JP2001155626A - Method for producing display substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a display substrate which can avoid a problem caused by the bleeding of a printing paste or a defect of a plate making. SOLUTION: A printing process SB3 applies a useless thick film silver paste (a useless pattern) on a masking in a print-prohibition area without a direct application on a film forming surface even if a defect of a plate making for forming a row direction wiring is present or the thick film silver paste spreads on the film forming surface by applying the thick film silver paste to the film forming surface in a state that the print-prohibition area is covered with the masking, and a burning process SB4 removes the useless thick film silver paste together with the masking from am upside of the film forming surface. Accordingly, the thick film silver of the useless pattern is prevented from depositing and furthermore fixing to the print-prohibition area. Meanwhile, in a outside of the print-prohibition area, even of an excess portion is caused by the bleeding to the outside of the printing pattern, no problem in function of the display substrate occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a display substrate, and more particularly, to an improvement in a film forming technique using thick film screen printing.

[0002]

2. Description of the Related Art Various types of flat panel display devices have been known. For example, a fluorescent display tube (VFD) that excites and emits a phosphor with electrons generated from a hot cathode, and an electric field electron that excites and emits a phosphor with electrons generated by field emission. Field Emission Displ
ay: FED), or a plasma display panel (PDP) or the like, which uses plasma emission generated by gas discharge as it is or excites and emits a phosphor with the plasma to display. is there.

[0003] The flat display device as described above is, for example,
There is provided an airtight container formed by sealing a pair of display substrates arranged in parallel with each other via a spacer. Each of the pair of display substrates has a plurality of at least two types of electrodes or wirings, an electron beam, and the like, in order to selectively emit a desired one of a plurality of light emitting sections provided in the display device. Phosphors and the like for converting plasma into visible light are provided in various patterns according to the type of display device.

[0004]

By the way, in the above display device, part or all of the electrodes, wirings, phosphors, etc. on the display substrate are formed by a thick film screen printing method. . However, in general,
In thick film screen printing, it is difficult to avoid bleeding or spreading of the printing paste during printing. Therefore, when trying to form a fine pattern, the adjacent thick films come into contact with each other or overlap with each other, so that there is a problem that short-circuiting between conductors, color mixing or deterioration of the phosphor may occur.
Such defects due to unnecessary contact and overlapping of thick films also occur when printing paste is applied to unnecessary portions due to defects such as pinholes and missing patterns in screen plate making. obtain. Further, these problems become more pronounced as the film formation surface becomes larger and the print pattern becomes finer.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a display substrate capable of suppressing a problem caused by bleeding of a printing paste or a defect in plate making. It is in.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is to manufacture a display substrate by forming a plurality of types of films including a thick film pattern on a film forming surface of a substrate. (A) a masking step of covering a predetermined print-inhibited area with a predetermined masking material on which a printing paste for forming the thick film pattern of the film forming surface should not adhere. (B) a printing step of screen-printing the printing paste in a predetermined pattern on the film forming surface on which the masking has been performed, and (c)
And a removing step of removing the masking material after the printing step.

[0007]

According to this method, the printing paste is applied to the film forming surface in a state where the printing prohibited area is covered with the masking material, so that there is a defect in the plate making or that the printing paste is on the film forming surface. Even in the case of bleeding, unnecessary printing paste is not directly applied to the film forming surface but applied to the masking material in the print prohibited area, and is removed from the film forming surface together with the masking material in the removing step. You. For this reason, it is possible to suppress the useless printing paste from adhering to the print-inhibited area and extending therefrom. On the other hand, outside the print prohibited area, bleeding or adhesion of print paste due to plate making defects may occur outside the print pattern, but there is no inconvenience in the function of the display substrate. In other words, the print-prohibited area is set in a range in which the function of the display substrate is impaired when unnecessary print paste is attached. Therefore, when manufacturing the display substrate, the occurrence of defects due to the bleeding of the printing paste and the defects of the plate making is suppressed.

[0008]

In another preferred embodiment, the masking material is PMMA (polymethyl methacrylate), PMA
It is a photosensitive resin such as MIPK (polymethylisopropenyl ketone), polyvinyl alcohol-ammonium dichromate, or polyvinylpyrrolidone-diazidostilbene. With this configuration, the print-inhibited area can be covered with the masking material by the exposure and development processes, so that the masking pattern can be formed with high accuracy. The above-mentioned masking material is used after being formed into a film or dissolved and dispersed in a solvent. In the latter case, for example, an aqueous solvent such as water and an alkaline aqueous solution, or an organic solvent such as a glycol ether such as toluene, methyl cellosolve, butyl cellosolob, or methyl carbitol, and a glycol ester such as cellosolve acetate or butyl carbitol acetate. Is used.

Preferably, the masking material is aluminum (Al), nickel (Ni), iron (Fe), copper (C
u), a metal material such as zinc (Zn), chromium (Cr), or silver (Ag). With this configuration, the printing prohibited area can be covered with the masking material by the exposure, development, and etching processes, so that the masking pattern can be formed with high accuracy.

Preferably, (a-2) the masking step uses an organic compound as the masking material, and (c-2) the removing step comprises heating the print paste. This is a heat treatment step of burning off the masking material while forming a thick film. With this configuration, the masking material is burned off during the heat treatment for forming a thick film from the printing paste, so that the number of steps for removing the masking material and the process are not complicated. On the other hand, the printing paste attached on the masking is not completely burned out because it contains an inorganic substance or a metal, but when gasified in the process of burning out the masking material, the steam causes the steam to be discharged in the heat treatment. Are transported together, or are transported to a position outside the print-inhibited area on the film-forming surface to which it has adhered. Therefore, it is not necessary to particularly perform a process for removing the print paste attached to the print prohibited area. In addition, as the organic compound, the above-described photosensitive resin and resin material are suitably used.

