JP3793221B2 - Manufacturing method of electron source substrate - Google Patents

Description

  The present invention relates to an electron beam apparatus and a method for manufacturing an electron source substrate used in an image forming apparatus such as an image display apparatus as an application thereof.

  This type of electron source substrate includes a plurality of electron-emitting devices that constitute an electron-emitting portion. In general, two types of electron-emitting devices are known: a thermionic source and a cold cathode electron source. Cold cathode electron sources include field emission elements (FE elements), metal / insulating layer / metal elements (MIM elements), surface conduction electron emission elements (SCE elements), and the like.

  The prior art by the present applicant will be introduced with regard to the technologies related to these. Patent Document 1 and Patent Document 2 relate to device fabrication by an ink jet forming method, and Patent Document 3 relates to an electron source substrate in which these devices are arranged in an XY matrix. This is described in detail in Patent Document 4. Further, the wiring forming method is described in detail in Patent Documents 5 and 6, and the element driving method is described in detail in Patent Document 7 and the like.

  FIG. 16 shows a typical device configuration of the surface conduction electron-emitting device as M.I. The element structure of Hartwell is shown. In the figure, 1 is a substrate, 2 and 3 are element electrodes, 4 is a conductive thin film, and 5 is an electron emission portion.

  The surface conduction electron-emitting device configured as described above has an advantage that a large number of devices can be formed over a large area because the structure is particularly simple and easy to manufacture among the cold cathode electron sources.

  As for the application of the surface conduction electron-emitting device, for example, image forming apparatuses such as an image display apparatus and an image recording apparatus, a charged beam source, and the like have been studied.

  In particular, as an application to an image display device, for example, as disclosed in Patent Documents 8 to 10, an image using a combination of a surface conduction electron-emitting device and a phosphor that emits light when irradiated with an electron beam. Display devices are being studied. An image display device using a combination of a surface conduction electron-emitting device and a phosphor has characteristics superior to those of other conventional image display devices.

  For example, compared with a liquid crystal display device that has been widespread in recent years, it is superior in that it is self-luminous and does not require a backlight and has a wide viewing angle. Further, since the structure is simple, it is particularly expected to be applied to an image forming apparatus having a large area.

  In general, this type of image forming apparatus often employs a configuration in which a spacer is disposed between a rear plate having an electron source substrate and a face plate having a phosphor or an anode member. Since a vacuum is set between the rear plate and the face plate, the atmospheric pressure is supported by a spacer having a sufficient mechanical strength so that the plate interval is kept constant. In particular, the role of the spacer becomes more important as the screen of the image forming apparatus becomes larger.

  However, this spacer may affect the trajectory of electrons flying between the rear plate and the face plate. The cause of the influence on the electron trajectory is the charging of the spacer. In spacer charging, a part of the electrons emitted from the electron source or the electrons reflected by the face plate enter the spacer, and secondary ions are emitted from the spacer, or ions ionized by the collision of the electrons adhere to the spacer surface. This is thought to be due to

  When the spacer is positively charged, electrons flying in the vicinity of the spacer are attracted to the spacer, so that the display image is distorted in the vicinity of the spacer. The effect of charging becomes more prominent as the distance between the rear plate and the face plate increases.

As a method for preventing this, a method of forming an electrode for electron trajectory correction on a spacer, a method of imparting conductivity to a charged surface, and removing a charge by passing a slight current are known. Patent Document 11 discloses a method of providing conductivity by coating the spacer surface with tin oxide. Patent Document 12 discloses a method of covering a spacer with a PdO glass material.
JP-A-9-102271 JP 2000-251665 A Japanese Patent Application Laid-Open No. 64-31332 JP-A-7-326311 JP-A-8-185818 Japanese Patent Laid-Open No. 9-50757 JP-A-6-342636 US Pat. No. 5,066,883 JP-A-2-257551 JP-A-4-28137 Japanese Patent Laid-Open No. 57-118355 JP-A-3-49135 JP 2000-21299 A Japanese Patent Laid-Open No. 10-334837

  The present applicant has been considering applying the ink jet apparatus technology to the manufacture of an electron source substrate having a surface conduction electron-emitting device. In this method, a metal-containing solution is applied in the form of droplets onto a substrate to form a conductive thin film, and an electron emission portion is formed in the conductive thin film. For example, Patent Document 13 proposes a technique for manufacturing a large-area electron source substrate with high throughput by simultaneously applying a plurality of droplets using an inkjet apparatus having a plurality of nozzles.

