JP2002030415A - Mask for conductive film patterning - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mask for conductive film patterning, by which the process can be shortened, appearance defects such as flaw, blot and spark mark can be prevented, productivity can be greatly improved, and accordingly, usability in the subsequent process and durability during use can be improved remarkably. SOLUTION: The mask for conductive film patterning is a mask for forming pattern on a substrate, and the corners of the mask are rounded to 0.01-0.1 mm R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conductive film patterning mask for forming a pattern on a substrate. The mask of the present invention is used, for example, to pattern and form a conductive film used for a liquid crystal display device (LCD) or the like.

[0002]

2. Description of the Related Art Conventionally, as a method of patterning a conductive film, an etching method typified by a print mask or photolithography after film formation, and a method of forming a film using a mask patterned at the time of film formation are known. It is known (for example, Japanese Patent Laid-Open No. 5-117839).

[0003]

However, the conventional method of patterning a conductive film has a disadvantage that the etching method requires a photolithography step, and thus the steps are long and the cost is high. Had a problem that it was difficult to use. Further, in the mask film formation using a mask, there is a defect that a scratch is generated at a pattern boundary due to heating of the substrate during film formation due to a slight difference in thermal expansion coefficient between the substrate and the mask material. Further, there is a disadvantage that scratches and sparks are easily generated due to the processing angle at the pattern boundary of the mask. Furthermore, when the surface of the mask is a rolled mirror surface, there is a disadvantage that adhesion to the conductive film repeatedly deposited on the mask is poor, and the film is easily peeled off. In addition, when the conductive film is formed by sputtering when the substrate and the mask are in close contact, charge transfer occurs between the conductive film and the mask, and at that time, there is a disadvantage that a spark is generated. There was no problem when using it industrially because it was not used or required special consideration in use.

An object of the present invention is to solve the above-mentioned disadvantages of the prior art, to shorten the process, to eliminate appearance defects such as scratches, bleeding, and spark marks, and to achieve a remarkably excellent productivity, and thus to be used in a subsequent process. An object of the present invention is to provide a mask for patterning a conductive film, which has significantly improved easiness and durability in use.

[0005]

In order to achieve the above object, the present invention employs the following constitution. (1) A mask for forming a pattern on a substrate, wherein a corner portion of the mask has a roundness of R = 0.01 to 0.1 mm. mask.

(2) The conductive film patterning mask according to the above (1), wherein the processing for imparting roundness to the corners of the mask is performed by immersing it in an etchant after the pattern processing.

(3) The above-described (1) or (1), wherein the portion of the mask opposite to the side in contact with the substrate has a center line average roughness Ra of 0.1 to 5.0 μm. The mask for patterning a conductive film according to 2).

(4) A mask for forming a pattern on a substrate, wherein a part of the mask portion on the side in contact with the substrate on which the pattern is formed has a shape with a gap not in contact with the substrate. Any of the above (1) to (3), wherein the contact area between the substrate and the substrate except for the gap between the mask and the substrate is embossed so that the contact area with the substrate is 50 to 75%. 4. The conductive film patterning mask according to item 1.

(5) The conductive film patterning as described in any of (1) to (4) above, which is a mask for patterning and forming a conductive thin film of 10 to 5000 Å. For mask.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, the mask for patterning a conductive film of the present invention is a mask for forming a pattern on a substrate. Preferably, the surface roughness of the part opposite to the side contacting with the substrate, or preferably the contact area of the part on the side contacting with the substrate is set to a specific range.

The substrate used in the present invention is not particularly limited, and glass having high light transmittance, excellent mechanical strength, and excellent dimensional stability is optimal, but other materials such as polyimide resin, acrylic resin, polyester resin and the like can be used. Plastic plates can also be used. When used for a color filter or the like, various plastic and inorganic thin films that satisfy the required characteristics of the color filter on glass or plastic and are patterned and laminated and combined may be used.