Preferably, when the removing step is a heat treatment step as described above, the masking material is a cellulose resin such as methyl cellulose or ethyl cellulose, or methyl acrylate, butyl acrylate, acrylonitrile or the like. Acrylic resin. In this way, the masking material can be decomposed and burned at a lower temperature than when the photosensitive resin is used as the masking material.

Preferably, when the removing step is a heat treatment step as described above, the masking material is
An organic compound that can be burned off without generating residues such as metal elements and compounds thereof when decomposed by heating.

Preferably, in the case where the removal step is a heat treatment step as described above, (a-3) the masking step is performed in an area where the print paste must not adhere to the function of the display substrate. Only the masking material is provided. In this way, the print paste adhering to a region that is out of the print pattern but has no functional problem is not carried by the vapor of the masking material in the removal process, and is fixed to the print position as it is. Can be For this reason, the print paste adhered to the unhindered area cannot be carried to the print prohibited area during the heat treatment, and the thick film generated from the print paste is further suppressed from sticking to the print prohibited area. Is done.

Preferably, the masking material comprises:
The contact angle with the printing paste is larger than that of the film forming surface. In this case, since the print paste is difficult to spread on the masking material having a large contact angle with the print paste, the enlargement of the pattern width dimension due to the bleeding of the print paste or the dripping of the paste is appropriately suppressed. . Therefore, a thick film pattern with higher definition can be formed.

Preferably, the masking step includes the step of applying the masking material to a thick film screen printing method, attaching a film or sheet, photolithography method, vacuum deposition, sputtering, electrolytic or electroless plating, or electroless plating. It is provided on the film forming surface by casting or the like. That is, in the masking step, an appropriate method can be adopted according to the required pattern accuracy and dimensions, the type of the masking material, and the like.

Preferably, two or more types of the thick film patterns are provided, and a plurality of the two or more types of printing pastes for forming the two or more types of thick film patterns are formed on the film forming surface. If there is a region on each of which is not adhered, the masking step and the removing step are respectively performed when forming a thick film from the two or more kinds of printing pastes. In this way, since all the printing paste is applied avoiding the area on the film forming surface where the printing paste should not adhere, that is, the printing prohibited area, the problem of the display substrate due to the unnecessary adhesion of the printing paste is further suppressed. Is done. For example, in the case of a phosphor substrate on which a plurality of types of phosphor layers are coated on the film forming surface, it is necessary to prevent color mixing of the phosphors. It is necessary to perform masking at the position where the is applied, thereby suppressing unnecessary adhesion. In the case where a plurality of types of conductor wirings, electrodes, and the like are formed by lamination, it is preferable that each of the portions is masked at a portion necessary for preventing short circuit.

[0017]

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

FIG. 1 shows an FED 10 in which a method of manufacturing a display substrate according to an embodiment of the present invention is applied to the manufacturing process.
FIG. 2 is a perspective view showing the configuration of FIG. In the figure, the FED 10 has substantially flat surfaces 12, 14 respectively.
A front plate 16 and a back plate 18 having the same size and shape are arranged parallel to each other at a predetermined interval so as to face each other, and a spacer 22 is arranged between them. The front plate 16, the back plate 18, and the spacer 22 are hermetically sealed with each other, and constitute an airtight container that is an envelope of the FED 10. For example, 6.7 × 10 ^-5 (Pa) [5 × 10 ^-7
(Torr)].

The front plate 16 and the rear plate 18 are made of a glass having a uniform thickness of, for example, about 1 to 2 (mm) and a light-transmitting softening point of about 600 (° C.). For example, it is made of soda lime glass or the like. The spacer 22 has, for example, a rectangular frame shape or a lattice shape having the same outer dimensions as the front plate 16 and the back plate 18. This spacer 22 is, for example, 4
An insulating glass (not shown) made of borosilicate glass or the like having a softening point of about 600 (° C.) is formed on the surface of a material such as a rectangular frame or a grid having a uniform thickness of about 2 to 5 (mm) made of 26 alloy. Layer
It is configured to have a thickness of about 10 (μm) by electrodeposition or the like. For this reason, the distance between the front plate 16 and the rear plate 18, that is, the height dimension of the airtight space is, for example, about 2 to 5 (mm).

A plurality of stripe-shaped transparent anodes 24 made of, for example, ITO (Indium Tin Oxide) and having a width of about 0.1 to 0.5 (mm) are formed on one surface 12 of the front plate 16. For example, they are arranged side by side in one direction with a constant center interval of about 0.1 to 0.5 (mm). The surface of each of the plurality of anodes 24 has R
The phosphor layers 26 corresponding to any one of the three emission colors (red), G (green), and B (blue) are repeatedly arranged in the direction orthogonal to one direction, for example, in the order of R, G, and B. And anode 2
It is provided in the form of a stripe or a matrix with the same width dimension as that of No. 4. The anode 24 is formed to a thickness of, for example, about 1 (μm) by a thin film method such as sputtering, and has a relatively high conductivity with a sheet resistance of about 10 (Ω / □) or less. ing. The phosphor layer 26 is made of a material that emits visible light by an electron beam such as ZnO: Zn, ZnS: Ag + In ₂ O ₃ , and is, for example, a thick film screen printing method. 10-20 (μ
m), the area resistivity is 50
Conductivity of about 0 (Ω / cm ² ) or less is provided. Also,
In the three types of phosphor layers 26, there is no color mixing caused by mixing other phosphors.