  However, the following problems remain in the above manufacturing method.

  The intervals between the plurality of nozzles provided in the ink jet apparatus are not necessarily constant. Therefore, the droplet application position (landing position) of the metal-containing solution differs depending on the individual nozzles. As a result, the position of the electron emission portion to be produced varies, and the image quality may be degraded. In particular, when such a variation occurs in a portion of the screen where important information is displayed, such as the central portion of the screen, a reduction in image quality is easily recognized, which is a problem as a display device. In addition, in the case of a display device using the above-mentioned spacer, a slight misalignment during the production of the electron emitting portion in the vicinity of the spacer has a large effect on the electron trajectory, causing distortion in the display image and a factor that significantly impairs the image quality. It was.

  In order to avoid such a problem, it is also conceivable to create a large-area electron source substrate using an extremely high-precision inkjet apparatus in which the droplet application positions of the nozzles are hardly different. However, in this case, since the yield of the ink jet apparatus itself is lowered, as a result, the cost of the electron source substrate is increased, which is also inconvenient.

  In addition, in the patent document 14, the present applicant has clarified that the distortion of the display image can be eliminated by adjusting the arrangement interval of the electron emitting portions in the vicinity of the spacer. However, when a conductive thin film is formed in a lump with an inkjet apparatus having a plurality of nozzles, the position of each electron emission portion cannot be individually controlled, and a high-quality electron source substrate is manufactured with high throughput. That was difficult.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique capable of producing a high-quality electron source substrate at low cost and high throughput.

  The manufacturing method of the electron source substrate of the present invention, which has been made to achieve the above object, has been made by intensive studies in order to solve the above-mentioned problems.

A first aspect of the present invention is a method of manufacturing an electron source substrate used in an image display device,
Forming a plurality of electrode pairs on a substrate;
Forming a conductive film by applying droplets containing a conductive substance between the electrodes of a plurality of electrode pairs using an inkjet apparatus having a plurality of heads having a plurality of nozzles; and
Forming an electron emission portion in the conductive film,
The application of the droplet is used for the first head used for the electrode pair on the substrate located at the edge of the screen and the electrode pair on the substrate located at least in the center of the screen. This is a method of manufacturing an electron source substrate, which is performed by simultaneously driving a second head having higher landing accuracy than that of the other head .

A second aspect of the present invention is a method of manufacturing an electron source substrate used in an image display device,
Forming a plurality of electrode pairs on a substrate;
Forming a conductive film by applying droplets containing a conductive substance between the electrodes of a plurality of electrode pairs using an inkjet apparatus having a plurality of heads having a plurality of nozzles; and
Forming an electron emission portion in the conductive film,
The application of the droplet is used for the first head used for the electrode pair on the substrate located at the edge of the screen and the electrode pair on the substrate located at least in the center of the screen. The electron source substrate manufacturing method is characterized in that it is performed by simultaneously driving a second head having a higher ejection amount accuracy than that of the first head .

  According to the present invention, a high-quality electron source substrate can be manufactured at low cost and high throughput.

  Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. The following electron source substrate is suitable for use as an electron source of an image forming apparatus such as an image display apparatus or an image recording apparatus, or as a charged beam source.

It should be noted that the dimensions, materials, shapes, and relative arrangements of the component parts described in the following embodiments are intended to limit the scope of the present invention only to those unless otherwise specified. is not.

(First reference form)
FIG. 1 is a schematic perspective view showing an image display device as an application example of the electron source substrate according to the first embodiment of the present invention.

  The image display device generally includes a rear plate 81 and a face plate 82.

  The rear plate 81 is provided with an electron source substrate 80 on which a plurality of electron emission portions are formed. The electron source substrate 80 includes a plurality of electron-emitting devices 87 arranged two-dimensionally in the X-direction and the Y-direction, and X-direction wiring 88 and Y-direction wiring for wiring these electron-emitting devices 87 in a simple matrix. 89. In the figure, for simplicity of explanation, only 5 × 4 20 electron-emitting devices 87 are shown, but actually, electron-emitting devices 87 on the order of several million to several tens of millions are arranged.

  The face plate 82 has a configuration in which a fluorescent film 84 and a metal back 85 are provided on the inner surface side (electron source substrate side) of the glass substrate 83. The metal back 85 is an anode member for accelerating electrons emitted from the electron source substrate 80 upon application of an acceleration voltage from the high voltage terminal Hv. The fluorescent film 84 is an image forming member that emits light upon irradiation with an electron beam.

