisely controlled uniformity, lattice match, composition, dopant concentrations, thickness and interfaces down to the level of atomic layers.
  • thin-films of the various barrier coating materials can be deposited onto the sensor layer or onto the substrate using glow-discharge processes in combination with physical masking techniques.
  • glow-discharge processes in combination with physical masking techniques.
  • the most basic and well known of these processes is sputtering, i.e., the ejection of surface atoms from an electrode surface by momentum transfer from bombarding ions to surface atoms.
  • Sputtering or sputter-deposition is a term used by those of skill in the art to cover a variety of processes, all of which can be used in the methods of the present invention.
  • One such process is RF/DC Glow Discharge Plasma Sputtering.
  • a plasma of energized ions is created by applying a high RF or DC voltage between a cathode and an anode.
  • the energy ions from the plasma bombard the target and eject atoms which are then deposited on a substrate, a sensor layer.
  • Ion-Beam Sputtering is another example of a sputtering process which can be used to deposit thin-films of the various barrier coating materials on a substrate. Ion-Beam Sputtering is similar to the foregoing process except the ions are supplied by an ion source and not a plasma.
  • sputtering techniques e.g., diode sputtering, reactive sputtering, etc.
  • glow- discharge processes can be used in the methods of the present invention to deposit thin-films on a substrate, a sensor layer.
  • Successive rounds of deposition, through different physical masks, using sputtering or other glow-discharge techniques can be used to generate a grid or library of barrier coatings on a sensor layer for detection of defects in the barrier coating for use of combinatorial discovery of coating materials.
  • CVD Chemical Vapor Deposition
  • Photo-Enhanced CVD based on activation of the reactants in the gas or vapor phase by electromagnetic radiation, usually short-wave ultraviolet radiation
  • Plasma-Enhanced CVD based on activation of the reactants in the gas or vapor phase using a plasma
  • Successive rounds of deposition, through different physical masks, using CVD technique can be used to generate a grid or library of barrier coatings on a sensor layer for detection of defects in the barrier coating in combinatorial discovery of coating materials.
  • thin-films of the various reactants can be deposited onto the sensor layer or onto the substrate using a number of different mechanical techniques in combination with physical masking techniques.
  • mechanical techniques include, for example, spraying, spinning, dipping, draining, flow coating, roller coating, pressure-curtain coating, brushing, etc.
  • spray-on and spin-on techniques are particularly useful.
  • Sprayers which can be used to deposit thin-films include, for example, ultrasonic nozzle sprayers, air atomizing nozzle sprayers and atomizing nozzle sprayer.
  • ultrasonic sprayers disc- shaped ceramic piezoelecric transducers covert electrical energy into mechanical energy.
  • the transducers receive electrical input in the form of a high-frequency signal from a power supply that acts as a combination oscillator/amplifier.
  • a power supply that acts as a combination oscillator/amplifier.
  • the nozzles intermix air and liquid streams to produce a completely atomized spray.
  • the nozzles use the energy from a pressurized liquid to atomize the liquid and, in turn, produce a spray.
  • Successive rounds of deposition, through different physical masks, using mechanical techniques, such as spraying can be used to generate a grid or library of barrier coatings on a sensor layer for detection of defects in combinatorial discovery of coating materials.
  • the barrier coating suitably has a thickness from 0.1 nm to 100 micrometers, particularly from 1 nm to 10 micrometers, and more particularly from 10 n-m to 1 micrometer.
  • FIG. 5 A principle of spatial mapping of oxygen permeability through a library of barrier coatings is depicted in Fig. 5.
  • Fig. 7 illustrates an example of an instrumentation used for spatial mapping of oxygen permeability through a library of transparent coatings.
  • a library of transparent coatings, sensor layer and substrate 11 is positioned in a gas cell 10.
  • a light source 12 emits light through an excitation wavelength selection element 13.
  • the excitation radiation 14 illuminates the library of transparent coatings, sensor layer and substrate 11.
  • the emission radiation 6 from the sensor layer is captured with an imaging detector 8 through an emission wavelength selection element 7.
  • Data is collected at low partial pressure of oxygen 9 and at high partial pressure of-oxygen 15.
  • Results of mathematical image processing that includes division operation 16 are analyzed to produce oxygen distribution map 17 and to identify defects in transparent coating 18.
  • Fluorescence mapping measurements were performed using a setup which included a white light source (450-W Xe arc lamp, SLM Instruments, Inc., Urbana, IL, Model FP-024), a monochromator for selection of the excitation wavelength (SLM Instruments, Inc., Model FP-092), and a CCD camera (Roper
  • the excitation wavelength for the fluorophore was selected using the monochromator and was directed to the sample. Sample fluorescence was collected with the camera. The excitation light was filtered out from being captured by the camera with an integration time of 1 s using a long pass optical filter that transmitted wavelengths above 610 nm.