A black matrix (mask) made of glass containing, for example, a black pigment is provided on the remaining surface of the one surface 12 of the front plate 16 where the phosphor layer 26 is not provided.
Are provided with a thickness of about 10 to 20 (μm), and the surface of the phosphor layer 26 and the black matrix 28 are provided.
Is covered with a metal back 30 having a thickness of about 100 to 200 (nm) provided on the entire surface 12 according to the surface shapes of the phosphor layer 26 and the black matrix 28. The black matrix 28 is provided by, for example, a thick film screen printing method. When the phosphor layers 26 are provided in a stripe shape, the phosphor layers 26 are arranged in a stripe shape passing therebetween. When they are provided in a shape, they are formed in a lattice shape. Further, the metal back 30 is provided, for example, by vapor deposition of an aluminum thin film, and has a relatively smooth surface and is formed in a thin film having a thickness such that electrons can easily pass therethrough.

On the other hand, on one surface 14 of the back plate 18,
A plurality of column-direction (Y-direction) wirings 32 and row-direction (X-direction) wirings 34 extending in two directions (the column direction, ie, the Y direction and the row direction, ie, the X direction) perpendicular to each other form the interlayer insulating layer 36. It is provided in layers. The column wirings 32 are provided in parallel with the anode 24 on the front plate 16, and have the same center spacing as the anode 24. On the other hand, the center spacing of the row wirings 34 extending in a direction orthogonal to them is, for example, the column wiring 32
It is about 0.3 to 1.5 (mm), three times that of The width dimension of the column direction wiring 32 is about 100 (μm), and the thickness dimension is, for example, about 12 (μm). On the other hand, the width dimension of the row wiring 34 is about 300 (μm), and the thickness dimension thereof is 20 (μm).
m).

The above-described column wiring 32 and row wiring 3
Numeral 4 is, for example, made of a thick-film conductor such as thick-film silver, and is formed on the inner surface 14 of the back plate 18 by using a thick-film screen printing method or the like. In addition, on the inner surface 14, in the direction along the column direction wiring 32,
4 are arranged so as to be located between the row-directional wirings 34 at a constant center interval similar to that of the column-directional wiring 32, and in a direction along the row-directional wiring 34, at a constant center interval similar to the column-directional wiring 32. A plurality of rectangular Y electrodes 38 arranged so as to be located between the wirings 32 are provided. As shown in FIG. 2A in which the main part of the cross section of the back plate 18 in the direction along the row direction wiring 34 is enlarged, the column direction wiring 32
The plurality of Y electrodes 38 are provided at positions partially overlapping with each other, and the Y electrodes 38 are electrically connected to the column wirings 32. Further, between each of the plurality of Y electrodes 38 and the column wiring 32 adjacent to the one to which the Y electrodes 38 are connected, there is a longitudinal extending along the column wiring 32 and electrically insulated therefrom. X electrodes 40 are provided. In this embodiment, the column wiring 32 and the row wiring 34 correspond to the first wiring and the second wiring, and the Y electrode 38 and the X electrode 40 correspond to the first electrode and the second electrode, respectively.

FIG. 3 shows the wirings 32 and 34 and the electrodes 3.
It is a top view for demonstrating the positional relationship of 8, 40, etc.
The above-mentioned Y electrode is formed, for example, so that the length dimension w in the direction along the column direction wiring 32 is about several (μm) to several hundred (μm). In this case, the distance g from the Y electrode 38 is, for example, several hundred (nm) to several hundred (μm).
, For example, about 0.5 to 20 (μm). The row direction wiring 34 is an X electrode 40
The X electrode 40 is electrically connected to the row-direction wiring 34.
Each of these electrodes 38 and 40 has a thickness of several (μm).
Hereafter, for example, about 500 (Å) is made of an alloy containing platinum as a main component. For example, after a film is formed by a thin film process such as a vacuum evaporation method or sputtering, a pattern is formed by using photolithography or the like. .

In the gap formed between the Y electrode 38 and the X electrode 40, there is provided an electron emission film 42 having a substantially circular planar shape and partially overlapping the two. FIG. 2A shows a cross section passing through the electron emission film 42. The electron emission film 42 is mainly composed of, for example, palladium oxide and has a thickness of, for example, about 100 (Å). The electron emission film 42 is subjected to an energization process called forming, and is locally broken, deformed, or altered, so that a crack on the order of nanometers is formed in a gap between the Y electrode 38 and the X electrode 40. 44. Therefore, although the Y-electrode 38 and the X-electrode 40 are provided so that the electron-emitting film 42 overlaps both of them, the electron-emitting film 42 has an extremely high electrical resistance and is substantially connected. Not. In addition,
The crack 44 is illustrated for one located at the left end in FIG.

The column wiring 32 and the row wiring 3
4, the interlayer insulating layer 36 has a longitudinal shape extending along the row direction wiring 34, but has one side in the longitudinal direction (the side where the row direction wiring 34 and the X electrode 40 overlap). ) Are formed in a wavy shape with the protrusions 36a intermittently provided at regular intervals, and thus the width is not uniform. The convex portion 36a is provided for each overlapping portion 46 of the plurality of column wirings 32 and the row wirings 34, where the insulating layer 36 is located above the row wirings 34.
Protrudes on both sides in the width direction. For this reason, since the interlayer insulating layer 36 is formed wider than the row direction wiring 34 in the overlapping portion 46, the interlayer insulating layer 36 covers the column direction wiring 32 and electrically insulates them. The insulating layer 36 reliably insulates the column wiring 32 and the row wiring 34, and there is no portion where these are electrically short-circuited (short-circuit defect).

