KR102474454B1 - Deposition mask manufacturing method and deposition mask - Google Patents

Abstract

Provided is a method of manufacturing a deposition mask having through holes having a complicated shape by using a plating process. A method for manufacturing a deposition mask includes a first film forming step of forming a first metal layer having first openings formed in a predetermined pattern on an insulating substrate, and a second metal layer having second openings communicating with the first openings. It is provided with the 2nd film-forming process to form on a metal layer. The second film formation step includes a resist formation step of forming a resist pattern on the substrate and the first metal layer with a predetermined gap therebetween, and a plating treatment step of depositing a second metal layer on the first metal layer in the gap between the resist patterns contains The resist forming step is performed so that the first opening of the first metal layer is covered with the resist pattern and the gap between the resist patterns is located on the first metal layer.

Description

Deposition mask manufacturing method and deposition mask

The present invention relates to a method for manufacturing a deposition mask having a plurality of through holes formed thereon by plating. Further, the present invention relates to a deposition mask.

BACKGROUND ART [0002] In recent years, display devices used in portable devices such as smart phones and tablet PCs are required to be highly precise, for example, to have a pixel density of 400 ppi or more. In addition, even in a portable device, demand for ultra full high-vision is increasing, and in this case, the pixel density of the display device is required to be 800 ppi or more, for example.

Because of good responsiveness, low power consumption and high contrast, organic EL display devices are attracting attention. As a method of forming pixels of an organic EL display device, a method of forming pixels in a desired pattern using a deposition mask including through holes arranged in a desired pattern is known. Specifically, first, a deposition mask is brought into close contact with a substrate for an organic EL display device, and then both the deposition mask and the substrate adhered are put into a deposition apparatus to deposit an organic material or the like. In this case, in order to precisely manufacture an organic EL display device having a high pixel density, it is required to precisely reproduce the position and shape of the through hole of the deposition mask according to design or to reduce the thickness of the deposition mask.

As a method for manufacturing a deposition mask, a method of forming a through hole in a metal plate by etching using a photolithography technique is known, for example, as disclosed in Patent Literature 1. For example, first, a first resist pattern is formed on the first surface of the metal plate, and then a second resist pattern is formed on the second surface of the metal plate. Subsequently, a region not covered by the first resist pattern of the first surface of the metal plate is etched to form a first concave portion in the first surface of the metal plate. Thereafter, a region of the second surface of the metal plate not covered by the second resist pattern is etched to form a second concave portion in the second surface of the metal plate. At this time, by performing etching so that the first concave portion and the second concave portion communicate with each other, a through hole penetrating the metal plate can be formed. In addition, the first surface of the metal plate refers to a surface constituting the first surface of the deposition mask facing the organic EL display substrate (hereinafter also referred to as an organic EL substrate). In addition, the second surface of the metal plate refers to a surface constituting the second surface of a deposition mask located on the side of an evaporation source such as a crucible holding an evaporation material.

Incidentally, in the etching step, the erosion of the metal plate proceeds not only in the normal direction of the metal plate, but also in the direction along the plate surface of the metal plate. That is, even in a portion of the metal plate covered by the resist pattern, erosion of the metal plate occurs at least partially. Therefore, in the method using etching, it is impossible to form through-holes in the metal plate according to the resist pattern, and for this reason, it is difficult to precisely reproduce the shape of the through-holes of the deposition mask according to the design. In addition, when the through hole has a complicated shape, such as when the dimensions of the through hole are different on the first surface side and the second surface side of the metal surface, the design reproducibility of the through hole of the actually produced deposition mask is further deteriorated. throw away

Further, when a deposition mask is manufactured using etching, the degree of erosion of the metal plate in the direction along the plate surface of the metal plate changes depending on the length of time until the etching in the normal direction of the metal plate is completed. . That is, depending on the thickness of the metal plate, the shape of the through hole varies. For this reason, it is not easy to precisely reproduce both the thickness of the metal plate, that is, the thickness of the deposition mask, and the shape of the through hole.

As a method of manufacturing a deposition mask, a method of manufacturing a deposition mask using a plating process is known, as disclosed in Patent Literature 2, for example, in addition to the method using the above-mentioned etching. For example, in the method described in Patent Literature 2, first, a conductive template is prepared. Next, a resist pattern is formed on the template plate with a predetermined gap therebetween. This resist pattern is provided at the position where the through hole of the deposition mask is to be formed. Thereafter, a plating solution is supplied to the gaps between the resist patterns, and a metal layer is deposited on the template plate by an electrolytic plating process. Thereafter, by separating the metal layer from the model plate, a deposition mask having a plurality of through holes can be obtained.

According to the method of manufacturing a deposition mask using a plating process, a through hole may be formed in a metal plate according to a resist pattern. That is, the position or shape of the through hole of the deposition mask can be accurately reproduced according to the design. Further, by adjusting the duration of the plating process, the thickness of the deposition mask can be set independently of the position and shape of the through hole of the deposition mask.

Japanese Patent No. 5382259 Japanese Unexamined Patent Publication No. 2001-234385

In order to suppress the occurrence of shadows in the deposition process or to precisely control the area, shape and thickness of the deposition material attached to the organic EL substrate, it is necessary that the shape and size of the through hole of the deposition mask change depending on the position. There are times when it becomes necessary. For example, Patent Document 1 described above discloses an example in which the opening size of the through hole on the first surface side of the deposition mask is smaller than the opening size of the through hole on the second surface side. However, with the method described in Patent Literature 2, it is impossible to manufacture a deposition mask having through holes having such a complicated shape.

The present invention has been made in view of these problems, and an object of the present invention is to provide a method for manufacturing a deposition mask having through holes having a complex shape by using a plating process.

The present invention is a deposition mask manufacturing method for manufacturing a deposition mask having a plurality of through holes, comprising: a first film forming step of forming a first metal layer having first openings in a predetermined pattern on an insulating substrate; A second film forming step of forming a second metal layer having a second opening communicating with the opening on the first metal layer, and a separation step of separating the combination of the first metal layer and the second metal layer from the substrate, The second film forming step includes a resist formation step of forming a resist pattern on the substrate and on the first metal layer with a predetermined gap therebetween, and forming a resist pattern on the first metal layer in the gap between the resist patterns. A plating treatment step of depositing a metal layer, wherein the resist formation step includes covering the first opening of the first metal layer with the resist pattern and the gap of the resist pattern being located on the first metal layer It is a method of manufacturing a deposition mask, which is carried out to do so.

In the method of manufacturing a deposition mask according to the present invention, a conductive pattern having a pattern corresponding to the first metal layer is formed on the substrate, and the first film forming step comprises forming the first metal layer on the conductive pattern. You may include the plating process process which makes it precipitate.

In the method for manufacturing a deposition mask according to the present invention, the plating treatment step of the first film forming step includes an electroplating treatment step of depositing the first metal layer on the conductive pattern by flowing a current through the conductive pattern. You can do it.