  • Spatial maps of oxygen distribution in the barrier coatings were obtained by collecting fluorescence images of the sample with a grid of barrier coatings upon exposure of the sample to different oxygen concentrations (0 and 100%). Each image is represented in a digital two-dimensional format where each pixel in the image has its own recorded fluorescence intensity. Similar to the sensor signal which is defined as the ratio of fluorescence intensity of fluorophore in nitrogen to the fluorescence intensity of fluorophore in a given oxygen containing environment, the spatial map was obtained by dividing, pixel-by-pixel, the fluorescence intensities of corresponding pixels. The result was a new two- dimensional array of relative fluorescence values which represent an oxygen distribution map.
  • the range of integration times can be selected ranging from about 10 ns to about 1000 s.
  • the integration time depends on the available amount of fluorescence signal and the requirements for the signal-to-noise.
  • Fluorescence image map may be used to obtain density of defects on the library of coatings.
  • the ratio of fluorescence intensity of fluorophore under the coating in nitrogen to the fluorescence intensity of fluorophore under the coating in a given oxygen containing environment should be unity because the coating does not transport oxygen through it.
  • Oxygen permeation occurs in coating regions that have defects. This oxygen permeation is flagged by the fluorescence change of the fluorophore under the barrier coating with a defect.
  • the sections of the oxygen map of defect free regions will have a unity fluorescence ratio.
  • the regions of barrier coating with defects will have an increased fluorescence ratio proportional to the amount of oxygen diffused down to the oxygen sensitive layer under the barrier coating.
  • the density of defects is obtained by counting the regions with relative fluorescence intensity more than unity over a unit area.
  • Barrier coatings were deposited on top of the sensor layer which, in turn, was deposited onto a polycarbonate or quartz substrate. Several 6-mm wide stripes of silicon nitride barrier coatings were deposited in vacuum using a plasma- enhanced chemical vapor deposition onto the surface of the oxygen sensor.
  • the coating thickness was about 30 nm.
  • Fluorescence mapping measurements were performed using a setup which included a white light source (450-W Xe arc lamp, SLM Instruments, Inc., Urbana, IL, Model FP-024), a monochromator for selection of the excitation wavelength (SLM Instruments, Inc., Model FP-092), and a CCD camera (Roper Scientific, Trenton, NJ, Model TE/CCD 1100 PF/UV).
  • the excitation wavelength for the fluorophore was selected at 380 nm using the monochromator and was directed to the sample. Sample fluorescence was collected with the camera. The excitation light was filtered out from being captured by the camera using a long pass optical filter that transmitted wavelengths above 610 nm.
  • Fluorescence images of the coating grid upon exposure of the sensor to air and nitrogen are demonstrated in Figures 8 and 9, respectively. Fluorescence of the sensor region free from the deposited barrier coating is significantly quenched as indicated by the dark regions on the image. Upon exposure of the sensor to nitrogen, all sensor regions have the same fluorescence intensity indicating that no oxygen is present under the deposited coatings.
  • Spatial maps of oxygen distribution in the barrier coatings were obtained by collecting fluorescence images of the sample with a grid of barrier coatings upon exposure of the sample to different oxygen concentrations (0 and 100%), as illustrated in Fig. 7. Each image is represented in a digital two- dimensional format where each pixel in the image has its own recorded fluorescence intensity. Similar to the sensor signal which is defined as the ratio of fluorescence intensity of fluorophore in nitrogen to the fluorescence intensity of fluorophore in a given oxygen containing environment, spatial map was obtained by dividing pixel-by- pixel the fluorescence intensities of corresponding pixels. The result was a new two- dimensional array of relative fluorescence values which represents an oxygen distribution map.
  • a ratio of two images when the sensor was exposed to nitrogen and oxygen represents an oxygen-permeability map for the grid of barrier coatings. See Fig. 10.
  • the dark regions demonstrate that the fluorescence intensity under the barrier coatings was unchanged upon exposure of the grid to nitrogen and to oxygen.
  • Bright regions free from the coating, which show high levels of signal, demonstrate that the fluorescence was efficiently quenched upon exposure to oxygen from its original high level in nitrogen atmosphere.
  • the region of interest was selected the middle stripe of the three coatings in Example 1 because measurements obtained in Example 1, as shown in Figs. 8 and 9, indicated that there are several defects of different shape that may induce the degradation of the barrier properties of the coating.
  • the sequence of oxygen permeability maps was collected over 29 h after the exposure of the coating grid to oxygen. Results of spatial mapping of defects in barrier coatings at different times after the exposure of the coatings to oxygen are presented in Fig. 11. Edge- induced diffusion of oxygen is also clearly visible.