On the other hand, in the portion where the concave portion 36b is provided between the convex portions 36a for each row direction wiring 34, on one side of the row direction wiring 34 overlapping with the X electrode 40, the insulating layer 36 is formed. Than in the width direction. Therefore, as shown in FIG.
Since there is a portion where the insulating layer 36 does not exist between the overlap portion 48 of the X electrode 4 and the X electrode 40, the row wiring 34 and the X electrode 40 are electrically connected there as described above. . The interlayer insulating layer 36 insulates the row wiring 34 provided so as to partially overlap the plurality of column wirings 32 and the plurality of X electrodes 40 from the column wiring 32, and It is provided for connection with the X electrode 40. FIG. 2B shows a cross section of the back plate 18 passing through the overlapping portion 48 in a direction along the row direction wiring 34, and as shown in FIG. The electrode 32 is not in contact with the row wiring 34, but the X electrode 40 not covered with the insulating layer 36 is in contact with the row wiring 34.

When driving the FED 10 configured as described above, a constant acceleration voltage of, for example, about 5 (kV) is constantly applied to the metal back 30 and, for example, a plurality of row-direction wiring Negative voltage (scanning voltage) sequentially at 34
When a positive voltage (signal voltage) is applied to a desired one of the plurality of column wirings 32 in synchronization with the scanning, the column wiring 32 and the row wiring 3
Electrons are emitted from the electron emission film 42 provided between the Y electrode 38 and the X electrode 40 to which a voltage is applied via the electron emission film 42 provided between the Y electrode 38 and the X electrode 40 due to a large voltage gradient. You. This electron is
When a predetermined positive voltage (acceleration voltage) is applied to the anode 24 provided on the front plate 16, it flies toward the anode 24. As a result, electrons collide with the phosphor layer 26 provided on the anode 24, and the phosphor layer 2
6 is caused to emit light. When this light emission was observed through the front plate 16, the color mixture of the phosphor layer 26 and the electrodes 38 and 40 were observed.
No light emission failure or the like caused by a short circuit or the like was observed. In this embodiment, one dot for display is formed at each intersection of the column wiring 32 and the row wiring 34.
One pixel is formed for each phosphor layer 26 of three colors arranged in the row direction corresponding to three dots.

The phosphor layer 26 is formed of a metal back 30.
Since the metal back 30 is extremely thin, electrons pass through the metal back 30 and enter the phosphor layer 26 to collide with the phosphor. On the other hand, the light generated in the phosphor layer 26 is reflected not only on the front plate 16 side but also on the rear plate 1.
The light traveling toward the rear plate 18 is also reflected toward the front plate 16 by the aluminum thin film 30. Therefore, most of the generated light passes through the front plate 16 and is emitted, thereby substantially improving the luminous efficiency.
That is, the FED 10 is arranged such that the phosphor layer 2
It is configured as a so-called transmission type display device for observing the light transmitted through 6. The FED 10 is provided with an exhaust hole or the like for exhausting air from the airtight container, but is omitted in the drawing.

The above-mentioned FED 10 is formed, for example, on a front plate 16 and a rear plate 18 with necessary films, and then sealed with a sealing glass such as lead glass via a spacer 22 with the surfaces 12 and 14 facing each other. It is manufactured by constituting a vacuum tube. In the manufacturing process, the back plate 18
Column direction wiring 32 and row direction wiring 3 which are formed on
4, that is, the step of forming the laminated wiring is performed according to, for example, a process chart shown in FIG. The main part of the method for manufacturing the back plate 18 will be described below with reference to FIGS. 4 and 5 and FIGS. 6A to 6F showing the state of film formation on the back plate inner surface 14 at each stage of the process. .

In FIG. 4, first, an electrode forming step SA1
In the above, the Y electrode 38 and the X electrode 40 are formed on the inner surface 14 of the back plate 18 by using a thin film forming technique.
That is, for example, in a vacuum chamber, an alloy mainly composed of platinum is formed on the inner surface 14 by sputtering or the like to a thickness of about 500 (等), taken out of the chamber, and spin-coated by the spin coating method or the like. 14 is coated with a photosensitive resin. This back plate 18 is
(° C.) and pre-baking at a temperature of about 90 (° C.).
After exposing and developing with a negative pattern corresponding to pattern No. 0, and drying again at a temperature of about 60 (° C.), unnecessary portions of titanium oxide were removed by ion milling or the like in a vacuum chamber and removed from the chamber. The substrate is treated with a developing solution (stripping solution) to remove the photosensitive resin. Thus, the Y electrode 38 and the X electrode 40 shown in FIGS. 1 to 3 are provided on the inner surface 14.