In the first film forming step, the first metal layer is formed anywhere on a portion overlapping the conductive pattern and a portion not overlapping the conductive pattern when viewed along a normal direction of the substrate, and in the separation step , A concave portion having a shape corresponding to the conductive pattern may be formed in the first metal layer separated from the substrate and the conductive pattern.

In the method for manufacturing a deposition mask according to the present invention, the plating treatment step of the second film forming step comprises an electrolytic plating treatment step of depositing the second metal layer on the first metal layer by flowing a current through the first metal layer. may contain

The present invention is a deposition mask having a plurality of through holes extending from a first surface to a second surface, including a metal layer in which the through holes are formed in a predetermined pattern, and a portion of the through holes positioned on the first surface is formed. When the through hole is referred to as a first opening and a portion of the through hole located on the second surface is referred to as a second opening, the through hole is the first opening when the deposition mask is viewed along the normal direction of the deposition mask. A deposition mask in which an outline of two openings surrounds an outline of the first opening, and a concave portion is formed on the first surface.

In the deposition mask according to the present invention, the width of the portion of the first surface where the concave portion is not formed may be in the range of 0.5 to 5.0 μm.

In the deposition mask according to the present invention, the metal layer may include a first metal layer formed with the first opening and the concave portion, and a second metal layer stacked on the first metal layer and formed with the second opening.

In the deposition mask according to the present invention, when the deposition mask is viewed along a normal direction of the deposition mask, the concave portion formed in the first metal layer outlines a connection portion where the first metal layer and the second metal layer are connected. may surround

In the deposition mask according to the present invention, the metal layer may be a plating layer.

In the deposition mask and method for manufacturing the same according to the present invention, the thickness of a portion of the first metal layer connected to the second metal layer may be 5 μm or less.

In the deposition mask and manufacturing method thereof according to the present invention, the thickness of the second metal layer is in the range of 3 to 50 μm, more preferably in the range of 3 to 30 μm, and still more preferably in the range of 3 to 25 μm. may be within the range.

A method for manufacturing a deposition mask according to the present invention includes a first film forming step of forming a first metal layer having first openings formed in a predetermined pattern on an insulating substrate, and a second opening having second openings communicating with the first openings. A 2nd film-forming process of forming a metal layer on a 1st metal layer is provided. The second film formation step includes a resist formation step of forming a resist pattern on the substrate and the first metal layer with a predetermined gap therebetween, and a plating treatment step of depositing a second metal layer on the first metal layer in the gap between the resist patterns contains Therefore, both the shape defined by the first opening of the first metal layer and the shape defined by the second opening of the second metal layer can be given to the through hole of the deposition mask. Thus, a through hole having a complicated shape can be precisely formed. In addition, by forming the second metal layer using a plating process, the thickness of the deposition mask can be arbitrarily set independently of the shape of the through hole.

1 is a schematic plan view showing an example of a deposition mask device including a deposition mask in an embodiment of the present invention.
FIG. 2 is a diagram for explaining a method of depositing using the deposition mask device shown in FIG. 1 .
FIG. 3 is a partial plan view showing the deposition mask shown in FIG. 1 .
Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3;
FIG. 5 is an enlarged cross-sectional view of a part of the first metal layer and the second metal layer of the deposition mask shown in FIG. 4 .
6 is a cross-sectional view showing a patterned substrate including a conductive pattern formed on the substrate.
7A is a cross-sectional view showing a first plating treatment step of depositing a first metal layer on a conductive pattern.
Fig. 7B is a plan view showing the first metal layer of Fig. 7A.
8A is a cross-sectional view showing a resist formation step of forming a resist pattern on the pattern substrate and on the first metal layer.
Fig. 8B is a plan view showing the resist pattern of Fig. 8A.
9 is a cross-sectional view showing a second plating treatment step of depositing a second metal layer on the first metal layer.
10 is a diagram showing a removal process of removing a resist pattern.
11A is a diagram showing a separation process for separating the combination of the first metal layer and the second metal layer from the patterned substrate.
Fig. 11B is a plan view showing the case where the deposition mask of Fig. 11A is viewed from the second surface side.
12 is a cross-sectional view showing a first film forming step of forming a first metal layer on a substrate in a first modified example of the embodiment of the present invention.
FIG. 13 is a cross-sectional view showing a second plating treatment step of depositing a second metal layer on the first metal layer shown in FIG. 12 .
14 is a cross-sectional view showing a deposition mask in a first modified example of the embodiment of the present invention.
Fig. 15 is a cross-sectional view showing a resist formation step of forming a resist pattern on the pattern substrate and on the first metal layer in the second modified example of the embodiment of the present invention.
16 is a cross-sectional view showing a second plating treatment step of depositing a second metal layer on the first metal layer in a second modification of the embodiment of the present invention.
17 is a cross-sectional view showing a deposition mask in a second modified example of the embodiment of the present invention.
18 is a diagram showing a modified example of a deposition mask device including a deposition mask.
19 is a cross-sectional view showing a deposition mask in which concave portions are specified.
FIG. 20 is an enlarged cross-sectional view of the deposition mask shown in FIG. 19 .
21 is a plan view showing the case where the deposition mask is viewed from the first surface side.
22A is a diagram showing a position adjustment step of adjusting the position of the deposition mask in the surface direction of the organic EL substrate.
FIG. 22B is a diagram showing an adhesion step of adhering the deposition mask to the organic EL substrate.
22C is a diagram showing an example in which the concave surface of the concave portion of the deposition mask adheres to the organic EL substrate.
23 is a plan view showing a modified example of arrangement of a plurality of through holes of the deposition mask.
24A is a diagram for explaining a method for manufacturing a patterned substrate.
24B is a diagram for explaining a method of manufacturing a pattern substrate.
24C is a diagram for explaining a method of manufacturing a patterned substrate.
24D is a diagram for explaining a method for manufacturing a patterned substrate.
25 is an enlarged cross-sectional view of an example of a conductive pattern on a patterned substrate.
FIG. 26 is an enlarged cross-sectional view of a deposition mask obtained when the first film forming step is performed using the patterned substrate shown in FIG. 25 .
Fig. 27 is an enlarged cross-sectional view of another example of a conductive pattern on a patterned substrate.
FIG. 28 is an enlarged cross-sectional view of a deposition mask obtained when the first film forming step is performed using the patterned substrate shown in FIG. 27 .

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of this invention is described with reference to drawings. In addition, in the drawings attached to this specification, for convenience of illustration and understanding, the scale and size ratio of length and width are appropriately changed from those of the real thing and exaggerated.

1 to 28 are diagrams for explaining an embodiment according to the present invention and a modified example thereof. In the following embodiments and modifications thereof, a method for manufacturing a deposition mask used for patterning an organic material on a substrate into a desired pattern when manufacturing an organic EL display device will be described as an example. However, it is not limited to these applications, and the present invention can be applied to a method for manufacturing a deposition mask used for various purposes.

Also, in this specification, the terms "plate", "sheet", and "film" are not distinguished from each other based only on differences in names. For example, "plate" is a concept that includes members that can be called sheets and films.

