JPH1050207A - Manufacture of image display element substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a complicated three-dimensional laminated shape easily by simplifying a production process. SOLUTION: An under wiring, an interlayer insulation layer, an element electrode, an upper wiring, and an electron emission portion forming thin film are formed on an insulating substrate 21 so as to form an electron source substrate, on which forming processing is conducted so as to form the electron emission portion. In such a manufacturing method for an image display element substrate, at least one of the lower wiring 25, the interlayer insulation layer, the element electrode, the upper wiring, and the electron emission portion forming thin film is formed by a filling method. Comparing with a conventional manufacturing method in which all of these are manufactured by the combination of a deposition method and a photolithography method, a vacuum process is eliminated or is reduced so that the production process is simplified. Also, a complicated three-dimensional shape can be easily manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device using a surface conduction electron-emitting device, and more particularly to a method for manufacturing an element substrate.

[0002]

2. Description of the Related Art In recent years, flat panel display devices using liquid crystal have been
Although it has become widespread in place of the RT, there is a problem that it is not a self-luminous type and it must have a backlight or the like, and development of a self-luminous type image display device has been desired. Against this background, an image display device has been proposed, which is a display device that combines an electron source having a large number of surface conduction electron-emitting devices and a phosphor that emits visible light by electrons emitted from the electron source. This image display device has recently been receiving particular attention because it is a self-luminous display device that can be relatively easily manufactured even on a large screen and has excellent display quality.

The above-mentioned electron source is disclosed in, for example,
There is a technical disclosure in -176265. As shown, the electron source is composed of an insulating substrate,
It has a lower wiring (X-direction wiring), an interlayer insulating layer, an element electrode, an upper wiring (Y-direction wiring), a thin film including an electron emitting portion, and the like. Hereinafter, a method for manufacturing an electron source described in this publication will be described with reference to the process chart shown in FIG.

(Step (a)) A 50 .mu.m thick Cr, 6000 .mu.m thick Au film is formed on a substrate 11 having a 0.5 .mu.m thick silicon oxide film formed on a cleaned blue sheet glass by a sputtering method. Are sequentially laminated, and then a photoresist (“AZ137 manufactured by Hoechst Co., Ltd.”) is used.
0 ") by spin coating with a spinner and baking, exposing and developing a photomask image to form a resist pattern for the lower wiring, and wet-etching the Au / Cr deposition layer to form a lower wiring 12 having a desired shape. Form.

[Step (b)] Next, an interlayer insulating layer 13 made of a silicon oxide film having a thickness of 1.0 μm is deposited by RF sputtering.

(Step (c)) A photoresist pattern for forming a contact hole 14 is formed in the silicon oxide film deposited in the step (b), and the interlayer insulating layer 13 is etched using the photoresist pattern as a mask to form the contact hole 14. Form. Etching is CF
RIE (Reactive Ion Etching) using ₄ and H ₂ gas
According to the law.

[Step (d)] Thereafter, the device electrodes 15, 16 and the gap L1 between the device electrodes are formed.
A pattern to be formed was formed of a photoresist (“RD-2000N-41” manufactured by Hitachi Chemical Co., Ltd.), and a Ti film having a thickness of 50 ° and a Ni film having a thickness of 1000 ° were sequentially deposited by a vacuum deposition method. After dissolving the photoresist pattern with an organic solvent, unnecessary portions of the Ni / Ti deposited film were lifted off to form device electrodes 15 and 16. The element electrode interval L1 is 2 μ
m, and the width of the device electrode was 220 μm.

-Step (e)-After forming a photoresist pattern of the upper wiring 17 on the device electrodes 15 and 16, a Ti film having a thickness of 50 ° and an Au film having a thickness of 5000 ° are sequentially deposited by a vacuum evaporation method, and lift-off is performed. By removing unnecessary portions, the upper wiring 17 having a desired shape was formed.

(Step (f)) A mask (electrode gap L between the elements)
1 and a mask having an opening in the vicinity thereof).
The Cr film 18 is deposited and patterned by vacuum evaporation, and an organic Pd ("cpp42" manufactured by Okuno Pharmaceutical Co., Ltd.) is formed thereon.
30 ") by spin coating with a spinner, about 10 at 300 ° C.
For 2 minutes. The electron emitting portion forming thin film 19 composed of fine particles of Pd as the main element thus formed has a thickness of 100 ° and a sheet resistance of 5 × 10 5.
It was ⁴ Ω / □. In addition, the fine particle film described here is a film in which a plurality of fine particles are aggregated, and as a fine structure,
The film refers not only to the state in which the fine particles are individually dispersed and arranged, but also to a film in a state in which the fine particles are adjacent to each other or overlap each other (including an island shape). To tell.