  The rear plate 81, the support frame 86, and the face plate 82 are bonded with frit glass and sealed by baking at 400 to 500 ° C. for 10 minutes or more, thereby producing the envelope 90 of the image display device. The inside of the envelope 90 is set to a vacuum state.

  At this time, a spacer 91 as a support is installed between the face plate 82 and the rear plate 81 in order to form an envelope 90 having sufficient strength against atmospheric pressure even in the case of a large area panel. To do. As shown in the figure, the spacer 91 is fixed on a predetermined X-direction wiring. In this way, by disposing the face plate 82 so as to face the electron source substrate 80 via the spacer 91, the distance between the electron emitting portion and the fluorescent film 84 is kept constant over the entire screen, and there is no distortion. Image formation is possible.

  Next, the configuration and manufacturing method of the electron source substrate described above will be described in detail.

  FIG. 2 is a schematic view showing an electron source substrate and an ink jet apparatus used for producing the electron source substrate. FIG. 3 is a schematic view showing a surface conduction electron-emitting device that constitutes an electron-emitting portion of the electron source substrate.

  The electron source substrate has a configuration in which a plurality of surface conduction electron-emitting devices are two-dimensionally arranged. Each electron-emitting device includes an electrode pair made up of device electrodes 2 and 3 formed on the substrate 1, a conductive thin film 4 formed between the electrodes of the electrode pair, and an electron formed on the conductive thin film 4. The discharge part 5 is comprised. The element electrodes 2 of the electron emission elements arranged in the horizontal direction in FIG. 2 are connected to the same X-direction wiring 11, and the element electrodes 3 of the electron emission elements arranged in the vertical direction are the same. Connected to the Y-direction wiring 10.

The distance between the device electrodes 2 and 3 is preferably set to several tens nm to several hundreds μm. Moreover, it is desirable that the voltage applied between the device electrodes 2 and 3 is low, and it is required that the device electrode can be manufactured with good reproducibility. The lengths of the device electrodes 2 and 3 are preferably several μm to several hundred μm in view of the resistance value of the electrodes and the electron emission characteristics. The film thickness of the device electrodes 2 and 3 is preferably several tens of nm to several μm.

The conductive thin film 4 which is a part including the electron emission portion 5 is particularly preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics. The film thickness is appropriately set depending on the device electrodes 2 and 3 and energization forming conditions described later, but preferably 1 nm (10 angstroms) to 50 nm (500 angstroms). Moreover, the sheet resistance value is preferably 10 ³ to 10 ⁷ Ω / □. The sheet resistance value is defined as a resistance value in terms of unit thickness (in mm) of a conductor having the same length and width.

  As shown in FIG. 4, the ink jet devices 109 and 110 discharge and apply a droplet 8 containing a conductive material between the electrodes of the element electrodes 2 and 3 formed on the substrate 1 in advance, thereby forming a conductive thin film. It is used when forming.

  The ink jet devices 109 and 110 may be any device as long as they can form arbitrary liquid droplets. In particular, the discharge amount can be controlled in the range of about several tens of ng to several tens of ng. An ink jet apparatus that can easily form a minute droplet of about 10 ng or more is preferable. The droplet material may be in any state as long as the droplet can be formed, but a solution, an organometallic solution, or the like in which a metal or the like is dispersed and dissolved in water, a solvent, or the like may be used. it can.

  Specifically, the ink jet forming method using the ink jet apparatus is performed according to the following procedure.

  First, after the insulating substrate 1 is sufficiently washed with an organic solvent and dried, as shown in FIG. 5, a plurality of electrode pairs (element electrodes 2, 3) are formed on the substrate 1 by using a vacuum deposition technique and a photolithography technique. ).

  Next, as shown in FIG. 6, Y-direction wirings 10 are formed so as to electrically connect a plurality of element electrodes 3 arranged in the vertical direction (Y direction).

  Thereafter, as shown in FIG. 7, an interlayer insulating layer 6 is formed. The interlayer insulating layer 6 is for insulating the Y-direction wiring 10 and the X-direction wiring 11 formed in a later process, and is formed so as to cover the intersection where both wirings overlap. In addition, a contact hole is provided in the connecting portion so that the X-directional wiring 11 and the element electrode 2 can be electrically connected.

  Subsequently, as shown in FIG. 8, X-direction wirings 11 are formed so as to electrically connect a plurality of element electrodes 2 arranged in the horizontal direction (X direction). The substrate manufactured through the above steps is called an MTX substrate (matrix substrate).