Further, "plate surface (sheet surface, film surface)" refers to the target plate-like member (sheet-like member, film-like member) when the target plate-like (sheet-like, film-like) member is viewed as a whole and as a whole. Points to the plane coincident with the direction of the plane. In addition, the "normal direction" used for a plate-like (sheet-like, film-like) member refers to the normal direction with respect to the plate surface (sheet surface, film surface) of the member.

In addition, terms used in this specification, such as "parallel", "orthogonal", "equal", "equivalent", lengths, and angles that specify shapes, geometrical conditions, and physical properties, and their degrees, for example , and the values of the physical characteristics, etc., will be analyzed including the range to which the same function can be expected without being bound by the strict meaning.

(deposition mask device)

First, an example of a deposition mask device including a deposition mask will be described with reference to FIGS. 1 to 4 . Here, FIG. 1 is a plan view showing an example of a deposition mask device including a deposition mask, and FIG. 2 is a diagram for explaining a method of using the deposition mask device shown in FIG. 1 . FIG. 3 is a plan view showing the deposition mask from the first surface side, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3 .

The deposition mask apparatus 10 shown in FIGS. 1 and 2 includes a plurality of deposition masks 20 having a substantially rectangular shape when viewed from a plan view, and a frame installed at peripheral edges of the plurality of deposition masks 20 ( 15) is provided. A plurality of through holes 25 penetrating the deposition mask 20 are formed in each deposition mask 20 . As shown in FIG. 2, the deposition mask device 10 is supported in the deposition device 90 so that the deposition mask 20 faces the lower surface of the substrate to be deposited, for example, the organic EL substrate 92. and is used for deposition of a deposition material on the organic EL substrate 92.

Inside the deposition apparatus 90, the deposition mask 20 and the organic EL substrate 92 come into close contact with each other due to magnetic force from a magnet (not shown). Inside the deposition apparatus 90, below the deposition mask apparatus 10, a crucible 94 for accommodating an evaporation material (an organic light emitting material as an example) 98, and a heater 96 for heating the crucible 94 ) is placed. The evaporation material 98 in the crucible 94 vaporizes or sublimes by heating from the heater 96 and adheres to the surface of the organic EL substrate 92 . As described above, a plurality of through holes 25 are formed in the deposition mask 20, and the evaporation material 98 is adhered to the organic EL substrate 92 through the through holes 25. As a result, the deposition material 98 is formed on the surface of the organic EL substrate 92 in a desired pattern corresponding to the position of the through hole 25 of the deposition mask 20 . In Fig. 2, among the surfaces of the deposition mask 20, a surface facing the organic EL substrate 92 during the deposition process (hereinafter also referred to as a first surface) is denoted by reference numeral 20a. Among the surfaces of the deposition mask 20, a surface (hereinafter also referred to as a second surface) located on the side of the deposition source of the deposition material 98 (here, the crucible 94) is indicated by reference numeral 20b.

As described above, in this embodiment, the through holes 25 are arranged in a predetermined pattern in each effective region 22 . Further, when color display is desired, the deposition mask 20 (deposition mask device 10) and the organic EL substrate 92 are relatively moved little by little along the arrangement direction of the through holes 25 (one direction described above). , the organic light emitting material for red, the organic light emitting material for green, and the organic light emitting material for blue may be sequentially deposited. Alternatively, each evaporator equipped with the deposition mask 20 corresponding to each color may be prepared, and the organic EL substrate 92 may be sequentially introduced into each evaporator.

Further, the frame 15 of the deposition mask device 10 is provided on the peripheral edge of the rectangular deposition mask 20 . The frame 15 holds the deposition mask 20 attached so that the deposition mask 20 does not warp. The deposition mask 20 and the frame 15 are fixed to each other by, for example, spot welding.

By the way, the vapor deposition process may be performed inside the vapor deposition apparatus 90 in a high-temperature atmosphere. In this case, during the deposition process, the deposition mask 20, the frame 15, and the organic EL substrate 92 held inside the deposition apparatus 90 are also heated. At this time, the deposition mask 20, the frame 15, and the organic EL substrate 92 exhibit dimensional change behavior based on their respective coefficients of thermal expansion. In this case, if the thermal expansion coefficients of the deposition mask 20 or frame 15 and the organic EL substrate 92 differ greatly, positional displacement due to a difference in dimensional change between them occurs, and as a result, the organic EL substrate ( 92) The dimensional accuracy and positional accuracy of the evaporation material adhering thereon deteriorate. In order to solve such a problem, it is preferable that the thermal expansion coefficient of the deposition mask 20 and the frame 15 be equal to the thermal expansion coefficient of the organic EL substrate 92 . For example, when a glass substrate is used as the organic EL substrate 92, an iron alloy containing nickel can be used as a main material of the deposition mask 20 and the frame 15. For example, an iron alloy such as an invar material containing 34 to 38% by mass of nickel, a super invar material that further contains cobalt in addition to 30 to 34% by mass of nickel, and an iron alloy containing 38 to 54% by mass of nickel A low thermal expansion Fe-Ni-based plating alloy or the like can be used as a material for the first metal layer 32 and the second metal layer 37 constituting the deposition mask 20, which will be described later. In addition, in this specification, the numerical range expressed by the symbol "to (-)" includes the numerical values placed before and after the symbol "to (-)". For example, the numerical range defined by the expression "34-38 mass %" is the same as the numerical range defined by the expression "34 mass % or more and 38 mass % or less".

In addition, when the temperature of the deposition mask 20, the frame 15, and the organic EL substrate 92 does not reach a high temperature during the deposition process, the thermal expansion coefficient of the deposition mask 20 and the frame 15 is reduced by the organic EL substrate 92. It is not particularly necessary to set the value equal to the thermal expansion coefficient of the EL substrate 92. In this case, as the material of the first metal layer 32 and the second metal layer 37 described later constituting the deposition mask 20, various materials other than the above-mentioned iron alloy containing nickel can be used. For example, an iron alloy containing chromium, nickel, a nickel-cobalt alloy, or the like can be used. As the iron alloy containing chromium, for example, an iron alloy called stainless steel can be used.

(deposition mask)

Next, the deposition mask 20 will be described in detail. As shown in Fig. 1, in the present embodiment, the deposition mask 20 has an outline of a substantially rectangular shape in plan view, more precisely, a substantially rectangular shape in plan view. The deposition mask 20 includes an effective area 22 in which through holes 25 are formed in a regular arrangement, and a peripheral area 23 surrounding the effective area 22 . The peripheral area 23 is an area for supporting the effective area 22, and is not an area through which evaporation material intended to be deposited on the substrate passes. For example, in the deposition mask 20 used for depositing the organic light emitting material for an organic EL display device, the effective area 22 is the portion of the organic EL substrate 92 on which the organic light emitting material is deposited to form pixels. It refers to a region within the deposition mask 20 facing the region serving as the display region. However, for various purposes, a through hole or a recess may be formed in the peripheral region 23 . In the example shown in Fig. 1, each effective area 22 has an outline of a substantially rectangular shape in plan view, more precisely, a substantially rectangular shape in plan view. In addition, although not shown, each effective area 22 can have a contour of various shapes depending on the shape of the display area of the organic EL substrate 92 . For example, each effective area 22 may have a circular outline.

In the illustrated example, the plurality of effective regions 22 of the deposition mask 20 are arranged in a line at predetermined intervals along one direction parallel to the longitudinal direction of the deposition mask 20 . In the illustrated example, one effective area 22 corresponds to one organic EL display device. That is, according to the deposition mask apparatus 10 (deposition mask 20) shown in FIG. 1, multi-sided deposition is possible.

As shown in FIG. 3 , in the illustrated example, a plurality of through holes 25 formed in each effective region 22 are formed along two directions orthogonal to each other in the effective region 22, respectively. arranged in pitch. The shape and the like of this through hole 25 will be described in more detail with reference to FIGS. 3 and 4 .

As shown in FIGS. 3 and 4 , the deposition mask 20 includes a metal layer in which a plurality of through holes 25 are formed in a predetermined pattern. The metal layer includes a first metal layer 32 in which first openings 30 are formed in a predetermined pattern, and a second metal layer 37 in which second openings 35 communicating with the first openings 30 are formed. . The second metal layer 37 is disposed on the second surface 20b side of the deposition mask 20 rather than the first metal layer 32 . In the example shown in FIG. 4 , the first metal layer 32 constitutes the first surface 20a of the deposition mask 20, and the second metal layer 37 constitutes the second surface 20b of the deposition mask 20. ) is made up of In addition, in this embodiment, the metal layer is a plating layer produced by a plating process so that it may be mentioned later. For example, the 1st metal layer 32 is a 1st plating layer produced by the 1st plating process process mentioned later, and the 2nd metal layer 37 is the 2nd plating layer produced by the 2nd plating process process mentioned later. to be.

In this embodiment, the through hole 25 penetrating the deposition mask 20 is formed by communicating the first opening 30 and the second opening 35 to each other. In this case, the opening size and opening shape of the through hole 25 on the first surface 20a side of the deposition mask 20 are defined by the first opening 30 of the first metal layer 32 . On the other hand, the opening size and opening shape of the through hole 25 on the second surface 20b side of the deposition mask 20 are defined by the second opening 35 of the second metal layer 37 . In other words, the through hole 25 has both the shape defined by the first opening 30 of the first metal layer 32 and the shape defined by the second opening 35 of the second metal layer 37 This is granted.

As shown in FIG. 3 , the first opening 30 and the second opening 35 constituting the through hole 25 may have a substantially polygonal shape in plan view. Here, an example in which the first opening 30 and the second opening 35 are substantially rectangular, more specifically, substantially square is shown. In addition, although not shown, the 1st opening part 30 and the 2nd opening part 35 may have other substantially polygonal shapes, such as a substantially hexagonal shape and a substantially octagonal shape. In addition, "substantially polygonal shape" is a concept including a shape in which the corners of a polygon are rounded. In addition, although not shown, the 1st opening part 30 and the 2nd opening part 35 may be circular shape. In addition, as long as the second opening 35 has an outline surrounding the first opening 30 in plan view, the shape of the first opening 30 and the shape of the second opening 35 need not be similar. none.

Although not shown, the first opening 30 and the second opening 35 constituting the through hole 25 may have a shape other than a polygonal shape in plan view, for example, a circular shape.

In FIG. 4 , reference numeral 41 denotes a connection portion where the first metal layer 32 and the second metal layer 37 are connected. In addition, in FIG. 4, although the example in which the 1st metal layer 32 and the 2nd metal layer 37 are in contact is shown, it is not limited to this, and between the 1st metal layer 32 and the 2nd metal layer 37 Other layers may be interposed. For example, a catalyst layer for promoting precipitation of the second metal layer 37 on the first metal layer 32 may be provided between the first metal layer 32 and the second metal layer 37 .

FIG. 5 is an enlarged view of a part of the first metal layer 32 and the second metal layer 37 of FIG. 4 . As shown in FIG. 5 , the width M2 of the second metal layer 37 on the second surface 20b of the deposition mask 20 is the width M2 of the first surface 20a of the deposition mask 20. 1 is smaller than the width M1 of the metal layer 32. In other words, the opening size S2 of the through hole 25 (second opening 35) in the second surface 20b is the through hole 25 (first opening ( 30)) is larger than the opening size S1. Advantages of configuring the first metal layer 32 and the second metal layer 37 in this way will be described below.

The evaporation material 98 coming from the side of the second surface 20b of the deposition mask 20 passes through the second opening 35 and the first opening 30 of the through hole 25 in order, and passes through the organic EL substrate. Attached to (92). The area|region to which the evaporation material 98 adheres in the organic electroluminescent substrate 92 is mainly determined by the opening size S1 of the through-hole 25 in the 1st surface 20a, and the opening shape. By the way, as indicated by the arrow L1 directed from the second surface 20b side to the first surface 20a in FIG. 4 , the evaporation material 98 is deposited from the crucible 94 toward the organic EL substrate 92. Not only does it move along the normal direction N of the mask 20, but it also moves in a direction greatly inclined with respect to the normal direction N of the deposition mask 20 in some cases. Here, if the opening size S2 of the through hole 25 on the second surface 20b is the same as the opening size S1 of the through hole 25 on the first surface 20a, the deposition mask 20 Most of the evaporation material 98 moving in a direction greatly inclined with respect to the normal direction N of the second opening of the through hole 25 before reaching the organic EL substrate 92 through the through hole 25. It reaches the wall surface 36 of (35) and adheres thereto. Therefore, in order to increase the efficiency of use of the evaporation material 98, it can be said that it is preferable to increase the opening size S2 of the second opening 35, that is, to reduce the width M2 of the second metal layer 37.

In FIG. 4 , the minimum angle formed by the straight line L1 passing through the end 38 of the second metal layer 37 and the end 33 of the first metal layer 32 with respect to the normal direction N of the deposition mask 20 is , denoted by the symbol θ1. In order to allow the obliquely moving evaporation material 98 to reach the organic EL substrate 92 as much as possible without reaching the wall surface 36 of the second opening 35, it is advantageous to increase the angle θ1. From the aspect of increasing the angle θ1, it is effective to make the width M2 of the second metal layer 37 smaller than the width M1 of the first metal layer 32. Further, as is clear from the drawing, it is also effective to reduce the thickness T1 of the first metal layer 32 or the thickness T2 of the second metal layer 37 from the viewpoint of increasing the angle θ1. Here, "thickness T1 of the 1st metal layer 32" means the thickness in the part connected to the 2nd metal layer 37 among the 1st metal layer 32. In addition, if the width M2 of the second metal layer 37, the thickness T1 of the first metal layer 32, or the thickness T2 of the second metal layer 37 are excessively reduced, the strength of the deposition mask 20 is reduced. Therefore, it is considered that the deposition mask 20 is damaged during transport or use. For example, it is considered that the deposition mask 20 is damaged by the tensile stress applied to the deposition mask 20 when the deposition mask 20 is applied to the frame 15 . Considering these points, it can be said that it is preferable that the dimensions of the first metal layer 32 and the second metal layer 37 are set within the following ranges. Thereby, the angle θ1 described above can be set to, for example, 45° or more.