Step (g) The Cr film 18 and the fired thin film 19 for forming the electron emission portion 19 were etched with an acid etchant to form a desired pattern.

-Step (h)-A pattern is formed such that a resist is applied to portions other than the contact hole 14, and a 50 ° -thick T
i and 5000 Å thick Au were sequentially deposited. Unnecessary portions were removed by lift-off to fill the contact holes 14.

Through the above steps, the lower wiring 12, the interlayer insulating layer 13, the device electrodes 15, 16, the upper wiring 17, the electron emitting portion forming thin film 19, etc. were formed on the insulating substrate 11. The substrate thus manufactured is referred to as an electron source substrate that has not been subjected to the forming process.

Next, an electron emission portion is formed on the electron source substrate by an electric heating process called forming to produce an image display element substrate. That is, by applying a voltage between the device electrodes 15 and 16,
9 and the resulting thin film 19
Is locally destroyed, deformed or altered to form an electron emitting portion in an electrically high resistance state, thereby obtaining an electron emitting function.

[0014]

However, in the above-described method, since the vapor deposition method and the photolithography method are combined, there are problems that it is difficult to increase the area and that the manufacturing cost and time are increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to simplify the process and to easily produce a complicated three-dimensional laminated shape. It is an object of the present invention to provide a method for manufacturing an image display element substrate.

[0016]

In order to achieve the above object, the present invention forms a lower wiring, an interlayer insulating layer, an element electrode, an upper wiring, and a thin film for forming an electron emitting portion on an insulating substrate. In the method of manufacturing an image display element substrate in which an electron emission portion is formed by performing a forming process on the electron source substrate manufactured as described above, at least one of the lower wiring, the interlayer insulating layer, the element electrode, and the upper wiring One is formed by a filling method. The method of forming the electron-emitting portion by the forming process is the same as the conventional method.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

(Formation of Lower Wiring) First, as shown in FIG. 2A, a photosensitive resin layer 22 is provided on a substrate 21. Specifically, a 0.5 μm thick
A 50 μm-thick dry film resist (“Nichigo Alfo NEF150” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was laminated by heat lamination on a substrate formed by forming a silicon oxide film having a thickness of m by sputtering. Next, as shown in FIG. 2B, the photosensitive resin layer 22 on the substrate 21 is exposed through a mask 23 having a desired pattern. Here, a parallel light printer using an ultra-high pressure mercury lamp as a light source is used. The exposure conditions are an intensity of 3200 μW / cm ² at a wavelength of 265 nm and an irradiation amount of 120 mJ / cm ² . Thereafter, as shown in FIG. 2C, development is performed to remove unexposed portions of the photosensitive resin layer 22. Here, a 1% sodium carbonate aqueous solution is used,
Spray development was performed at room temperature. Through the above steps, a template having a desired pattern was obtained.

Next, as shown in FIG. 2D, a template 24 of the photosensitive resin layer 22 is filled with an electrode forming paste 24. Specifically, while using a paste for forming an Ag electrode, the pattern 24 is moved obliquely across the pattern while the squeegee for screen printing is in contact with the template to fill the paste 24, and the excess paste that has protruded is scraped. I took it. After filling, dried at 150 ° C for 20 minutes,
This filling and drying process was repeated three times.

Then, as shown in FIG. 2E, the template of the photosensitive resin layer 22 is removed and firing is performed to form the lower wiring 25. Specifically, the substrate was immersed in a 3 wt% aqueous solution of anhydrous sodium carbonate kept at 40 ° C. to remove the template of the dry film resist. The paste was successfully peeled without peeling. After the template was peeled off, it was baked at a peak temperature of 580 ° C. This makes the height 37 ± 3μm
Good electrode wiring with high uniformity was obtained. Through the above steps, the lower wiring 25 was formed.