  A conductive thin film is formed on the MTX substrate using the inkjet devices 109 and 110.

  In the image display apparatus according to the present embodiment, spacers 91 are arranged on predetermined X-direction wirings (in FIG. 2, the corresponding X-direction wirings are indicated by reference numeral 115). As described above, the electron-emitting devices in the vicinity of the spacer, particularly in the row adjacent to the spacer (hereinafter referred to as the first adjacent row), and the row next to the first adjacent row due to the influence of the charging of the spacer during electron emission, etc. The electron orbit of the electron-emitting device (hereinafter referred to as the second adjacent row) is bent, and the image tends to be distorted. Therefore, higher positional accuracy is required for the conductive thin films of the elements disposed in the first and second adjacent rows than the elements in other regions. In other words, the electron-emitting devices arranged in the vicinity of the fixed position of the spacer have a very small tolerance for positional deviation compared with the devices arranged in other regions.

  Therefore, in this reference embodiment, when applying droplets, at least for the device electrode pairs in the first and second adjacent rows arranged near the fixed position of the spacer, what are the other device electrode pairs? Different types of ink jet devices are used.

  Specifically, as shown in FIG. 2, a combination of different types of inkjet devices 109 and 110 is used, and the inkjet device 109 uses the first and second adjacent rows (the row indicated by A in the figure). ), And the conductive thin film in the other rows (rows indicated by B in the drawing) is formed by the inkjet apparatus 110.

  Here, as the ink jet device 109, a device having superior performance such as landing accuracy and discharge amount accuracy as compared with the ink jet device 110 is used. That is, the nozzles 112 of the inkjet device 110 are arranged with an accuracy that roughly matches the spacing between the rows of the previously produced MTX substrate, whereas the nozzles 111 of the inkjet device 109 are distorted in the image near the spacer. The conductive thin film 4 is arranged with high positional accuracy so as not to occur.

  The number of nozzles of the ink jet device 109 is set to four nozzles necessary and sufficient to collectively produce the conductive thin films in the first and second adjacent rows. On the other hand, the ink jet apparatus 110 has 20 nozzles (in FIG. 2, only 4 nozzles are omitted). The nozzles 111 and 112 of the respective ink jet devices 109 and 110 are arranged in a direction orthogonal to the spacer arrangement direction.

  Then, using a unit in which the inkjet device 110 is fixed to both sides of the nozzle arrangement direction of the inkjet device 109, a conductive thin film is simultaneously formed between a plurality of (44) electrodes in the (three) inkjet devices 110, 109, 110. Inject and apply droplets of the material solution that forms 4.

  At this time, as shown in FIG. 9A, by applying droplets while moving the unit and the substrate relative to each other along the spacer arrangement direction, the process for the device electrode pairs for 44 rows is collectively performed. And fast. In the figure, a hatched portion denoted by reference numeral 113 indicates a region in the vicinity of the X-directional wiring 115 in which the spacer is disposed (region where droplets are applied by the ink jet device 109), and hatched by reference number 114 The portion indicates other regions (regions where droplets are applied by the inkjet devices 110 and 110).

  When the processing for 44 rows is completed, the unit positions are offset relative to each other as shown in FIG. By repeating this, after applying droplets between the electrode pairs of the device electrodes on the entire surface of the substrate, heat treatment is performed at a temperature of 300 to 600 ° C., and the solvent is evaporated to form the conductive thin film 4 (FIG. 10). ).

  Subsequently, an electron emission portion 5 is formed in the conductive thin film 4. The electron emission portion 5 is a high-resistance crack formed in a part of the conductive thin film 4 and is formed by energization forming or the like. The crack may have conductive fine particles having a particle size of several hundred pm to several tens of nm. The conductive fine particles contain at least a part of elements constituting the conductive thin film 4. Moreover, the electron emission part 5 and the conductive thin film 4 in the vicinity thereof may contain carbon or a carbon compound.

  The energization forming is a process of forming the electron emission portion 5 which is a portion where the structure is changed by energizing the element electrodes 2 and 3 to cause a crack in the conductive thin film 4.

  A voltage waveform used for the forming process will be briefly described. FIG. 11 is an explanatory diagram showing a forming waveform.

  Here, a pulse waveform voltage is applied. There are a method of applying a pulse having a constant pulse peak value (FIG. 11 (a)) and a method of applying a pulse peak value while increasing the pulse peak value (FIG. 11 (b)). be able to.

  In the figure, T1 indicates the pulse width of the voltage waveform, and T2 indicates the pulse interval. In the method of FIG. 11A, T1 is set to 1 μsec to 10 msec, T2 is set to 10 μsec to 100 msec, and the peak value of the triangular wave (peak voltage at the time of forming) is appropriately selected. On the other hand, in the method of FIG. 11B, the magnitudes of T1 and T2 are the same, and the peak value of the triangular wave (peak voltage at the time of forming) is increased by about 0.1 V step, for example.

  The forming process is completed by inserting a voltage that does not cause local destruction or deformation of the conductive thin film 4 between the forming pulses, for example, by measuring a device current by inserting a pulse voltage of about 0.1V. Do. Here, the resistance value is obtained from the measured element current. For example, when the resistance is 1000 times or more of the resistance before the forming process, the forming is finished.

  In this state, the electron generation efficiency is not so high. Therefore, in order to increase the electron emission efficiency, it is desirable to perform a process called activation on the element.

  This treatment is performed by repeatedly applying a pulse voltage to the device electrode from the outside through the XY wiring under an appropriate vacuum degree in which an organic compound exists. Then, a gas containing carbon atoms is introduced, and carbon or a carbon compound derived therefrom is deposited as a carbon film in the vicinity of the crack.

In this step, p-tolunitrile was used as a carbon source, introduced into the vacuum space through a slow leak valve, and maintained at 1.3 × 10 ⁻⁴ Pa. The pressure of the p-tolunitrile to be introduced is slightly affected by the shape of the vacuum device, the members used in the vacuum device, and the like, but about 1 × 10 ⁻⁵ Pa to 1 × 10 ⁻² Pa is preferable.

  FIGS. 12A and 12B show a preferred example of voltage application used in the activation process. The maximum voltage value to be applied is appropriately selected within a range of 10 to 20V.

  In FIG. 12A, T1 indicates the pulse width of the voltage waveform, and T2 indicates the pulse interval. The absolute value and pulse width of the positive voltage and the negative voltage are set to be equal. On the other hand, in FIG. 12B, T1 indicates the pulse width of the positive voltage waveform, T1 ′ indicates the pulse width of the negative voltage waveform, and T2 indicates the pulse interval. The absolute values of the positive voltage and the negative voltage are equal and T1> T1 ′ is set. Any voltage application may be performed.

  At this time, the voltage applied to the device electrode 3 is positive, and the device current If flows in the direction from the device electrode 3 to the device electrode 2 is positive. About 60 minutes after applying the voltage, when the emission current Ie reached almost saturation, the energization was stopped, the slow leak valve was closed, and the activation process was completed.

  According to the manufacturing method of the present embodiment described above, since a plurality of ink jet devices 109 and 110 can be used to simultaneously apply droplets between the electrodes of a plurality of element electrode pairs, high throughput can be realized. Can do.

Further, since the ink jet device 109 having excellent performance is used for the element electrode pair arranged in the vicinity of the fixed position of the spacer, the electron emission portion in the region can be manufactured with high positional accuracy. As a result, the influence of the charging of the spacer can be minimized, and distortion of the display image can be suppressed.

  In addition, since the high-performance ink jet device 109 is used in a region where high positional accuracy is required, and the ink jet device 110 having poor performance is used in other regions, the cost of the electron source substrate manufacturing apparatus, and the electron source The manufacturing cost of the substrate can be reduced. That is, both low cost and high throughput can be achieved. In particular, in the present embodiment, since the number of nozzles of the high-performance inkjet device 109 is set to the minimum necessary number, the cost can be further reduced.

  In addition, since different types of ink jet devices 109 and 110 are fixed to one unit in which the heads are connected to each other, characteristics such as an element that requires positional accuracy and an element that does not require much positional accuracy are different. The electron-emitting devices can be manufactured in a lump.

  In addition, since the liquid droplets are applied while the unit and the substrate are moved relative to each other along the spacer arrangement direction, it is possible to manufacture electron-emitting devices having different characteristics with high throughput with extremely simple control. it can.

  In the above-described reference embodiment, the number of nozzles of the inkjet device 109 is set to four nozzles. However, by setting the number of nozzles larger than this, an inkjet with good performance up to a region farther from the spacer than the first and second adjacent rows. You may perform droplet application with an apparatus. Conversely, the number of nozzles may be set to be less than 4 nozzles, and for example, an ink jet device having good performance only in the first adjacent row may be used.

  Further, the number of nozzles of the inkjet device 110 is not limited to 20, and the number of inkjet devices to be combined is not limited to three. By increasing the number of nozzles and the number of ink jet devices, the throughput can be further improved.

(Second reference form)
Next, a second reference embodiment of the present invention will be described with reference to FIG.

  In this reference embodiment, an ink jet apparatus having a nozzle arrangement different from that for the other electrode pairs is used for the element electrode pairs arranged in the vicinity of the fixed position of the spacer. Since other configurations and operations are the same as those in the first reference embodiment, a detailed description of the same components will be omitted.

  As described above, the emitted electrons from the electron-emitting devices in the first and second adjacent rows in the vicinity of the spacer are bent by the influence of the spacer charging. The bending direction is a direction approaching the spacer, and it is known that the amount of change is larger in the first adjacent row than in the second adjacent row. Accordingly, the distortion of the display image can be eliminated by adjusting the positions of the electron-emitting devices in the first and second adjacent rows in advance in consideration of the amount of change in the electron trajectory due to the spacer charging.

In the present embodiment, the nozzle arrangement of the ink jet device 109 used for the pair of element electrodes (existing in the row indicated by A in the drawing) arranged near the fixed position of the spacer is set as follows. That is, as shown in FIG. 13, the nozzle interval d1 between the two nozzles 111 and 111 in the center for applying droplets to the device electrode pairs in the first adjacent row and the droplet application to the device electrode pairs in the first adjacent row. The nozzle interval d2 between the nozzle 111 for performing droplets and the nozzle 111 for applying droplets to the element electrode pairs in the second adjacent row is set to satisfy the relationship of d1> d2. In other words, the plurality of nozzles 111 of the ink jet device 109 are non-uniformly arranged so that the nozzle intervals are different depending on the position where the electron emission portion is to be formed.

  On the other hand, the inkjet apparatus 110 is the same as that of the first reference embodiment, and the nozzle interval d3 is uniform (although there is variation in processing accuracy). In addition, it is preferable to use an ink jet device with excellent performance such as landing accuracy and discharge amount accuracy as the ink jet device 109, and it is sufficient to use an ink jet device 110 with inferior performance.

  Here, d1 is set to 205 μm, d2 is set to 145 μm, and d3 is set to 205 μm. When the conductive thin film 4 was formed using the ink jet devices 109 and 110 as in the first reference embodiment, the X-direction wiring 115 provided with the spacers and the electron emitting portions in the first adjacent row were formed. L1 is 170 μm, and the distance L2 between the X-direction wiring adjacent to the X-direction wiring 115 and the center of the electron emitting portion of the second adjacent row is 140 μm, and the positional relationship is L1> L2. An electron-emitting device could be formed. The distance L3 was 170 μm.

  When the image display device using the electron source substrate thus fabricated was driven, the orbits were bent so that the electron beams from the electron emission portions of the first and second adjacent rows both approached the spacer. The intervals between the emission points of the respective electron beams were almost uniform, and a high-quality image without distortion could be displayed.

  According to the configuration of the present reference embodiment, the same operational effects as those of the first reference embodiment can be achieved. In addition, since the inkjet device 109 in which the nozzle intervals are non-uniformly arranged is used, electron emission portions in the vicinity of the spacer, which require a special positional relationship to correct the electron trajectory, can be collectively manufactured, Shortening and cost reduction can be realized.

(Embodiment)
Next, an embodiment of the present invention will be described with reference to FIGS.

  In the present embodiment, when applying droplets with an ink jet device, a different type of ink jet device is used for the element electrode pair disposed at the center of the screen than for the electrode pair disposed at the screen end. Use. Since other configurations and operations are the same as those in the first reference embodiment, a detailed description of the same components will be omitted.

  The sensitivity to the display image is not always the same everywhere on the screen. When an experiment as shown in FIG. 14 was performed, the sensitivity of the subject was highest in a region with a small angle of view (the center of the screen), and the sensitivity decreased as the field of view was widened (the edge of the screen). I understood. That is, it can be said that the subject cannot perceive the screen edge region even if the image quality is worse than the screen center region.

  Therefore, in this embodiment, as shown in FIG. 15, at least for the element electrode pair arranged in the center of the screen, the ink-conducting device 109 having excellent performance such as ejection amount accuracy and landing accuracy is used for conductivity. Liquid droplets were applied, and conductive droplets were applied to the element electrode pairs arranged at the edge of the screen by using the ink jet device 110 having a performance lower than that of the ink jet device 109.

  The three inkjet devices 110, 109, and 110 are separately attached, but are simultaneously driven so as to collectively produce electron emitting elements at the upper end portion of the screen, the center portion of the screen, and the lower end portion of the screen. Thereby, high throughput can be realized.

  Further, since the ink jet device 109 having excellent performance is used for the element electrode pair arranged in the center of the screen, the electron emission portion in the region can be manufactured with high positional accuracy. As a result, the image quality in a region where the sensitivity of the human eye is high can be particularly improved.

  Further, the electron source substrate could be produced without using many expensive ink jet devices which were high cost due to high accuracy like the ink jet device 109.

  In addition, it is possible to use a large number of nozzles at the same time by shortening the manufacturing procedure by manufacturing the electron-emitting device at locations where high-precision positional accuracy is required and locations where it is not using different types of inkjet devices. In addition, the cost could be reduced.

(Other embodiments)
In each of the above reference embodiments and embodiments, the device electrodes and wirings of the MTX substrate are produced using photolithography technology, but it is also preferred to produce them by screen printing instead. The process of forming other conductive thin films and electron emission portions is performed in the same manner as in the above reference embodiment and embodiment. As a result, the cost can be kept low compared with the thin film process, and the manufacturing yield is greatly improved.
(Reference example)

  Hereinafter, although one suitable reference example of the present invention is explained in detail, the present invention is not limited to these reference examples. Here, referring to the drawings used in each of the above-mentioned reference forms again, description will be made using the same reference numerals.

First, a 2.8 mm thick glass of PD-200 (manufactured by Asahi Glass Co., Ltd.) having a small alkali component is used as the insulating substrate 1, and further a SiO ₂ film 100 nm is applied and fired thereon as a sodium block layer. After thoroughly washing with an organic solvent or the like, it was dried at 120 ° C.

  Next, a titanium Ti film having a thickness of 5 nm is formed on the insulating substrate 1 as a subbing layer by sputtering, and a platinum Pt film having a thickness of 40 nm is formed thereon, a photoresist is applied, and patterning is performed by a series of photolithography methods including exposure, development, and etching. Then, the device electrodes 2 and 3 were formed (FIG. 5). Further, the Y-direction wiring 10 made of Au was formed by the same method (FIG. 6). At this time, the gap interval between the device electrodes 2 and 3 is 20 μm, the electrode width is 500 μm, the thickness is 50 nm (500 angstroms), the pitch between the devices is 1 mm, the width of the Y-direction wiring 10 is 300 μm, and the thickness is 50 nm. (500 angstroms).

  Subsequently, in order to insulate the upper and lower wirings, an interlayer insulating layer 6 was disposed using a vacuum film forming technique and a photolithography technique. Contact is made to the connection portion so as to cover the intersection of the X-direction wiring (upper wiring) 11 and the Y-direction wiring (lower wiring) 10 and to allow the X-direction wiring 11 and the element electrode 2 to be electrically connected. A hole was formed (FIG. 7).

  And the X direction wiring 11 which consists of Au connected with one element electrode 2 was formed using the vacuum film-forming technique and the photolithography technique (FIG. 8). The wiring width was 20 nm (200 angstroms), and the thickness was 500 nm (5000 angstroms).

  Next, the organic palladium-containing solution was applied drop by drop so as to straddle the device electrodes 2 and 3 using the ink jet devices 109 and 110. As the organic palladium-containing solution, a solution obtained by dissolving a palladium-proline complex in an aqueous solution composed of water and isopropyl alcohol (IPA) and adding some other additives is used.

  At this time, the inkjet device 109 having four nozzles 111 and the inkjet device 110 having 20 nozzles 112 were used. Further, with respect to the nozzles constituting the ink jet device 109, the nozzles constituting the ink jet device 110 using a high-accuracy head such that the droplets dropped therefrom are within ± 3 μm with respect to a predetermined position on the MTX substrate. With respect to, a head with relatively low accuracy is used so that the liquid droplets dropped from it are about ± 10 μm with respect to a predetermined position on the MTX substrate.

  When applying droplets, as shown in FIG. 9, the region 113 in the vicinity of the spacer is always applied with the droplets 8 using the inkjet device 109, and the inkjet device 110 is used for the other regions 114. By applying the droplets, the electron-emitting device in the vicinity of the spacer is manufactured with high positional accuracy.

Thereafter, a heat treatment was performed at 300 ° C. for 10 minutes to form a fine particle film made of palladium oxide (PdO) fine particles, thereby forming a conductive thin film 4 (FIG. 10). The amount of one droplet was controlled to 60 μm ³ .

