JP2000313179A - Metal mask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal mask which can perform stable printing by forming a stepped part formed on the outside of a fine pore pattern for good snapping-off. SOLUTION: The metal mask 1 has numerous fine pores in a metal substrate 2, one of the surfaces 3 of which is specularly finished. Since one of the surfaces of the metal substrate 2 is specularly finished, the aperture edge part 6 of the opening of the fine pore 5 is uniformly formed, hence no irregularities. Further, the specular surface side is used as a face to be brought into contact with a member to be masked, so that an elaborate masking work is performed. Besides, stepped parts 10 are formed in a groove fashion on the outside of the fine pores 5 in such a way that the fine pores 5 are surrounded. Thus it is possible to facilitate the snapping-off of a printing plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an improvement in a metal mask for performing stable printing.

[0002]

2. Description of the Related Art In a metal mask, a fine hole has a small diameter, and a smaller pitch allows a finer pattern to be formed. However, when a large number of fine holes are densely formed, the surface of the metal mask is not rough and smooth, so the shape of the corners of the opening edge is not uniform, and irregularities are formed, so that it is difficult to mask accurately. is there. Therefore, the present applicant disclosed in Japanese Patent Application Laid-Open No. 10-129140 that the metal substrate surface should be smooth (mirror surface) in order to make the edge of the fine hole on the side that comes into contact with the member to be masked sharp. We have proposed a finished metal mask and have achieved considerable results in solving the above disadvantages. However, when the fine holes are densely formed, there is a disadvantage that the separation between the substrate to be printed and the metal mask during printing is poor and printing is not stable.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its main problem is that a step is formed outside a pattern of fine holes to improve separation of a plate and to stabilize printing. Printing is performed.

[0004]

According to a first aspect of the present invention, there is provided a metal mask in which a large number of fine holes are formed in a metal substrate as a pattern. In addition, a technical measure is taken such that the substrate to be processed and the metal mask are easily separated from each other during processing such as printing. Also,
According to the second aspect of the present invention, one surface of the metal substrate is formed into a smooth surface (mirror surface) so as to be sharp so as not to cause unevenness at the edge of the opening of the fine hole to be a pattern, and to cover the smooth surface side. Technical measures are taken to make the surface contact with the mask member. According to the third aspect of the present invention, there is provided a technical means in which the step is formed so as to surround the outer periphery of one fine hole or a plurality of aggregated fine holes. According to the fourth aspect of the present invention, there is provided a technical means in which the metal mask comprises a shielding mask, a solder cream printing mask, a conductive paste printing mask, and an ultra-precision processing part.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the metal mask of the present invention will be described below with reference to the drawings. The metal mask 1 shown in FIG. 1 has a configuration in which a metal substrate 2 has a large number of fine holes 5 and one surface 3 of the metal substrate 2 is mirror-finished. In this embodiment, the mirror finish is a glossy surface having a surface roughness of 0.5 μm or less. In the present invention, however, the substance that has entered the micropores 5 simply exceeds the opening surface of the micropores 5. What is necessary is that the material has a smoothness that can be closely adhered to the surface to be processed so as to function as a mask that largely leaks to the surface to be processed.

As described above, since one surface of the metal substrate 2 is a mirror surface, the edge 6 of the opening of the fine hole 5 is uniformly formed to be sharp, so that no irregularities are generated. Since the mirror side is used as a surface to be brought into contact with the member to be masked, fine mask printing can be performed. A step portion 10 formed by half etching is formed in a groove shape on the front surface 3 side so as to surround the outside of the fine hole 5. In the illustrated example, a step portion 10 composed of a groove is formed so as to surround one micro hole 5. The step portion 10 may have an annular groove shape so as to surround the outer periphery of one fine hole 5.

The step portion 10 may be formed at a location where a plurality of fine holes 5 are gathered, and a groove-shaped step portion 10 may be formed so as to surround the outside along the outer periphery. The step portion 10 shown in FIG. 4 and FIG. 5 forms a step portion in a lattice shape crossing vertically and horizontally,
The configuration is such that a pattern formed of a set of a predetermined number of fine holes 5 is arranged at a portion surrounded by each lattice. As the arrangement shape of the step portion 5, an appropriate shape composed of a straight line, a curve, or a combination thereof can be used as long as the shape surrounds the outside of the fine hole 5 in a series.