Landscapes

  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)

Abstract

L'invention concerne un procédé pour évaluer de façon non destructive des défauts dans un revêtement transparent (3) sur des polymères, consistant à appliquer une couche de détection (2) comprenant un fluorophore sous le revêtement transparent (3) et à exposer ledit revêtement transparent (3) à de l'oxygène moléculaire, les défauts étant identifiés à travers une modification de la signature de fluorescence du fluorophore à des endroits correspondant aux défauts de revêtement. Ce procédé peut être utilisé pour l'évaluation non destructive de défauts dans une bibliothèque de revêtements transparents (3) : une couche de détection (2) comprenant un fluorophore est appliquée sous une grille ou un réseau de revêtements transparents (3), lesquels sont exposés à différentes pressions partielles d'oxygène, ce qui permet de mapper et de calculer la densité de défauts et de mieux comprendre l'origine de ces défauts dans les revêtements à une échelle microscopique. Par ailleurs, ce procédé peut être utilisé efficacement pour effectuer un criblage rapide de défauts dans plusieurs échantillons à l'intérieur d'un réseau combinatoire.
PCT/US2001/020375 2000-10-19 2001-06-26 Procedes pour l'evaluation non destructive de defauts dans un revetement transparent Ceased WO2002033389A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2001271500A AU2001271500A1 (en) 2000-10-19 2001-06-26 Methods for nondestructive evaluation of defects in a transparent coating

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US69267300A 2000-10-19 2000-10-19
US09/692,673 2000-10-19

Publications (1)

Publication Number Publication Date
WO2002033389A1 true WO2002033389A1 (fr) 2002-04-25

Family

ID=24781532

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/020375 Ceased WO2002033389A1 (fr) 2000-10-19 2001-06-26 Procedes pour l'evaluation non destructive de defauts dans un revetement transparent

Country Status (2)

Country Link
AU (1) AU2001271500A1 (fr)
WO (1) WO2002033389A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1369682A2 (fr) * 2002-06-07 2003-12-10 Interuniversitair Microelektronica Centrum Vzw Procédé de detection de l'integrité d'une couche au niveau de plaquette

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0336029A1 (fr) * 1988-04-06 1989-10-11 Minnesota Mining And Manufacturing Company Procédé pour le contrôle fluorimétrique de couches fonctionnelles et structures utilisées dans ce procédé et comprenant un substrat et laditte couche fonctionelle
WO1995032060A1 (fr) * 1994-05-20 1995-11-30 Deardorff James R Systeme de revetement reagissant aux ultraviolets
US5483819A (en) * 1994-05-27 1996-01-16 W.R. Grace & Co.-Conn. Method of detecting the permeability of an object to oxygen
US5583047A (en) * 1992-12-10 1996-12-10 W. R. Grace & Co.-Conn. Method of detecting the permeability of an object to oxygen
US5985356A (en) * 1994-10-18 1999-11-16 The Regents Of The University Of California Combinatorial synthesis of novel materials
US6074607A (en) * 1996-04-01 2000-06-13 Bayer Corporation Oxygen sensing membranes