(Formation of Interlayer Insulating Layer) Subsequently, FIG.
As shown in FIG. 5, a photosensitive resin layer 26 is formed on the substrate 21 and the photosensitive resin layer 26 is
Exposure through 7 Specifically, after a 50 μm-thick dry film resist (“Nichigo Alfo NEF150” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) is laminated on the substrate 21 having the lower wiring 25 by a heat lamination method, an ultra-high pressure mercury lamp is used. Exposure was performed using a parallel light printer as a light source. The exposure conditions are an intensity of 3200 μW / cm ² at a wavelength of 265 nm and an irradiation amount of 120 mJ / cm ² . Thereafter, as shown in FIG. 3B, development is performed to remove the unexposed portions of the photosensitive resin layer 26. Here, spray development was performed at room temperature using a 1% aqueous sodium carbonate solution. Through the above steps, a template having a desired pattern was obtained.

Next, as shown in FIG. 3C, a template of the photosensitive resin layer 26 is filled with a glass paste 28. At the time of filling, while the squeegee for screen printing was in contact with the template, the pattern was moved obliquely across the pattern to fill the paste, and the excess paste that had overflowed was scraped off. After filling, at 150 ° C 2
After drying for 0 minutes, this filling and drying process was repeated 5 times.

Then, as shown in FIG. 3D, the template of the photosensitive resin layer 26 is removed, and the photosensitive resin layer 26 is baked to form an insulating layer 29.
To form Specifically, the substrate was immersed in a 3 wt% aqueous solution of anhydrous sodium carbonate kept at 40 ° C. to remove the template of the dry film resist. The paste was successfully peeled without peeling. After the template was peeled off, it was fired at a peak temperature of 550 ° C. This makes the height 113 ± 5
A good insulating layer 29 having a high uniformity of μm was obtained.

(Formation of Device Electrode) As shown in FIG. 4A, an empty wall of the insulating layer 29 previously formed is filled with an electrode forming paste to form an access electrode 30 to the upper part. deep. Specifically, while using a paste for forming an Au electrode, a screen printing squeegee is moved obliquely across the pattern while the squeegee for screen printing is in contact with the insulating layer 29, and the paste is filled. I took it. After filling, it was dried at 150 ° C. for 20 minutes. Next, firing was performed at a peak temperature of 580 ° C.

Next, as shown in FIG.
9, a photosensitive resin layer 31 is formed, and the photosensitive resin layer 31 is exposed through a mask 32 having a desired pattern. Specifically, a 25 μm-thick dry film resist (“Nichigo Alfo N” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) is formed on the insulating layer 29.
EF150 ") is laminated one layer by a heating lamination method,
Exposure was performed using a parallel light printer using an ultra-high pressure mercury lamp as a light source. Exposure conditions are 3200μ intensity at a wavelength of 265nm.
W / cm ² , irradiation amount 120 mJ / cm ² . Thereafter, as shown in FIG. 4C, development is performed to remove unexposed portions of the photosensitive resin layer 31. Here, spray development was performed at room temperature using a 1% aqueous sodium carbonate solution.
Through the above steps, a template having a desired pattern was obtained.

Next, as shown in FIG. 4D, a template of the photosensitive resin layer 31 is filled with an electrode forming paste 33. Specifically, while using a paste for forming an Au electrode, a screen printing squeegee is moved obliquely across the pattern while the squeegee is in contact with the template, and the paste is filled, and excess paste that has overflowed is scraped off. I did it. After filling, it was dried at 150 ° C. for 20 minutes.

Then, as shown in FIG. 4E, the template of the photosensitive resin layer 31 is removed, and the photosensitive resin layer 31 is baked to form the element electrode 3.
4 is formed. Specifically, when the sample was immersed in an aqueous solution of 3% by weight of anhydrous sodium carbonate kept at 40 ° C. and the template of the dry film resist was peeled off, the paste could be peeled off without peeling off. After exfoliating the template, baking was performed at a peak temperature of 580 ° C. As a result, a favorable electrode wiring having a high uniformity of 7 ± 0.5 μm was obtained. The element electrode 33 was formed by the above steps.

(Formation of Upper Wiring) First, as shown in FIG. 5A, a photosensitive resin layer 35 is formed on a substrate so as to cover the element electrode 34, and the photosensitive resin layer 35 is formed in a desired pattern. Is exposed through the mask 36 of FIG. Specifically, a 50 μm-thick dry film resist (“Nichigo Alfo NEF150” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) is laminated on a substrate by one layer by a heating lamination method, and then a parallel light printer using an ultra-high pressure mercury lamp as a light source. Exposure was performed using Exposure conditions are wavelength 265 nm, intensity 3200 μW / cm ² , dose 12
0 mJ / cm ² . Thereafter, as shown in FIG. 5B, development is performed to remove unexposed portions of the photosensitive resin layer 35. Here, spray development was performed at room temperature using a 1% aqueous sodium carbonate solution. By the above method, a template having a desired pattern was obtained.