Since the step portion 10 is formed in a groove shape along the outer periphery of the fine hole 5 as described above, the step portion 10 becomes a gap and forms a non-contact portion with the substrate to be printed. As a result, separation of the printing plate from the substrate and the mask can be performed reliably and easily, and stable printing can be performed. Here, the step portion 10 in the illustrated example is 2 to 2 from the mirror-finished surface.
Although it has a shape depressed by 3 microns, in the present invention, the depth of the step portion 5 is not particularly limited to the above-described embodiment, but may be any through hole.

The metal mask 1 shown in FIG. 2 shows a different embodiment in which the fine holes 5 are tapered, and has a large number of fine holes 5 in the metal substrate 2. Reference numeral 5 denotes a configuration in which the inner wall cross section is formed in a tapered shape, and one surface 3a of the metal substrate 2 on which the large-diameter side opening 6a appears is mirror-finished.

In this case, the dimensions of each part are the same as those of the above-described embodiment, and the opening taper angle θ is preferably within 10 degrees. By providing the taper, for example, the printability of cream solder can be improved. That is, the taper can be formed along the shape of the bump, so that the filling property and the removability can be improved, and the occurrence of blurring and bridges can be reduced. Further, in the present invention, the surface where the small diameter side of the fine hole 5 appears may be mirror-finished with the taper of the fine hole 5 being reversed (see FIG. 3).

The metal mask is used as a shielding mask such as an optical mask used in a semiconductor process, which requires a large amount of continuous fine hole patterns, or as a cream solder printing mask such as a solder bump printing mask on a wafer. It can be used for ultra-precision processed parts such as solder cream print masks, conductive paste print masks, and microelectronic parts (for example, rotating plates of rotation sensors). Further, in the embodiment, the case where the surface of the metal mask is formed to have a mirror finish is illustrated. However, the present invention is not limited to the case where the surface is a horizontal surface and the mirror finish is required. In addition, the present invention can be applied not only to printing but also to various types of processing, and it is possible to improve separation between a substrate to be processed, a metal mask, and a plate. In addition, the manufacturing method and application are not particularly limited, and it goes without saying that various design changes can be made without departing from the scope of the present invention.

[0012]

According to the present invention, since the step is formed in a groove shape so as to surround the fine hole, it is possible to perform stable printing or the like by improving separation of the plate from the substrate to be processed. .

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a metal mask according to a first embodiment.

FIG. 2 is a partial cross-sectional view of another embodiment in which the taper of the fine hole has a mirror surface on the large diameter side.

FIG. 3 is a partial cross-sectional view of another embodiment in which the taper of the fine hole has a mirror surface on the small diameter side.

FIG. 4 is a partial cross-sectional view of an embodiment in which grooves of a step portion are formed in a lattice shape.

FIG. 5 is a plan view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Metal mask 2 ... Metal substrate 3, 3a ... Mirror-finished surface 5 ... Micropore 6 ... Edge 10 ... Step

Claims (4)

[Claims] 1. A metal mask in which a number of fine holes are formed as a pattern in a metal substrate, a step portion is formed by half-etching outside the pattern, and the substrate to be processed is separated from the metal mask during processing such as printing. A metal mask characterized by ease of use. 2. One surface of a metal substrate is made a smooth surface (mirror surface).
2. The method according to claim 1, wherein the edge of the opening of the fine hole to be a pattern is formed in a sharp shape so as not to cause unevenness, and the smooth surface side is a surface to be brought into contact with the masked member.
The metal mask described in 1. 3. The metal mask according to claim 1, wherein the step portion is formed so as to surround the outer periphery of one fine hole or a plurality of aggregated fine holes. 4. The metal mask according to claim 1, wherein the metal mask comprises a shielding mask, a solder cream printing mask, a conductive paste printing mask, and a super-precision processed part.