ㆍWidth M1 of the first metal layer 32: 5 to 25 μm

ㆍWidth M2 of the second metal layer 37: 2 to 20 μm

ㆍThickness T0 of deposition mask 20: 5 to 50 μm

ㆍThickness T1 of the first metal layer 32: 5 μm or less

ㆍThickness T2 of the second metal layer 37: 2 to 50 μm, more preferably 3 to 50 μm, even more preferably 3 to 30 μm, still more preferably 3 to 25 μm

Table 1 shows examples of values of the dimensions of the first metal layer 32 and the second metal layer 37 obtained according to the number of display pixels and the number of display pixels in a 5-inch organic EL display device. Also, "FHD" means Full High Definition, "WQHD" means Wide Quad High Definition, and "UHD" means Ultra High Definition.

Next, the shape of the first metal layer 32 will be described in more detail. For example, as shown by the dotted line in FIG. 5 , when the first metal layer 32 at the end portion 33 has a shape soaring greatly toward the second surface 20b side, the through hole 25 It is considered that most of the evaporation material 98 after passing through the second opening 35 reaches the wall surface 31 of the first metal layer 32 and adheres thereto. In order to suppress the adhesion of the evaporation material 98 to the first metal layer 32 in the vicinity of the end portion 33, as shown in FIG. 5, the first metal layer 32 has the end portion 33 And it is preferable to have a thickness smaller than the thickness T1 in the part connected to the 2nd metal layer 37 among the 1st metal layer 32 in its vicinity. For example, as shown in FIG. 5, the thickness of the first metal layer 32 monotonically decreases from the portion connected to the second metal layer 37 to the end portion 33 of the first metal layer 32, It is desirable to have As described later, the shape of the first metal layer 32 can be realized by forming the first metal layer 32 by plating.

In FIG. 5 , symbol θ2 denotes an angle between the tangent plane L2 of the first metal layer 32 to the wall surface 31 and the normal direction N of the deposition mask 20 at the end portion 33 . In terms of suppressing the deposition material 98 after passing through the second opening 35 of the through hole 25 from adhering to the wall surface 31 of the first metal layer 32, the angle θ2 is set to be greater than 0°. is also valid Preferably, the angle θ2 is 30° or more, more preferably 45° or more. Such an angle θ2 can also be realized by forming the first metal layer 32 by plating treatment. In addition, "wall surface 31" refers to the surface which partitions and forms the 1st opening part 30 among the surfaces of the 1st metal layer 32. Similarly, the above-mentioned "wall surface 36" refers to the surface of the second metal layer 37 that partitions and forms the second opening 35.

(Manufacturing method of vapor deposition mask)

Next, a method of manufacturing the deposition mask 20 having the above structure will be described with reference to FIGS. 6 to 11B.

(First Film Formation Step)

First, the first film forming step of forming the first metal layer 32 in which the first openings 30 are formed in a predetermined pattern on the insulating substrate 51 will be described. First, as shown in FIG. 6 , a pattern substrate 50 having an insulating substrate 51 and a conductive pattern 52 formed on the substrate 51 is prepared. The conductive pattern 52 has a pattern corresponding to the first metal layer 32 . The material constituting the substrate 51 and the thickness of the substrate 51 are not particularly limited as long as they have insulating properties and appropriate strength. For example, as a material constituting the substrate 51, glass, synthetic resin, or the like can be used.

As the material constituting the conductive pattern 52, a material having conductivity such as a metal material or an oxide conductive material is appropriately used. As an example of a metal material, chromium, copper, etc. are mentioned, for example. Preferably, a material having high adhesion to the resist pattern 54 described later is used as a material constituting the conductive pattern 52 . For example, when the resist pattern 54 is produced by patterning what is called a dry film, such as a resist film made of an acrylic photocurable resin, as a material constituting the conductive pattern 52, the dry film is highly It is preferable that copper having adhesion is used.

As will be described later, a first metal layer 32 is formed on the conductive pattern 52 so as to cover the conductive pattern 52, and the first metal layer 32 is separated from the conductive pattern 52 in a subsequent step. . For this reason, on the surface of the first metal layer 32 on the side in contact with the conductive pattern 52, a concave portion corresponding to the thickness of the conductive pattern 52 is usually formed. Considering this point, as long as the conductive pattern 52 has the conductivity necessary for the electroplating process, the thickness of the conductive pattern 52 is preferably smaller. For example, the thickness of the conductive pattern 52 is in the range of 50 to 500 nm.

Subsequently, a first plating treatment step of depositing a first metal layer 32 on the conductive pattern 52 by supplying a first plating solution onto the substrate 51 on which the conductive pattern 52 is formed is performed. For example, the substrate 51 on which the conductive patterns 52 are formed is immersed in a plating bath filled with a first plating solution. Thereby, as shown in FIG. 7A, the 1st metal layer 32 in which the 1st opening part 30 was formed in the predetermined pattern on the pattern substrate 50 can be obtained. 7B is a plan view showing the first metal layer 32 formed on the substrate 51 .

In addition, due to the nature of the plating process, as shown in FIG. 7A , the first metal layer 32 not only overlaps the conductive pattern 52 when viewed along the normal direction of the substrate 51, but also the conductive pattern 52 ) may also be formed in a part that does not overlap. This is because the first metal layer 32 is further deposited on the surface of the first metal layer 32 deposited in the portion overlapping the end portion 53 of the conductive pattern 52 . As a result, as shown in FIG. 7A, the end portion 33 of the first metal layer 32 may be located at a portion that does not overlap the conductive pattern 52 when viewed along the normal direction of the substrate 51. have. On the other hand, the thickness of the 1st metal layer 32 in the edge part 33 becomes smaller than the thickness in the center part as metal precipitation progressed not in the thickness direction but in the plate surface direction of the board|substrate 51. For example, as shown in FIG. 7A, the thickness of the first metal layer 32 monotonically decreases at least partially from the central portion toward the end portion 33 of the first metal layer 32 . As a result, the angle θ2 described above also becomes a value larger than 0°.

In FIG. 7A, the width of a portion of the first metal layer 32 that does not overlap the conductive pattern 52 is indicated by the symbol w. The width w is in the range of 0.5 to 5.0 μm, for example. The size of the conductive pattern 52 is set in consideration of this width w.

As long as it is possible to deposit the first metal layer 32 on the conductive pattern 52, the specific method of the first plating process is not particularly limited. For example, the first plating treatment step may be performed as a so-called electrolytic plating treatment step in which the first metal layer 32 is deposited on the conductive pattern 52 by applying a current through the conductive pattern 52 . Alternatively, the first plating process may be an electroless plating process. Further, when the first plating process is an electroless plating process, an appropriate catalyst layer is formed on the conductive pattern 52 . Even when the electroplating process is performed, a catalyst layer may be formed on the conductive pattern 52 .