  Next, an electron emission portion 5 was formed by applying a voltage between the element electrodes 2 and 3 and conducting the conductive thin film 4 with an energization treatment (energization forming).

  Using the electron source substrate thus manufactured, an envelope 90 is formed by a face plate 82, a support frame 86, a rear plate 81, and a spacer 91 as shown in FIG. Further, an image forming apparatus having a drive circuit for performing television display based on an NTSC television signal was manufactured.

  At that time, the position where the spacer 91 was installed was installed in the region 113 produced by the inkjet device 109 described above. As a result, the positions of the electron-emitting devices in the first and second adjacent rows in the vicinity of the spacer can be arranged with an accuracy of ± 6 μm with respect to the position of the spacer, and even if the bending of the beam due to the charging of the spacer is taken into consideration The strain could be reduced to such an extent that it could not be confirmed visually.

  The electron-emitting device manufactured as described above by the manufacturing method of this reference example not only showed good characteristics without any problems, but also can reduce the distortion of the image due to the charging of the spacers to the extent that it cannot be visually confirmed. It was possible to form a clear image.

  In addition, it is possible to use a large number of nozzles at the same time by manufacturing the electron-emitting device at locations where high-accuracy position accuracy is required and locations where it is not required, thereby simultaneously reducing the manufacturing procedure and cost. It was possible to achieve a reduction.

It is a schematic perspective view which shows the image display apparatus as an application example of an electron source board | substrate. It is a schematic diagram which shows the electron source substrate which concerns on the 1st reference form of this invention, and the inkjet apparatus used in order to produce it. It is a schematic diagram which shows the surface conduction type electron-emitting device which comprises the electron emission part of an electron source substrate. It is a schematic diagram explaining the droplet provision by an inkjet apparatus. It is a schematic diagram explaining the preparation process of an element electrode. It is a schematic diagram explaining the production process of Y direction wiring. It is a schematic diagram explaining the preparation process of an interlayer insulation layer. It is a schematic diagram explaining the manufacturing process of a X direction wiring. It is a schematic diagram explaining the relative movement of an inkjet apparatus unit and a board | substrate. It is a schematic diagram explaining the preparation process of an electroconductive thin film. It is explanatory drawing which shows the voltage waveform in a forming process. It is explanatory drawing which shows the voltage waveform in an activation process. It is a schematic diagram which shows the electron source substrate which concerns on the 2nd reference form of this invention, and the inkjet apparatus used in order to produce it. It is a schematic diagram explaining the sensitivity with respect to a display image. It is a schematic diagram which shows the electron source substrate which concerns on embodiment of this invention, and the inkjet apparatus used in order to produce it. It is a figure which shows the typical element structure of a surface conduction electron-emitting element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2, 3 Element electrode 4 Conductive thin film 5 Electron emission part 6 Interlayer insulation layer 8 Droplet 10 Y direction wiring 11 X direction wiring 80 Electron source substrate 81 Rear plate 82 Face plate 83 Glass substrate 84 Fluorescent film 85 Metal back 86 Support frame 87 Electron-emitting device 88 X-direction wiring 89 Y-direction wiring 90 Envelope 91 Spacer 109, 110 Inkjet device 111, 112 Nozzle 113 Region near spacer fixed position 114 Region other than region near spacer fixed position 115 Spacer X direction wiring Hv high voltage terminal

Claims (2)

A method for manufacturing an electron source substrate used in an image display device,
Forming a plurality of electrode pairs on a substrate;
Forming a conductive film by applying a droplet containing a conductive substance between each electrode of a plurality of electrode pairs using an inkjet device having a plurality of heads having a plurality of nozzles; and
Forming an electron emission portion in the conductive film,
The application of the droplet is used for the first head used for the electrode pair on the substrate located at the edge of the screen and the electrode pair on the substrate located at least in the center of the screen. A method of manufacturing an electron source substrate, wherein the second head having higher landing accuracy than that of the first head is driven simultaneously . A method for manufacturing an electron source substrate used in an image display device,
Forming a plurality of electrode pairs on a substrate;
Forming a conductive film by applying droplets containing a conductive substance between the electrodes of a plurality of electrode pairs using an inkjet apparatus having a plurality of heads having a plurality of nozzles; and
Forming an electron emission portion in the conductive film,
The application of the droplet is used for the first head used for the electrode pair on the substrate located at the edge of the screen and the electrode pair on the substrate located at least in the center of the screen. A method of manufacturing an electron source substrate, wherein the second head having a higher discharge amount accuracy than that of the first head is simultaneously driven .

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