The material of the mask used in the present invention is not particularly limited, but is preferably the same material as the substrate, that is, glass or a plastic plate. Further, metals in consideration of handleability, durability, workability, and coefficient of thermal expansion are also preferable, and can be selected from many metal or alloy plates such as tungsten, molybdenum, iron, chromium, nickel, stainless steel, and 42 alloy. .

FIG. 2 is a sectional view taken along the line AA of FIG. 1 showing an example of the patterning mask of the present invention used in the first embodiment. FIG. 4 is a sectional view of the patterning mask of the present invention used in the second embodiment. FIG. 4 is a cross-sectional view taken along the line AA of FIG. 3 illustrating an example of a mask for use. In the present invention, as shown in FIGS. 2 and 4, the patterned portion of the mask 1 has a shape having a gap T that does not contact the substrate. If the gap T is too large, there is a drawback that bleeding occurs. If the gap T is too small, appearance defects such as scratches and spark marks are not eliminated. Therefore, the gap T may be 0.01 to 0.5 mm. Preferably, it is more preferably in the range of 0.03 to 0.15 mm. An arbitrary method such as cutting and bonding (the same material or different materials) can be adopted as a method of forming a shape having a gap.

The thickness D of the mask is 0.2 to 1.0 m.
m, more preferably 0.25 to 0.5
It is in the range of 0 mm.

If the thickness D of the mask is more than 1.0 mm, the thickness distribution at the pattern boundary is poor and bleeds easily. Therefore, it is necessary to take measures such as providing a taper at the corner of the mask opening, which is not preferable.

Further, since there is a disadvantage that a scratch is easily generated due to a processing angle at the pattern boundary of the mask, FIGS.
As shown in FIG. 5, it is preferable to make the corners of the mask have a roundness R, and the roundness R has a radius R = 0.01 to 0.1.
It is preferably 1 mm roundness, and more preferably R
= 0.02 to 0.08 mm, it is preferable to make it hard to scratch. A process of giving a roundness to all corners present when viewed from the cross section of the mask can be easily performed by dipping in an etchant after pattern processing such as an opening. Of course, the composition, conditions, and detailed form of the roundness of the etchant may be any detailed form of the composition, conditions, and roundness as long as the generation of scratches is minimized.

Further, when the surface of the mask is a rolled mirror surface,
Poor adhesion with the conductive film repeatedly deposited on the mask,
In the present invention, as shown in FIGS. 2 and 4, the center line surface roughness Ra of the portion 2 on the side opposite to the side in contact with the substrate is 0.1 to 5 because there is a defect that the film is easily peeled off. 0.0μ
And more preferably 0.2
It is preferable to make the film hardly peeled off in a range of from 2.0 μm to 2.0 μm. The method and form of surface roughening may be any method and form as long as the adhesion is as good as possible.

The center line surface roughness Ra is ANSI / ASME
B46.1-1985, and is calculated by the following equation (1).

[0019]

(Equation 1)

[0020] Here, Ra: center line surface roughness L: measured length y: distance from the center line to the roughness curve.

Further, a portion 3 of the mask portion on the side in contact with the substrate on which a pattern is to be formed is in contact with the substrate except for a portion having a shape with a gap. Therefore, it is preferable that embossing is performed as shown in FIG. This embossing is preferably such that the contact area with the substrate is 50 to 75%. The embossing method / shape may be any method / shape as long as scratches are unlikely to occur. In the example of the embossing pattern in FIG. 5, the diameter portion is processed to be convex and the other portions are processed to be concave.

Of course, these configurations can be used in combination.

The mask of the present invention can be used as a mask for patterning and forming a conductive thin film. The conductive thin film is made of, for example, a single or mixture of indium oxide, tin oxide, a mixture of indium oxide and tin oxide (hereinafter, referred to as ITO), gold, silver, copper, aluminum, palladium, platinum, or a laminate. The thickness is preferably from 10 Å to 5000 Å.

The method of bringing the substrate and the mask into close contact during patterning is not limited, and any method such as a method using a clip or a magnet can be adopted.

[0025]

Next, the present invention will be specifically described based on examples.

Comparative Example 1 A 0.7 mm-thick non-alkali glass substrate (7059 manufactured by Corning Incorporated) was subjected to black matrix processing with a resin-based light-shielding agent, and red, green, and blue 3
A laminated composite substrate having a color filter function (400
6 and FIG. 7 by using a nickel-iron alloy mask (42 alloy, 400 mm) as shown in FIGS.
× 500mm × thickness (D) 0.25mmt, processing angle R =
0.004 mm, center line surface roughness Ra = 0.05 μm, without embossing). The mask was superimposed on the surface of the substrate and clipped, and ITO sputtering was performed at a substrate temperature of 240 ° C. and a film thickness of 1400 angstroms. The transparent conductive film thus obtained has a transmittance (λ = 4).
96%, Y value at 00 to 700 nm, surface electric resistance value 15
Ω / □. As a result of the visual inspection of this film, defects due to scratches and sparks occurred frequently at the mask boundary. In addition, since the portion other than the opening of the mask is in full contact with the substrate, a scratch defect occurs on the protective film other than the mask opening, and in a severe case, a defect occurs in which a part of the protective film is peeled off. Was.

6 and 7 except that the thickness was changed.
The same nickel-iron alloy plate having a thickness of 0.5 mm (42 alloy, 400 mm × 500 mm × 0.50 mm thick) shown in FIG.
mmt, processing angle R = 0.005mm, center line surface roughness R
a = 0.06 μm, without embossing), and as a result of repeatedly forming an ITO conductive film in the same manner as described above using a mask manufactured as described above, the layer was repeatedly laminated and adhered to the mask after the number of repetitions exceeded 20 times. The peeling of the ITO film started to occur, and there was a defect of an ITO pinhole (ITO missing). In addition, defects due to scratches and sparks frequently occurred.

Comparative Example 1 is intended to be a content that does not satisfy the requirements of Claim 1.

Content of Claim 1: R = R at the corner of the mask
It is characterized by having a roundness of 0.01 to 0.1 mm.

On the other hand, in Comparative Example 1, the processing angle R of the mask was
= 0.004, 0.005 mm (a mask that does not actively have a rounded shape) is used as an example where defects frequently occur at the mask boundary. Of course, claims 2-4 are the same. However, the requirements of claim 5 are satisfied.

Example 1 As in Comparative Example 1, a 0.50 mm-thick nickel film was formed on a laminated composite substrate having a color filter function by sputtering to form an ITO transparent conductive film by patterning.
As shown in FIGS. 1 and 2, a gap T is formed at the boundary of the pattern in contact with the substrate with an iron alloy plate (42 alloy).
After providing a step of 75 mm to the depth outer peripheral part of 3 mm, the mask is immersed in a mixed etching solution composed of nitric acid, ferric chloride and water, and the whole surface is etched. All corners of the mask are circles of R = 0.02 mm. The taste is provided, and a portion 2 of the mask opposite to the side in contact with the substrate has a center line average roughness: Ra =
A 0.5 μm mask was superimposed on the surface, stopped using both a clip and a magnet, and sputtering was performed at a substrate temperature of 140 ° C. and a thickness of 1400 Å of ITO.
The transparent conductive film thus obtained has a transmittance (λ = 400 to
95% of Y value at 700 nm), surface electric resistance value 16Ω / □
Met. As a result of the visual inspection of this film, no scratch was generated at the boundary of the mask. However, since the mask portion other than the space provided was in contact with the substrate, there was a flaw on the protective film, and in the worst case, there was a problem that a part of the protective film was peeled off. In addition, the gap of 0.75 mm and all corners are rounded with R = 0.02 mm to insulate between the conductive film and the mask on the substrate. Did not. In addition, ITO
As a result of repeatedly forming the conductive film, the number of repetitions was 10
Even after 0 times, no peeling of the ITO film deposited on the mask occurred.

On the other hand, as a result of an appearance inspection of an ITO conductive film formed by a method similar to the above using a mask provided with a step of 0.20 mm to a depth of 3 mm in order to form a gap with the same mask as the above, There were no defects due to scratches or sparks at the boundary, but there was a defect that the entire boundary bleeds with a width of about 0.2 mm.