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0336029A1 (fr) * 1988-04-06 1989-10-11 Minnesota Mining And Manufacturing Company Procédé pour le contrôle fluorimétrique de couches fonctionnelles et structures utilisées dans ce procédé et comprenant un substrat et laditte couche fonctionelle
US5583047A (en) * 1992-12-10 1996-12-10 W. R. Grace & Co.-Conn. Method of detecting the permeability of an object to oxygen
WO1995032060A1 (fr) * 1994-05-20 1995-11-30 Deardorff James R Systeme de revetement reagissant aux ultraviolets
US5483819A (en) * 1994-05-27 1996-01-16 W.R. Grace & Co.-Conn. Method of detecting the permeability of an object to oxygen
US5985356A (en) * 1994-10-18 1999-11-16 The Regents Of The University Of California Combinatorial synthesis of novel materials
US6074607A (en) * 1996-04-01 2000-06-13 Bayer Corporation Oxygen sensing membranes

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1369682A2 (fr) * 2002-06-07 2003-12-10 Interuniversitair Microelektronica Centrum Vzw Procédé de detection de l'integrité d'une couche au niveau de plaquette

Also Published As

Publication number Publication date
AU2001271500A1 (en) 2002-04-29

Similar Documents

Publication Publication Date Title
Xie et al. Probing single molecule dynamics
Lettieri et al. The gas‐detection properties of light‐emitting diatoms
EP0485425B1 (fr) Appareil et microbase pour un systeme de spectroscopie de raman ameliore en surface et son procede de production
US8293340B2 (en) Plasma deposited microporous analyte detection layer
Merlen et al. Surface enhanced Raman spectroscopy of organic molecules deposited on gold sputteredsubstrates
US6383815B1 (en) Devices and methods for measurements of barrier properties of coating arrays
Quintero et al. Soft lithographic patterning of spin crossover complexes. Part 1: Fluorescent detection of the spin transition in single nano-objects
KR20090101289A (ko) 플라즈마 증착된 미공성 탄소 재료
Lensen et al. Aided Self‐Assembly of Porphyrin Nanoaggregates into Ring‐Shaped Architectures
Spadavecchia et al. Optochemical vapour detection using spin coated thin film of ZnTPP
Murray-Methot et al. Analytical and physical optimization of nanohole-array sensors prepared by modified nanosphere lithography
Ionov et al. Simple fluorescent sensor for simultaneous selective quantification of benzene, toluene and xylene in a multicomponent mixture
Jang et al. Multi-encoded rugate porous silicon as nerve agents sensors
US20040150827A1 (en) Device arrays and methods for operation in aggressive solvents and for measurements of barrier properties of plurality of coatings
US20070269611A1 (en) Systems and methods of combinatorial synthesis
US7903239B2 (en) Porous photonic crystal with light scattering domains and methods of synthesis and use thereof
IL286155A (en) Needle metal structures
US20030162179A1 (en) Fabrication, performance testing, and screening of three dimensional arrays of materials
Lowman et al. Nanoscale morphology of polyelectrolyte self-assembled films probed by scanning force and near-field scanning optical microscopy
WO2002033389A1 (fr) Procedes pour l'evaluation non destructive de defauts dans un revetement transparent
Nguyen et al. Programmable self-assembly of M13 bacteriophage for micro-color pattern with a tunable colorization
Lee et al. Ultraviolet plasmonic enhancement of the native fluorescence of tryptophan on aluminum nano-hole arrays
de Acha et al. Comparative study of polymeric matrices embedding oxygen-sensitive fluorophores by means of Layer-by-Layer nanosassembly
Henneberg et al. Investigation of azobenzene side group orientation in polymer surface relief gratings by means of photoelectron spectroscopy
Shvalya et al. Addressing SERS Challenges of Nanoplastics with Vertical Plasmonic Substrates

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP