JP2004353021A - Metal mask for sputtering - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal mask for sputtering, which does not give an adverse effect such as increase in an ohmic value due to moisture adsorbed in a resinous salient, to a transparent conductive film, even when the film is formed with the use of the metal mask provided with the resinous salient for sputtering. <P>SOLUTION: The metal mask 20 used for forming a multilayerd transparent conductive film on a glass substrate by sputtering has the salient 23 of a resin containing 0.01 to 0.2% moisture on the surface contacting with the region other than an opening 21 of the glass substrate. The area of the salient is approximately 30% per unit area. The planar shape of the salient is a stripe shape. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a jig for an apparatus for manufacturing a color filter used for a liquid crystal display device or the like, and particularly to a metal mask for sputtering when a transparent conductive film is formed on a glass substrate.
[0002]
[Prior art]
FIG. 4 is a plan view schematically showing an example of a color filter used in a liquid crystal display device or the like. FIG. 5 is a cross-sectional view taken along line XX ′ of the color filter shown in FIG.
As shown in FIGS. 4 and 5, a color filter used in a liquid crystal display device or the like has a black matrix (41), a colored pixel (42), and a transparent conductive film (43) formed on a glass substrate (40). It was done.
[0003]
The black matrix (41) is a matrix having light-shielding properties, the colored pixel (42) has, for example, a filter function of red, green, and blue, and the transparent conductive film (43) is transparent. Are provided as simple electrodes.
The transparent conductive film is formed on the glass substrate on which the black matrix and the colored pixels are formed, for example, by a sputtering method using ITO (Indium Tin Oxide).
[0004]
FIGS. 4 and 5 schematically show a color filter, in which twelve colored pixels are shown. In an actual color filter, for example, a screen having a diagonal width of 14 inches is about several hundred μm. Are arranged in a large number.
Further, the color filters shown in FIGS. 4 and 5 represent one color filter corresponding to one liquid crystal display device, and when used in a liquid crystal display device, for example, a peripheral portion of the color filter is used. A sealant (not shown) is provided on a portion where the glass substrate (40) is exposed, and is bonded to a counter substrate to obtain a liquid crystal display device.
[0005]
FIG. 6 is a plan view showing an example of manufacturing a large number of color filters by imposing, for example, a 14-inch diagonal color filter.
As shown in FIG. 6, in this example, a 14-inch diagonal color filter (61) is manufactured with four large-sized glass substrates (60).
FIG. 7 is a plan view showing a state of a glass substrate and a metal mask for sputtering when a transparent conductive film is formed on a large-sized glass substrate by a sputtering method. FIG. 8 is a sectional view taken along line XX ′ of FIG.
[0006]
The metal mask for sputtering is generally a metal such as stainless steel SUS430, 42 alloy (42 wt% nickel, residual iron) and has a thickness of about 0.2 mm to 0.7 mm. The opening of the metal mask for sputtering is formed by, for example, a photo-etching method.
[0007]
When forming a transparent conductive film, as shown in FIGS. 7 and 8, an opening (71) is formed on a glass substrate (80) on which a black matrix (81) and a colored pixel (82) are formed. A metal mask for metal sputtering (70) having a black matrix (81) and a colored pixel (82) of a glass substrate (80) and an opening (71) of the metal mask for sputtering (70) are aligned and overlapped; Sputtering is performed in the overlapped state as indicated by the arrow to form a transparent conductive film on the black matrix (81) and the colored pixels (82) below the opening (71).
[0008]
FIG. 9 is an enlarged sectional view showing a portion A in FIG. The alignment of the black matrix (81) and the colored pixel (82) with the opening (71) is actually performed by a metal mask for sputtering (70) having an inverted convex cross section as shown in FIG. Are aligned and overlapped on the surface of the glass substrate (80) between the black matrices (81) of the imposed 14-inch diagonal color filters. The protruding portion (B) of the mask (70) comes into contact with the black matrix (81) or the colored pixel (82), and damages the black matrix (81) or the colored pixel (82), resulting in a defective color filter. There is.