Components of the first plating solution to be used are appropriately determined according to characteristics required of the first metal layer 32 . For example, when the first metal layer 32 is formed of an iron alloy containing nickel, a mixed solution of a solution containing a nickel compound and a solution containing an iron compound can be used as the first plating solution. For example, a mixed solution of a solution containing nickel sulfamate and a solution containing iron sulfamate may be used. The plating solution may contain additives such as malonic acid and saccharin.

(Second Film Formation Step)

Subsequently, a second film forming process of forming a second metal layer 37 having a second opening 35 communicating with the first opening 30 is performed on the first metal layer 32 . First, a resist forming step is performed in which a resist pattern 55 is formed on the substrate 51 and the first metal layer 32 of the pattern substrate 50 with a predetermined gap 56 therebetween. 8A and 8B are cross-sectional and plan views showing a resist pattern 55 formed on a substrate 51 . 8A and 8B, in the resist formation step, the first opening 30 of the first metal layer 32 is covered with the resist pattern 55, and the gap 56 of the resist pattern 55 ) is carried out to be located on the first metal layer 32.

An example of a resist formation step will be described below. First, a negative resist film is formed by attaching a dry film on the substrate 51 of the pattern substrate 50 and on the first metal layer 32 . As an example of a dry film, the thing containing acrylic photocurable resin, such as RY3310 by Hitachi Chemical, is mentioned, for example. Next, an exposure mask is prepared so as not to transmit light to a region of the resist film that should be the gap 56, and the exposure mask is placed on the resist film. After that, the exposure mask is sufficiently brought into close contact with the resist film by vacuum adhesion. Also, as the resist film, a positive type may be used. In this case, as an exposure mask, an exposure mask that transmits light to a region to be removed in the resist film is used.

After that, the resist film is exposed through an exposure mask. Further, the resist film is developed to form an image on the exposed resist film. As described above, as shown in FIGS. 8A and 8B, the gap 56 located on the first metal layer 32 is formed, and the resist covering the first opening 30 of the first metal layer 32 A pattern 55 may be formed. Further, in order to bring the resist pattern 55 into tighter contact with the substrate 51 and the first metal layer 32, a heat treatment step of heating the resist pattern 55 may be performed after the developing step.

Subsequently, a second plating treatment step of depositing a second metal layer 37 on the first metal layer 32 by supplying a second plating solution to the gap 56 of the resist pattern 55 is performed. For example, the substrate 51 on which the first metal layer 32 is formed is immersed in a plating bath filled with the second plating solution. As a result, as shown in FIG. 9 , the second metal layer 37 can be formed on the first metal layer 32 .

As long as it is possible to deposit the second metal layer 37 on the first metal layer 32, the specific method of the second plating process is not particularly limited. For example, the second plating treatment step may be performed as a so-called electroplating treatment step in which the second metal layer 37 is deposited on the first metal layer 32 by applying an electric current through the first metal layer 32 . Alternatively, the second plating process may be an electroless plating process. In addition, when the second plating process is an electroless plating process, an appropriate catalyst layer is formed on the first metal layer 32 . Even when the electroplating process is performed, a catalyst layer may be formed on the first metal layer 32 .

As the second plating solution, the same plating solution as the first plating solution described above may be used. Alternatively, a plating solution different from the first plating solution may be used as the second plating solution. When the composition of the first plating solution and the composition of the second plating solution are the same, the composition of the metal constituting the first metal layer 32 and the composition of the metal constituting the second metal layer 37 are also the same.

9 shows an example in which the second plating process continues until the upper surface of the resist pattern 55 and the upper surface of the second metal layer 37 coincide, but it is not limited thereto. The second plating process may be stopped in a state where the upper surface of the second metal layer 37 is located below the upper surface of the resist pattern 55 .

(removal process)

Then, as shown in FIG. 10, a removal process of removing the resist pattern 55 is performed. For example, the resist pattern 55 can be peeled from the substrate 51 and the first metal layer 32 or the second metal layer 37 by using an alkali-based stripping solution.

(separation process)

Subsequently, a separation process of separating the combination of the first metal layer 32 and the second metal layer 37 from the substrate 51 of the pattern substrate 50 is performed. As a result, as shown in FIG. 11A, the first metal layer 32 in which the first openings 30 are formed in a predetermined pattern, and the second openings 35 communicating with the first openings 30 are formed in the second metal layer 32. A deposition mask 20 having a metal layer 37 can be obtained. 11B is a plan view showing the case where the deposition mask 20 is viewed from the side of the second surface 20b.

Hereinafter, an example of the separation process will be described in detail. First, a film formed by coating or the like of an adhesive substance is attached to the combination of the first metal layer 32 and the second metal layer 37 formed on the substrate 51 . Next, the film is removed from the substrate 51 by lifting or winding the film, thereby removing the combination of the first metal layer 32 and the second metal layer 37 from the substrate 51 of the pattern substrate 50. separate The film is then peeled from the combination of first metal layer 32 and second metal layer 37 .

In addition, in the separation process, first, a gap serving as a trigger for separation is formed between the combination of the first metal layer 32 and the second metal layer 37 and the substrate 51, and then air is formed in the gap. may be sprayed, thereby accelerating the separation process.

In addition, as a substance having adhesiveness, you may use a substance which loses adhesiveness by being irradiated with light, such as UV, or by being heated. In this case, after the combination of the first metal layer 32 and the second metal layer 37 is separated from the substrate 51, a step of irradiating light to the film or a step of heating the film is performed. This facilitates the process of peeling the film from the combination of the first metal layer 32 and the second metal layer 37. For example, the film may be peeled off while keeping the combination of the film and the first metal layer 32 and the second metal layer 37 parallel to each other as much as possible. Accordingly, when the film is peeled off, it is possible to suppress the combination of the first metal layer 32 and the second metal layer 37 from being curved, thereby suppressing the deposition mask 20 from being prone to deformation such as bending. can do.

According to the present embodiment, as described above, the deposition mask 20 is formed by supplying the second plating solution to the gap 56 of the resist pattern 55 to deposit the second metal layer 37 on the first metal layer 32. ) is produced. For this reason, in the through hole 25 of the deposition mask 20, the shape defined by the first opening 30 of the first metal layer 32, and the second opening 35 of the second metal layer 37 Both of the shapes defined by can be given. Thus, the through hole 25 having a complex shape can be precisely formed. For example, a through hole 25 capable of increasing the angle θ1 described above can be obtained. In this way, the utilization efficiency of the evaporation material 98 can be increased. In addition, by forming the second metal layer 37 using a plating process, the thickness T0 of the deposition mask 20 can be arbitrarily set independently of the shape of the through hole 25 . For this reason, it is possible to give the deposition mask 20 sufficient strength. Therefore, a high-precision organic EL display device can be manufactured, and the deposition mask 20 with excellent durability can be provided.