Next, in a column direction wiring forming step SA2, the column direction wiring 32 made of thick silver is formed so as to partially overlap the Y electrode 38 by using, for example, a thick film screen printing method. This step is performed, for example, according to each step shown in FIG. In FIG. 5, in a masking step SB <b> 1, a masking 52 is applied to a portion where the thick-film silver should not adhere, that is, a print-inhibited region 50. FIG.
(a) illustrates this stage. Each figure (a) in FIG.
In (f), only one pair of the electrodes 38 and 40, that is, only the intersection of the column wiring 32 and the row wiring 34 is shown. Here, the portion where thick film silver must not adhere is the vicinity of the gap between the electrodes 38 and 40 where the electron emitting portion, that is, the above-mentioned electron emitting film 42 is provided. The masking 52 is provided in a band shape intermittent in a direction substantially orthogonal to the longitudinal direction of the column-directional wiring 32 such that the mask 52 substantially covers the gap and exposes the Y electrode 38 at a portion overlapping the column-directional wiring 32. That is, the masking 52 is provided only at a position where the attachment of the thick film silver should be avoided. The masking 52 is obtained, for example, by dissolving and kneading an ethyl cellulose resin having a degree of polymerization of about 100 obtained by a viscosity measurement method in terpineol.
For example, after applying using thick film screen printing, 120
(℃) by drying at a temperature of about 5 (μm)
It is provided with a thickness of about.

Next, in a printing step SB2, a thick film silver paste is applied in a predetermined pattern, in this embodiment, a stripe pattern to a thickness of, for example, about 15 (μm).
This thick-film silver paste is, for example, a silver powder and a glass powder dispersed in a solvent together with a resin component. The paste composition is, for example, silver 75 (%) in weight percentage, glass 8
(%), About 3% resin, and about 14% solvent. The silver powder is, for example, a flake having an average particle size of about 0.2 (μm), and the glass powder has, for example, an average particle diameter of 0.3 (μm).
It is a Si-B-Pb-based amorphous glass with a softening point of about 450 (° C). The resin component is, for example, a mixture of two types of ethyl cellulose having a degree of polymerization of about 10 and 100 obtained by a viscosity measurement method, and the solvent is, for example, butyl carbitol acetate (BCA). The thick film silver paste thus configured has a larger contact angle with respect to the masking 52 than that with respect to the one surface 14 of the back plate 18,
The thick film silver paste hardly spreads on the masking 52. In this embodiment, the thick silver paste described above corresponds to a printing paste.

In the subsequent drying step SB3, the back plate 18 is placed in a drier and dried at a temperature of about 120 (° C.) to remove the solvent component in the paste and harden the paste. Then, in the firing step SB4, a heat treatment is performed in a firing furnace, for example, in an air atmosphere at a temperature of about 500 (° C.) for about 10 (minutes). Thereby, the organic components such as the resin in the dried film from which the solvent has been removed are burned off, and the silver powder and the glass component are melted and hardened in the cooling process of the heat treatment, for example, about 12 (μm). The column direction wiring 32 made of thick silver having a thickness is generated. At the same time as the formation of this thick film silver, the masking 52 made of an organic component is also burned off. FIG. 6 (b) illustrates this stage. Note that these masking or heating processes are repeated twice, for example, according to the required thickness of the column-directional wiring 32.

In the process of forming the column wirings 32 as described above, as shown in FIG.
Due to dripping or bleeding of the thick silver paste on the top,
The protruding portion 54 protruding from the screen plate printing pattern is formed in a part of the column direction wiring 32. However, since the protruding portion 54 is a portion covered by the interlayer insulating layer 36 and not in contact with other electrodes or wirings as shown in FIG. There is no inconvenience.

In FIG. 6B, the masking 52 existing before the heat treatment is indicated by a dashed line. As shown in the figure, at the position where the masking 52 is provided, the protruding portion 54 is not formed in the column wiring 32. This is because, as described above, the thick silver paste does not spread thereon due to the large contact angle with the masking 52. On the other hand, at a position deviating from the column direction wiring 32, that is, at a position deviating from the print pattern, an unnecessary thick film silver paste adheres on the masking 52, that is, an unnecessary pattern 56 is generated. This unnecessary pattern 56 is formed, for example, when there is a defect in screen plate making, and is located at a position where the electrodes 38 and 40 are short-circuited, that is, on the gap therebetween. It is removed from the print-inhibited area 50 during the heating process. That is, masking 5
2 is burned out, the organic components constituting it are gasified, and the generated steam causes the unnecessary pattern 56 to disappear.
Is carried out of the print-inhibited area 50 and is removed. Therefore, the function of the FED 10 is not impaired even if it is applied to the position where the above-mentioned short-circuit occurs. In this embodiment, the firing step SB4 corresponds to the removing step.

Returning to FIG. 4, an interlayer insulating layer forming step SA3
In the above, a stripe pattern extending in a direction perpendicular to the column direction wiring 32 using a thick film screen printing method as in the case of the column direction wiring 32, and the thickness dimension on the column direction wiring 32 is An interlayer insulating layer 36 of about 28 (μm) is formed. In this step, the paste used for thick film screen printing is a thick film insulating paste in which glass powder is dispersed in a solvent together with a resin component, and the printing or baking treatment is repeated, for example, about five times depending on the required thickness. FIG.
(c) illustrates this stage.

In the subsequent row-direction wiring forming step SA4, the thick film screen printing method is used to form a film on the above-mentioned stripe-shaped interlayer insulation layer 36, similarly to the case of the column-direction wiring 32 and the interlayer insulation layer 36. The above-mentioned row-direction wirings 34 having a film thickness of, for example, about 20 (μm) are formed in a stripe pattern extending along the line. The paste used in this step is the same as that in the case of the column direction wiring 32, and the number of repetitions of the printing or baking process is the same. FIG. 6D shows this stage. Although not particularly shown in the drawing, if necessary, a thick film silver paste can be applied after masking 52 as in the formation of the column-directional wiring 32. In FIG. 6D, unlike the above-described FIG.
6, the column-directional wiring 32
The case where it is made to be insulated is shown.

In the electron emission film forming step SA5, an electron emission film 42 is formed between the Y electrode 38 and the X electrode 40 so as to straddle them. This electron emission film 42
For example, by applying an organic palladium paste by ink jet printing or the like, drying it at a temperature of about 70 (° C.), for example, and then performing a heat treatment at a temperature of about 400 (° C.) in an air atmosphere, Organic palladium is decomposed and oxidized to produce palladium oxide with a thickness of about 100 (Å). FIG. 6 (e) illustrates this stage. The above-mentioned organic palladium paste is obtained by dispersing a metal organic compound of palladium in a solvent. Alternatively, a paste in which ultrafine particles of palladium are dispersed in a solvent may be used.

Then, in the forming step SA6, a pulse voltage is sequentially applied between the plurality of column direction wirings 32 and the row direction wirings 34 to energize the electron emission film 42, thereby partially changing the structure of the electron emission film 42. The crack 44 is generated by breaking or reforming. The forming process includes, for example, step-up 10 (seconds), step-down 10 (seconds),
This was performed by applying a triangular wave of about 5 (V) about 10 times. As a result, the electron emission film 42 has an electron emission function.

In short, in this embodiment, in the state where the print-inhibited area 50 is covered with the masking 52, the film-forming surface 1
4 is coated with a thick-film silver paste.
In the case where there is a defect in the plate making for forming the layer 2 or the thick film silver paste bleeds on the film forming surface 14, the useless thick film silver paste (the unnecessary pattern 56) is used in the print prohibited area 50. Instead of being directly applied to the film forming surface 14, it is applied on the masking 52, and in the firing step SB 4,
It is removed from the film forming surface 14 together with the masking 52. Therefore, the thick film silver of the unnecessary pattern 56 is suppressed from adhering to the print prohibition area 50 and extending therefrom. On the other hand, even if the protruding portion 54 due to bleeding or the like occurs outside the print pattern outside the print prohibited area 50, the back plate 1
8 does not cause any inconvenience. Therefore, when manufacturing the back plate 18, the occurrence of defects due to the bleeding of the printing paste and the defects of the plate making is suppressed.

In this embodiment, the masking 5
2 dissolves ethyl cellulose resin in terpineol
Since the masking material is formed from the kneaded masking material, no decomposition residue remains after the masking 52 is burned off by the heat treatment.

Preferably, in this embodiment, an organic compound is used as a masking material, and the columnar wiring 32 is formed by heat-treating a thick film silver paste.
Since the masking 52 is burned off at the same time in the process of forming the mask, the number of steps for removing the masking 52 does not increase or the process does not become complicated. In particular, since the masking material does not contain metals or inorganic compounds that remain after the masking 52 is burned off, the residues do not pose a problem.

In this embodiment, the column-directional wiring 3
Since the masking 52 is provided only in the region 50 where the thick film silver constituting the FED 10 must not adhere to the function of the FED 10, a region outside of the printing pattern but having no functional problem, for example, a protrusion. The thick film silver paste adhered to the portion where the portion 54 is formed is not carried by the steam generated in the burning process of the masking 52 in the baking step SB4, and is fixed to the printing position as it is. For this reason, the thick-film silver paste adhered to the unhindered area cannot be carried to the print-inhibited area 50 during the baking process, so that the thick-film silver is further prevented from sticking to the print-inhibited area 50. .

In this embodiment, the masking 5
No. 2 has a large contact angle with the thick film silver paste, so that the thick film silver paste is difficult to spread on the masking 52, so that an increase in the pattern width dimension caused by bleeding, paste dripping and the like is suppressed. Therefore, a thick film pattern with higher definition can be formed.

Next, another embodiment of the present invention will be described. In the following embodiments, portions common to the above-described embodiments will be denoted by the same reference numerals and description thereof will be omitted.

FIG. 7 is a process diagram for explaining a main part of a manufacturing process when the present invention is applied to the front plate 16 having the phosphor layer 26. Hereinafter, FIG. 8A to FIG.
A method for forming the phosphor layer 26 will be described with reference to FIG. First, in the anode forming step SC1, an ITO film is formed on the inner surface 12 of the front plate using a thin film forming technique such as vapor deposition or sputtering, and is patterned as necessary to form the anode 24 described above. Next, Black
In the mask forming step SC2, a black insulating paste is applied to substantially the entire surface 12 by using a thick film screen printing method or the like, and is exposed and developed in a predetermined pattern.
By performing a heat treatment at a firing temperature of about 0 (° C.), a black mask 60 having a plurality of stripe-shaped openings 58 is formed. FIG. 8A shows this stage. However, the anode 24 is omitted in the figure. The above-mentioned black insulating paste is obtained by dispersing a black pigment and glass powder in a photosensitive resin, for example. As the black pigment, for example, carbon powder is preferably used, and as the photosensitive resin, for example, one containing polyvinyl alcohol-ammonium dichromate as a main component is preferably used.

In the subsequent phosphor layer forming step SC3,
The red (R), blue (B), and green (G) phosphors are sequentially applied to the inside of the above-described opening 58 to form the phosphor layer 26.
To form As the phosphor, for example, red light-emitting Y ₂ O ₂
S: Eu, blue light-emitting ZnS: Ag, green light-emitting ZnS: Cu, Al and the like are used. The phosphor layer 26 was formed using pastes containing these phosphor powders, for example, for each color according to the process shown in FIG. That is, when forming the phosphor layer 26 (R) for emitting red light, first, in the masking step SB1, the phosphor layer 26 for emitting blue light is used.
A masking 62 is provided at a position where the phosphor layer 26 (G) for emitting the green light is to be formed, and a black mask 60 is provided.
Cover 58. FIG. 8B shows this stage. In the figure, the left end and the third opening 58 from the left are positions where the red phosphor layer 26 (R) is formed, and the other openings 58 are covered with the masking 62. In this embodiment, a masking material is used by using a photosensitive resin solution such as polyvinyl alcohol-ammonium dichromate as a masking material, applying the solution over the entire surface of the substrate by spin coating or the like, and exposing and developing the masking 62. Formed.

Next, in a printing step SB2, a phosphor paste is applied to the inside of the opening 58 by using, for example, a thick film screen printing method. As the phosphor paste, for example, those obtained by kneading the phosphor powder, a resin component such as ethyl cellulose, a solvent such as terpineol, and a small amount of a potassium silicate solution are used. Then, in a drying step SB3, the paste is dried at a temperature of, for example, about 120 (° C.) to remove the solvent in the paste.
Perform heat treatment at a temperature of about 0 (° C). Thereby, the organic components in the phosphor paste are removed, and the phosphor powders are fixed to each other and to the inner surface 12 of the front plate by the binding force or intermolecular force of potassium silicate, and at the same time, the masking 62 is burned off. Can be FIG. 8C shows a state after the red light emitting phosphor layer 26 (R) is formed in this manner.

At this time, if there is a defect such as a pinhole in the screen plate used for applying the phosphor paste, a position other than the opening 58 where the red phosphor layer 26 is provided, for example, a phosphor layer of another emission color. The phosphor paste also adheres to the opening 58 provided with 26 (B), 26 (G) and the like. FIG.
Reference numeral 64 indicated by a dashed line in (c) denotes an unnecessary pattern in which the phosphor paste is attached to such a portion. Also in this embodiment, the unnecessary pattern 64 is formed by the masking 6
Since the phosphor 2 is removed at the same time as it is burned off, the phosphor emitting red light does not adhere to the position where the phosphor of another emission color is to be provided. Also, the phosphor paste applied to the correct position (the position where the red light emitting phosphor layer 26 is to be provided at this stage) is repelled by the masking 62 having a large contact angle and the position where the phosphor of another emission color is to be provided. Since the fluorescent material cannot spread, there is no occurrence of color mixing of the phosphor due to the spread (flow or dripping).

The phosphors emitting blue light and green light are also processed according to the masking step SB1 to the baking step SB4, respectively, so that the three phosphor layers 26 of three colors RGB are formed on the inner surface 12 of the front plate in a stripe shape. They are provided side by side. FIG. 8D shows this stage. When the blue light emitting phosphor layer 26 (B) is provided, the mask 58 is formed on the red light emitting phosphor layer 26 (R) and the green light emitting phosphor layer 26 (G) in the opening 58 in the masking step SB1. When the green light emitting phosphor layer 26 (G) is provided by masking 62 on the red light emitting phosphor layer 26 (R) and the blue light emitting phosphor layer 26 (B) in the masking step SB1. Is provided with a masking 62. Therefore, any phosphor paste does not unnecessarily adhere to the position where the phosphor of another emission color is provided. Therefore, in this embodiment, the position where a phosphor different from the one to be coated is to be provided corresponds to the print prohibited area.

Returning to FIG. 7, the metal back forming step S
In C4, the metal back 30 is formed on the black mask 60 and the phosphor layer 26 formed as described above. The metal back 30 is formed by, for example, performing a filming process of applying a resin solution such as a lacquer solution over the entire surface 12, depositing an aluminum thin film in a vacuum chamber, and then performing a heating process. This can be performed by burning out the filming film.

In short, also in this embodiment, since the phosphor paste is applied to the one surface 12 in a state where the print-inhibited area where the phosphor layer 26 of another emission color is to be provided is covered with the masking 62, defects in the plate making can be obtained. Is present or the phosphor paste bleeds on the surface 12, the unnecessary phosphor paste is not directly applied on the surface 12 but is applied on the masking 62 in the print-inhibited area, and the firing step S
At B4, the masking 62 and the surface 12 are removed. For this reason, unnecessary phosphor paste is prevented from adhering to the print-inhibited area, and is prevented from sticking to the unnecessary phosphor paste, so that color mixing of the phosphor is suitably suppressed.

In this embodiment, three color phosphor layers 26 (R), 26 (B) and 26 (G) are provided on one surface 12, but are formed from three kinds of phosphor pastes. The masking process SB1 to the firing process S
B4 is performed respectively. Therefore, since all the phosphor paste is applied avoiding the area on the one surface 12 which should not adhere, that is, the printing prohibited area where another phosphor is provided, the FED 1 due to the unnecessary phosphor paste adhesion is applied.
The defect of 0, that is, color mixing is further suppressed.

While the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be embodied in still another embodiment.

For example, in the embodiment, the back plate 18 constituting the color display FED 10 which is an image display device is used.
Alternatively, the case where the present invention is applied to the method of manufacturing the front plate 16 has been described. However, if the display device substrate includes a plurality of types of films including a thick film pattern on the surfaces 12 and 14, other types of films may be used. The present invention is similarly applied to a display substrate constituting a color or monochrome display device such as a fluorescent display tube or a PDP.

In the embodiment shown in FIGS. 1 to 6, in the process of forming a film on
2, the present invention is applied only when forming another thick film pattern, for example, when forming the row direction wiring 34 or the electron emission film 42. If the adhesion to other parts can occur and the adhesion is a problem, the present invention can be similarly applied.

Further, in the embodiment, the masking 52 is applied only to the area 50 where the attachment of the unnecessary pattern 56 is particularly prohibited. However, all parts except the part to be subjected to the thick film screen printing are covered with the masking 52. You may.

In the embodiments, the masking process is performed by using the thick film screen printing method, but the method may be appropriately changed according to the type of the masking material and the masking shape. For example, a film similar to the case of printing may be formed by attaching a film or sheet, or a pattern may be formed by photolithography technology, or vacuum evaporation, sputtering, plating,
It can also be formed by electroforming.

In the embodiment, the electrodes 38, 40
And the like are formed by the thin-film technique, so that the masking 52 was not provided at the time of the formation.
In the case where 0 is formed by thick film screen printing, the present invention can be applied as necessary also in the forming process.

In the embodiment, the masking 52
And a removing step for removing the unnecessary pattern 56,
Although the heat treatment in the firing step SB4 for forming a thick film from the thick film print paste is also performed, the removal step may be separately performed prior to the heat treatment. That is, for example, a washing process in which the thick film paste is washed with a liquid that does not dissolve the thick film paste, for example, when the thick film paste is insoluble in water, and with the solvent when the thick film paste is insoluble in a specific solvent, is used. The unnecessary pattern 56 can also be removed by performing the process.

Further, the thick silver paste for forming the wirings 32 and 34 is not limited to the one shown in the embodiment of FIGS. 1 to 6 and may take various structures. For example, the composition ratio of each component is about 65 to 90 (%) silver, and 2 to 15
(%), A resin of about 2 to 7 (%) and a solvent of about 5 to 20 (%) are preferably used. Also, as silver powder,
For example, flakes or spheres having an average particle size of about 0.2 to 0.3 (μm) are preferably used. However, in order to obtain the highest possible conductivity, it is preferable to use a flake-like material as shown in the embodiment. As the glass powder, for example, a low softening point glass having a softening point of about 380 to 470 (° C.) is preferable. In addition to the above-mentioned Si-B-Pb-based glass, Zn-Pb-based glass and the like are also suitably used. The resin component may be an acrylonitrile resin, a methylcellulose resin, or the like, and the solvent may be terpineol, cellosolve acetate, or the like.

In the embodiment, the masking 52
And the like are formed of a material having a large contact angle of the thick film printing paste to be applied. However, since the paste adhered on the masking 52 is removed from the film forming surface in a subsequent removing step, the contact angle is small. It may be made of a material.

Although not specifically exemplified, the present invention can be variously modified without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a configuration of an FED in which a display substrate manufacturing method according to an embodiment of the present invention is applied to a manufacturing process.

2 (a) is an enlarged view of a main part of the rear plate in FIG. 1 taken along the line IIa-IIa, and FIG. 2 (b) is an enlarged view of a main part of the rear plate taken along the line IIb-IIb.

FIG. 3 is an enlarged plan view of a main part for explaining a mutual relation of wiring on a back plate in the FED of FIG. 1;

FIG. 4 is a process diagram illustrating a process of forming electrodes, wirings, and the like provided on the back plate of the FED in FIG. 1;

FIG. 5 is a process diagram illustrating the column-direction wiring forming process of FIG. 4 in more detail.

FIGS. 6 (a) to 6 (f) are diagrams for explaining a film formation state at each stage of FIG. 4;

FIG. 7 is a process diagram for describing a case where the present invention is applied to the manufacturing process of the front plate of the FED of FIG. 1;

8 (a) to 8 (d) are views for explaining a film formation state in a main step of FIG. 7;

[Explanation of symbols]

 16: Front plate, 18: Back plate (display substrate) 32: Row direction wiring (thick film pattern) 50: Printing prohibited area 52: Masking

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09F 9/30 337 G09F 9/30 337 5E343 H01J 9/227 H01J 9/227 CE // H05K 3/12 610 H05K 3/12 610P (72) Inventor Kota Hirakawa 3-1-1, Noritakeshinmachi, Nishi-ku, Nagoya City, Aichi Prefecture Inside Noritake Electronics Industry Co., Ltd. (72) Inventor Shinsuke Mori 3-1-1, Noritakeshinmachi, Nishi-ku, Nagoya City, Aichi Prefecture No. 36 Noritake Electronics Co., Ltd. F-term (reference) 2C035 AA06 FD51 FD52 2H113 AA04 AA05 BA10 BB09 BB22 BB32 CA15 CA32 DA04 DA43 DA52 FA10 FA29 FA48 5C027 AA02 BB01 BB02 5C028 FF06 FF14 BA13A BA12A DB04 EA04 EA05 EA10 EB02 EC02 FA01 FA02 FB01 FB02 FB12 FB15 FB20 GB10 5E343 AA02 AA11 BB72 DD03 ER35 FF02 FF11 FF12 GG08

Claims (3)

[Claims] 1. A method for manufacturing a display substrate by forming a plurality of types of films including a thick film pattern on a film forming surface of a substrate, the method comprising forming the thick film pattern on the film forming surface. A masking step of covering a predetermined print-inhibited area to which the print paste must not adhere with a predetermined masking material, and printing the print paste in a predetermined pattern on the masked film forming surface in a predetermined pattern. A method for manufacturing a display substrate, comprising: a printing step; and a removing step of removing the masking material after the printing step. 2. The masking step uses an organic compound as the masking material, and the removing step heats the print paste to form a thick film and simultaneously burns off the masking material. The method for manufacturing a display substrate according to claim 1, which is a step. 3. The method according to claim 1, wherein the masking material has a larger contact angle with the printing paste than the film forming surface.