Alternatively, for example, dust of the transparent conductive film that has adhered to the metal mask during use may adhere again to the colored pixel (82).
[0009]
FIG. 3 is a cross-sectional view showing an enlarged part of an example of a sputter metal mask developed to prevent such scratches.
As shown in FIG. 3, the metal mask for sputtering (10) is provided by using a metal mask portion (12) of a metal provided with an opening (11) and a resin for the metal mask portion (12). (13).
[0010]
The convex portion (13) is a portion that comes into contact with the glass substrate when the metal mask for sputtering is superimposed on the glass substrate.
In this metal mask for sputtering, a portion in contact with the glass substrate is made of a soft resin, so that when the glass substrate is aligned with the opening of the metal mask for sputtering, the projections of the metal mask for sputtering are black matrix or colored. Even if it touches the pixel, it does not damage the black matrix or the colored pixel.
[0011]
However, when a transparent conductive film made of ITO is formed by using a metal mask for sputtering provided with the convex portion (13) of the resin, there arises a problem that the properties of the transparent conductive film, particularly the resistance value and the transmittance are adversely affected. I was
This is presumed to be that the moisture adsorbed on the resin convex portion is released under reduced pressure, that is, during the evacuation in the sputtering apparatus, and during the film formation, to increase the characteristics of the transparent conductive film, for example, the resistance value. ing. When the resistance value is abnormally increased due to the moisture, the product is defective.
[0012]
In addition, when such an abnormal increase in resistance occurs in actual work, it is necessary to reduce the water content of the convex portion of the resin and to return the sputtering apparatus to a normal state. As an emergency measure, an idle operation in which only a metal mask for sputtering is put into a sputtering apparatus is performed, and dehydration treatment is performed under reduced pressure.
[0013]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-212721
[Problems to be solved by the invention]
The present invention has been made to solve the above problem, and even when a transparent conductive film is formed using a metal mask for sputtering provided with a convex portion of a resin, the moisture absorbed in the convex portion of the resin is It is an object of the present invention to provide a metal mask for sputtering that is not adversely affected by characteristics of the transparent conductive film, particularly, an increase in resistance value.
[0015]
[Means for Solving the Problems]
According to the present invention, in a metal mask for sputtering in which a transparent conductive film is formed by being superimposed on a glass substrate, the surface excluding the opening has a water content of 0.01% to 0.2% on a surface in contact with the glass substrate. %, Which is a metal mask for sputtering, wherein a convex portion of resin is provided.
[0016]
Further, the present invention is the metal mask for sputtering according to the above invention, wherein the area of the projection is approximately 30% per unit area.
[0017]
Further, the present invention is the metal mask for sputtering according to the above invention, wherein the planar shape of the projection is a stripe shape.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a plan view showing an embodiment of a metal mask for sputtering according to the present invention. This plan view shows only one corner of the metal mask for sputtering. FIG. 2 is a cross-sectional view taken along line XX ′ of FIG.
[0019]
As shown in FIGS. 1 and 2, a metal mask for sputtering (20) according to the present invention includes a metal mask portion (22) of a metal provided with an opening (21) and a metal mask portion (22) thereof. And a convex portion (23) of a resin provided on the substrate. In this embodiment, a stripe-shaped projection is provided.
The convex portion (23) of the resin becomes a portion that comes into contact with the glass substrate when the metal mask for sputtering is superimposed on the glass substrate.
[0020]
The convex portion (23) of the resin is provided by, for example, a screen printing method. As the ink to be used, for example, a solvent-free UV curable ink using a polyacrylate is preferable. When producing this UV-curable ink, the water content of the polyacrylate as a raw material and the water content of the polyacrylate during the production process are controlled so that moisture does not enter the polyacrylate. Manufacturing.
The water content is preferably 0.01% to 0.2%, and the water content is measured by, for example, a Karl Fischer moisture meter. The metal mask for sputtering on which the resin protrusions (23) are formed is stored in a low-humidity container.