In addition, it is possible to apply various changes to the above-described embodiment. Hereinafter, a modified example is demonstrated, referring drawings as needed. In the following description and the drawings used in the following description, the same reference numerals as those used for corresponding parts in the above-described embodiment are used for parts that can be configured in the same way as in the above-described embodiment, Omit duplicate explanations. In addition, when it is clear that the action and effect obtained in the above-mentioned embodiment are also obtained in a modified example, the explanation may be omitted.

(First modified example)

In this embodiment described above, an example in which the first film forming step includes the first plating treatment step of depositing the first metal layer 32 on the conductive pattern 52 of the pattern substrate 50 has been shown. That is, an example in which the first metal layer 32 is formed by plating is shown. However, it is not limited to this, and the 1st metal layer 32 may be formed by other methods.

For example, a substrate 51 having insulating properties is first prepared, and then the first metal layer 32 is formed over the entire surface of the substrate 51 . As a method of forming the first metal layer 32 on the substrate 51, a physical film forming method such as sputtering, a chemical film forming method, or the like can be appropriately used. Thereafter, a resist pattern is formed on a portion of the first metal layer 32 other than the portion where the first opening 30 is to be formed, and then the first metal layer 32 is etched. By patterning the first metal layer 32 in this way, as shown in FIG. 12 , the first metal layer 32 in which the first openings 30 are formed in a predetermined pattern can be formed on the substrate 51 . In this case, it is not necessary that the above-described conductive pattern 52 is formed on the substrate 51 .

Thereafter, by performing the resist formation process and the second plating process described above, as shown in FIG. 13 , the second metal layer 37 formed with the second opening 35 communicating with the first opening 30 is formed. It can be formed on the first metal layer 32 . Further, by performing the above-described removal process and separation process, as shown in FIG. 14 , the first metal layer 32 in which the first opening 30 is formed in a predetermined pattern communicates with the first opening 30. A deposition mask 20 having a second metal layer 37 having a second opening 35 may be obtained.

(Second modified example)

As shown in FIG. 15, the resist pattern 55 provided on the substrate 51 and the first metal layer 32 has a shape in which the width of the resist pattern 55 widens as the distance from the substrate 51 increases. , may have a so-called reverse taper shape. In other words, the distance between the side surfaces 57 of the resist pattern 55 defining the gap 56 may be narrower as the distance from the substrate 51 increases. FIG. 16 is a cross-sectional view showing a case where the second metal layer 37 is deposited on the first metal layer 32 by supplying the second plating solution to the gap 56 of the resist pattern 55 . 17 is a cross-sectional view showing the deposition mask 20 obtained by performing the above-described removal process and separation process. As shown in FIG. 17, the second metal layer 37 of the deposition mask 20 according to the present modification is tapered from the first surface 20a side toward the second surface 20b side. has a shape For this reason, the angle θ1 can be efficiently increased while sufficiently securing the thickness of the second metal layer 37 and the volume of the second metal layer 37 . For example, the opening size S1 of the through hole 25 on the first surface 20a and the opening size S2 of the through hole 25 on the second surface 20b are set according to the present embodiment described above. While being the same as the case, the dimension S0 of the through hole 25 in the connection part 41 of the 1st metal layer 32 and the 2nd metal layer 37 can be made small compared with the case of this embodiment mentioned above. .

(other variations)

In addition, in the present embodiment described above, an example in which a plurality of effective regions 22 are allocated in the longitudinal direction of the deposition mask 20 has been shown. In addition, in the deposition process, an example in which a plurality of deposition masks 20 are installed on the frame 15 has been shown. However, it is not limited to this, and as shown in FIG. 18, a deposition mask 20 having a plurality of effective regions 22 arranged in a lattice shape along both the width direction and the length direction may be used.

(Regarding the concave portion of the first surface of the deposition mask)

In the above-described embodiment and each modification, the substrate 51 provided with the conductive pattern 52 having a predetermined thickness as the pattern substrate 50 for performing the first film forming step of forming the first metal layer 32 . ) is used. In addition, the first metal layer 32 is formed not only on a portion overlapping the conductive pattern 52 when viewed along the normal direction of the substrate 51 but also on a portion not overlapping the conductive pattern 52 . For this reason, if the deposition mask 20 including the first metal layer 32 and the second metal layer 37 is separated from the substrate 51 and the conductive pattern 52 of the pattern substrate 50, the first metal layer ( As shown in FIGS. 19 and 20, a concave portion 34 having a shape corresponding to the conductive pattern 52 is formed on the first surface 20a of the deposition mask 20 constituted by 32). . 19 is a cross-sectional view showing the deposition mask 20 in which the concave portions 34 are specified. 20 is an enlarged cross-sectional view of the deposition mask 20 shown in FIG. 19 .

In the following description, of the first surface 20a of the deposition mask 20, the portion where the concave portion 34 is not formed is referred to as the outermost surface 20c, and the portion where the concave portion 34 is formed is referred to as It is called the concave surface 20d. In addition, the boundary between the outermost surface 20c and the concave surface 20d of the concave portion 34 is referred to as an outer edge 34e of the concave portion 34 . The outermost surface 20c is the surface of the first metal layer 32 deposited in a portion that does not overlap with the conductive pattern 52 among the first metal layers 32 deposited in the first film forming step. In the normal direction of the deposition mask 20, the distance between the outermost surface 20c and the second surface 20b is greater than the distance between the concave surface 20d and the second surface 20b.

The depth D of the concave portion 34 is determined according to the thickness of the conductive pattern 52 of the pattern substrate 50 . For example, when the thickness of the conductive pattern 52 is in the range of 50 to 500 nm, the depth D of the concave portion 34 is in the range of 50 to 500 nm. The thickness T1 of the first metal layer 32 is in the range of 0.5 to 5.0 µm similarly to the case of the above-described embodiment.

21 is a plan view showing the case where the deposition mask 20 is viewed from the first surface 20a side along the normal direction of the deposition mask 20 . In FIG. 21 , the uppermost surface 20c and the concave surface 20d of the first surface 20a of the deposition mask 20 are provided with different hatching. 21, the end 38 of the second metal layer 37 formed on the side of the second surface 20b of the deposition mask 20, and the first metal layer 32 and the second metal layer 37 are The connecting portion 41 to be connected is indicated by a dotted line. When the wall surface 36 of the second metal layer 37 widens in parallel to the normal direction of the deposition mask 20, in a plan view, the position of the connection portion 41 is at the end 38 of the second metal layer 37. match the location

As shown in FIG. 21 , the outermost surface 20c and the outer edge 34e of the concave portion 34 extend along the end portion 33 of the first metal layer 32 and form a through hole 25 has a closed contour surrounding it. The width w of the outermost surface 20c in the direction orthogonal to the outline of the through hole 25 is equal to the width w of the portion of the first metal layer 32 that does not overlap the conductive pattern 52 shown in FIG. 7A. It is equivalent and is within the range of 0.5 to 5.0 μm, for example.