Example 2 In the same manner as in Comparative Example 1, an ITO transparent conductive film was formed on a laminated composite substrate having a color filter function by sputtering to form a mask, as shown in FIG.
In a nickel-iron alloy plate (42 alloy) having a thickness of m, a gap that does not make contact with the substrate is provided with a step of 0.075 mm to an opening depth of 3 mm, and all corners of the mask are R =
A roundness of 0.02 mm is provided, and a portion 2 of the mask opposite to the side in contact with the substrate has a center line average roughness of Ra = 0.5 μm.
In order to eliminate scratches on the protective film, the mask portion 3 on the side in contact with the substrate, excluding the gap, is embossed so that the contact area with the substrate excluding the opening is 58% as shown in FIG. The mask is superimposed on the surface and stopped by using both the clip and the magnet.
Sputtering was performed at 00 angstrom. The transparent conductive film thus obtained has a transmittance (λ = 400 to 70).
(Y value at 0 nm) was 95%, and the surface electric resistance was 16Ω / □. As a result of the visual inspection of this film, no scratch was generated at the boundary of the mask. In addition, no bleeding defect occurred. In addition, there was no defect caused by the spark. Also, the occurrence of scratch defects on the protective film was very small.

Using this mask, 100 times of repeated use was conducted in order to examine the heat distortion due to long-term use and the durability of the ITO film deposited on the mask, such as peeling, but good results were obtained without any problem. I got

[0035]

According to the present invention, the following excellent effects can be obtained.

(1) There is no defect that the boundary of the pattern is flawed by the heating of the substrate during the patterning due to the difference in the thermal expansion coefficient between the substrate and the mask material.

(2) Since all corners of the mask are rounded, there is no disadvantage that scratches and sparks occur.

(3) Since the surface of the portion opposite to the side in contact with the substrate is roughened, the conductive film deposited on the mask is less likely to be peeled off, and the disadvantage of generating pinholes (missing) is eliminated.

(4) Embossing is performed on the portion of the mask portion on the side in contact with the substrate except for the gap, so that the defect that the protective film is scratched is reduced.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating an example of a patterning mask of the present invention used in Example 1. FIG.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a plan view showing an example of a patterning mask of the present invention used in Embodiment 2.

FIG. 4 is a sectional view taken along the line AA of FIG. 3;

FIG. 5 is an embossed pattern diagram showing an example of a patterning mask of the present invention used in Example 2.

FIG. 6 is a plan view of a conventional patterning mask used in Comparative Example 1.

FIG. 7 is a sectional view taken along the line AA of FIG. 6; Corrected drawings will be sent separately.

[Explanation of symbols]

1: Mask 2: Part of mask opposite to substrate contact side 3: Mask part of substrate contact side T: Mask gap Ra: Average of center line of mask opposite to substrate contact side Roughness R: Roundness of the corner of the mask

Claims (5)

[Claims] 1. A mask for forming a pattern on a substrate, wherein R = 0.01 to 0.1 m at a corner of the mask.
A conductive film patterning mask characterized by having a roundness of m. 2. The conductive film patterning mask according to claim 1, wherein the rounding of the corner portion of the mask is performed by immersing the mask in an etchant after the pattern processing. 3. The mask according to claim 1, wherein a portion of the mask opposite to the side in contact with the substrate has a center line average roughness Ra of 0.1 to 5.0 μm. Mask for patterning a conductive film. 4. A mask for forming a pattern on a substrate, wherein a portion of the mask portion on the side in contact with the substrate on which the pattern is formed has a shape with a gap not in contact with the substrate. 4. An embossing process in which a contact area with the substrate except for a gap between the substrate and the mask is 50 to 75% in a contact area with the substrate.
The conductive film patterning mask according to any one of the above. 5. The conductive film patterning mask according to claim 1, wherein the mask is used to pattern and form a conductive thin film of 10 to 5000 angstroms.