[0021]
Specifically, the convex portion (23) of the resin is formed by screen printing on the metal mask portion (22) having a thickness (D1) of about 0.2 mm by a screen printing method. 23) is formed.
The thickness (D2) of the projection is preferably in the range of 0.02 mm to 0.09 mm. In order to reduce the water content of the projections, the thickness is preferably low, but a thickness of 0.02 mm or more is required to keep an effective distance between the glass substrate and the metal mask for sputtering. .
Further, the thickness of the convex portion that can be formed by one printing is about 0.09 mm, and thus the thickness of the convex portion is in the range of 0.02 mm to 0.09 mm.
[0022]
Further, the area of the projection is preferably in the range of 30% ± 10% per unit area. In order to reduce the water content of the projections, it is preferable that the area is small, but if it is less than 20%, the strength is insufficient. Further, since the area per unit area of the convex portion in the related art is approximately 45%, the effect of reducing the area of the convex portion is small at 40% or more.
Specifically, the protrusions (23) of the striped resin shown in FIG. 2 have a width (W) of about 2.0 mm and a pitch (P) of about 6.5 mm, and have an area per unit area of 2.0 mm. /6.5=about 30%.
[0023]
The planar shape of the projection is not particularly limited, and may be, for example, a circle or a rectangle. However, the stripe-shaped projection can be formed stably with high dimensional accuracy. Is preferred.
[0024]
As described above, the metal mask for sputtering according to the present invention has a low water content. A transparent conductive film made of ITO having a resistivity of 30 Ω / □ or less can be easily manufactured.
[0025]
【The invention's effect】
According to the present invention, a resin convex portion having a water content of 0.01% to 0.2% is provided on a surface in contact with a glass substrate in a region excluding an opening, and an area per unit area of the convex portion is substantially reduced. Since the sputtering metal mask is set to 30%, the sputtering metal mask does not have an increase in resistance due to moisture adsorbed on the convex portion of the resin in the sputter deposition.
[Brief description of the drawings]
FIG. 1 is a plan view showing an embodiment of a metal mask for sputtering according to the present invention.
FIG. 2 is a cross-sectional view taken along line XX ′ of the metal mask for sputtering shown in FIG.
FIG. 3 is an enlarged cross-sectional view showing a part of an example of a sputter metal mask developed to prevent scratches.
FIG. 4 is a plan view schematically showing an example of a color filter used in a liquid crystal display device or the like.
FIG. 5 is a cross-sectional view taken along line XX ′ of the color filter shown in FIG.
FIG. 6 is a plan view showing an example of a state in which a color filter is imposed and manufactured.
FIG. 7 is a plan view showing a state of a glass substrate and a metal mask for sputtering when a transparent conductive film is formed.
8 is a cross-sectional view taken along line XX 'of the state of the glass substrate and the metal mask for sputtering shown in FIG.
FIG. 9 is an enlarged sectional view showing a portion A in FIG. 8;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Sputtering metal mask 11, 21 ... Opening 12, 22 ... Metal mask part 13, 23 ... Resin convex part 20 ... Sputtering metal mask 30, 40, 60, 80 ... Glass substrate 31, 41, 81 black matrixes 32, 42, 82 colored pixels 33, 43 transparent conductive film 61 diagonal 14-inch color filter 70 metal mask B for sputtering in the conventional method convex part D1 in the conventional method Thickness D2: Thickness of convex part P: Pitch of convex part W: Width of convex part

Claims (3)

In a metal mask for sputtering in which a transparent conductive film is formed by being superimposed on a glass substrate, a resin having a water content of 0.01% to 0.2% is provided on a surface in contact with the glass substrate except for an opening thereof. A metal mask for sputtering, wherein a convex portion is provided. 2. The sputtering metal mask according to claim 1, wherein the area of the projection is approximately 30% per unit area. The metal mask for sputtering according to claim 1, wherein a planar shape of the convex portion is a stripe shape.

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