Next, as shown in FIG. 5C, the template of the photosensitive resin layer 35 is filled with an electrode forming paste 37. Specifically, while using a glass paste for forming an Au electrode, the pattern is moved diagonally across the pattern while the squeegee for screen printing is in contact with the template, and the paste is filled, and the excess paste that has protruded is scraped. This filling and drying process was repeated 5 times. After filling, it was dried at 150 ° C. for 20 minutes.

Next, as shown in FIG. 5D, the template of the photosensitive resin layer 35 is removed and baked to form the upper wiring 38. Specifically, when the sample was immersed in an aqueous solution of 3% by weight of anhydrous sodium carbonate kept at 40 ° C. and the template of the dry film resist was peeled off, the paste could be peeled off without peeling off. After removing the template,
Baking was performed at a peak temperature of 550 ° C. This makes the height 7 ±
Good electrode wiring having a high uniformity of 0.5 μm was obtained.
Through the above steps, the upper wiring 38 was formed.

Next, an organic solvent containing an organic palladium compound ("Catapaste CCP" manufactured by Okuno Pharmaceutical Co., Ltd.) is printed at a desired position by a screen printing method, and then left for 15 minutes and then at about 200 ° C. for 20 minutes. By firing, a thin film for forming an electron-emitting portion formed of a fine particle layer made of Pb was formed. A substrate for an electron source was manufactured by the above procedure, and an element substrate for image display was manufactured using the substrate. As a result, good electron emission characteristics were obtained.

In the process described above, the photosensitive resin layer may be formed by coating a liquid resist. As the coating method, there are a screen printing method, a spin coating method, a fusion method, a roll coating method, a reverse coating method, a spray method, a dipping method and the like.

It is not necessary to carry out all of the steps only by the filling method. Some of the steps are carried out by a combination of a vapor deposition method and a photolithography method, a photolithography method using a photosensitive paste, a sand blast method, a printing method, or the like. It is also possible to combine with the filling method.

[0034]

As described above, according to the present invention, a lower wiring, an interlayer insulating layer, an element electrode, an upper wiring, and a thin film for forming an electron-emitting portion are formed on an insulating substrate, and manufactured in this manner. In a method for manufacturing an image display element substrate in which an electron emission portion is formed by performing a forming process on an electron source substrate, at least one of the lower wiring, the interlayer insulating layer, the element electrode, and the upper wiring is formed by a filling method. By doing so, the vacuum process is eliminated or reduced as compared with the conventional case where all of them are manufactured by a combination of the vapor deposition method and the photolithography method, so that the process can be simplified and the complicated 3 A two-dimensional laminated shape can also be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a process chart showing a conventional method for manufacturing an electron source.

FIG. 2 is a process chart showing a procedure for forming a lower wiring by a filling method.

FIG. 3 is a process chart showing a procedure for forming an interlayer insulating layer by a filling method.

FIG. 4 is a process chart showing a procedure for forming an element electrode by a filling method.

FIG. 5 is a process chart showing a procedure for forming an upper wiring by a filling method.

[Explanation of symbols]

 Reference Signs List 21 substrate 22 photosensitive resin layer 23 mask 24 electrode forming paste 25 lower wiring 26 photosensitive resin layer 27 mask 28 glass paste 29 insulating layer 30 access electrode 31 photosensitive resin layer 32 mask 33 electrode forming paste 34 element electrode 35 photosensitive Resin layer 36 Mask 37 Electrode forming paste 38 Upper wiring

Claims (1)

[Claims] 1. A lower wiring, an interlayer insulating layer, an element electrode, an upper wiring, and a thin film for forming an electron emitting portion are formed on an insulating substrate, and a forming process is performed on the electron source substrate thus manufactured. A method for manufacturing an image display element substrate in which an electron emission portion is formed by forming at least one of the lower wiring, an interlayer insulating layer, an element electrode, and an upper wiring by a filling method. Substrate manufacturing method.