Preferably, as shown in FIG. 21 , when the deposition mask 20 is viewed along the normal direction of the deposition mask 20, the outer edge 34e of the concave portion 34 is the first metal layer 32 and the second metal layer 37 are surrounded by the contour of the connection portion 41 is connected. In other words, the second metal layer 37 is laminated on the portion of the first metal layer 32 where the concave portion 34 is formed. Advantages of such a configuration will be described later. The distance d between the outer edge 34e of the concave portion 34 and the outline of the connecting portion 41 in the surface direction of the deposition mask 20 is within a range of 1.0 to 16.5 μm, for example.

Hereinafter, an example of the advantages of forming the concave portion 34 on the first surface 20a of the deposition mask 20 will be described. FIG. 22A is a diagram showing a position adjustment step of adjusting the position of the deposition mask 20 in the surface direction of the organic EL substrate 92 . FIG. 22B is a diagram showing an adhesion step of adhering the deposition mask 20 to the organic EL substrate 92. FIG.

In the position adjustment step, in order to prevent the deposition mask 20 from coming into contact with the organic EL substrate 92 and scratching the surface of the organic EL substrate 92, the organic EL substrate 92 and the deposition mask 20 The position of the deposition mask 20 is adjusted by moving the deposition mask 20 along the plane direction of the organic EL substrate 92 with a predetermined gap between the first surfaces 20a of the ).

In this case, the smaller the distance between the organic EL substrate 92 and the first surface 20a of the deposition mask 20 is, the more precisely the position of the deposition mask 20 relative to the organic EL substrate 92 is detected. Therefore, the position of the deposition mask 20 can be precisely adjusted. On the other hand, the smaller the distance between the organic EL substrate 92 and the first surface 20a of the deposition mask 20 is, the greater the positional adjustment error of the deposition mask 20 or the warpage of the deposition mask 20. The possibility that the deposition mask 20 contacts the organic EL substrate 92 increases.

According to this embodiment, the concave portion 34 is formed on the first surface 20a of the deposition mask 20 . The concave surface 20d of the concave portion 34 is located farther from the organic EL substrate 92 than the outermost surface 20c. For this reason, the possibility that the concave surface 20d will contact the organic EL substrate 92 is lower than the possibility that the outermost surface 20c will contact the organic EL substrate 92. Therefore, by forming the concave portion 34 on the first surface 20a of the deposition mask 20, even when an error in positioning of the deposition mask 20 or warpage of the deposition mask 20 occurs, the organic EL substrate The area of the deposition mask 20 in contact with (92) can be reduced. In this way, it is possible to suppress scratches on the surface of the organic EL substrate 92 . For example, it is possible to suppress scratches on wires or electrodes previously formed on the organic EL substrate 92 .

After the position adjustment step, as shown in Fig. 22B, a close contact step of adhering the deposition mask 20 to the organic EL substrate 92 is performed. For example, by using magnetic force from a magnet (not shown), the deposition mask 20 is brought closer to the organic EL substrate 92 so that the first surface 20a of the deposition mask 20 and the organic EL substrate 92 are separated. to contact After that, a deposition process of depositing an organic material or the like on the organic EL substrate 92 is performed.

However, during the deposition process, if the gap between the end 33 of the first metal layer 32 of the deposition mask 20 and the organic EL substrate 92 is empty, the evaporation material enters the gap and the organic EL substrate 92 ), the shape of the evaporation material adhering to it fluctuates. Therefore, in order to precisely control the shape of the deposition material attached to the organic EL substrate 92, the end portion 33 of the first metal layer 32 of the deposition mask 20 is securely brought into contact with the organic EL substrate 92. Doing it becomes important. Gaps tend to occur when the thickness of the deposition mask 20 is small, and for this reason, the deposition mask 20 has a warp or a wavy shape.

Here, according to the present embodiment, since the concave portion 34 is formed on the first surface 20a of the deposition mask 20, when bringing the deposition mask 20 close to the organic EL substrate 92 during the adhesion process. , the uppermost surface 20c of the deposition mask 20 is more likely to contact the organic EL substrate 92 than the concave surface 20d. The end portion 33 of the first metal layer 32 of the deposition mask 20 (the outer edge of the deposition mask 20 on the first surface 20a) is located on the outermost surface 20c. Therefore, the end portion 33 of the first metal layer 32 of the deposition mask 20 can be brought into contact with the organic EL substrate 92 more securely.

However, a part of the first metal layer 32 that does not overlap the second metal layer 37 when viewed along the normal direction of the deposition mask 20 overlaps the second metal layer 37 of the first metal layer 32. It is easy to deform compared to the part. In addition, when the concave portion 34 is formed in the first metal layer 32 of the deposition mask 20, the thickness of the first metal layer 32 is reduced by the depth D of the concave portion 34, and as a result, The first metal layer 32 becomes more susceptible to deformation. For this reason, when force such as magnetic force from a magnet acts on the deposition mask 20, as shown in FIG. 22C, a concave portion 34 is formed in the first metal layer 32, and the second metal layer 37 It is considered that the portion that does not overlap with is deformed so that a part of the concave surface 20d of the concave portion 34 comes into contact with the organic EL substrate 92. In addition to the uppermost surface 20c of the deposition mask 20, a part of the concave surface 20d of the concave portion 34 contacts the organic EL substrate 92, thereby making the deposition mask 20 more firmly attached to the organic EL substrate. (92).

Preferably, during the adhesion process, first, the outermost surface 20c of the deposition mask 20 is in contact with the organic EL substrate 92, and then, the concave surface of the concave portion 34 of the deposition mask 20 is contacted. The deposition mask 20 is brought close to the organic EL substrate 92 so that (20d) contacts the organic EL substrate 92. As a result, the edge 33 of the outermost surface 20c of the deposition mask 20 is brought into contact with the organic EL substrate 92 reliably, and the deposition mask 20 is tightly adhered to the organic EL substrate 92. can make it

Also in the examples shown in FIGS. 19 to 22C , the deposition mask 20 includes a first metal layer 32 with first openings 30 and a second metal layer 37 with second openings 35 formed thereon. ) is provided. For this reason, similarly to the case of the present embodiment described above, the shape of the through hole 25 in which the opening size S2 in the second surface 20b is larger than the opening size S1 in the first surface 20a is easy. can be realized As a result, it is possible to suppress the deposition material 98 moving in a direction greatly inclined with respect to the normal direction N of the deposition mask 20 from adhering to the wall surface of the through hole 25 . In this way, generation of shadows can be suppressed, for example.

In addition, by forming the concave portion 34 on the first surface 20a of the deposition mask 20, the effect of reducing the area of the deposition mask 20 in contact with the organic EL substrate 92 is the deposition mask ( 20) can be realized regardless of the layer configuration. For example, although not shown, the deposition mask 20 is composed of only one metal layer (plating layer), and the concave portion 34 is formed on the surface constituting the first surface 20a of the deposition mask 20 among the metal layers. may form

(Modified Example of Arrangement of Through Holes)

In the present embodiment described above, when the deposition mask 20 is viewed along the normal direction of the deposition mask 20, an example in which a plurality of through holes 25 are arranged in a grid pattern has been shown. However, the arrangement of the through holes 25 is not particularly limited. For example, as shown in FIG. 23 , when the deposition mask 20 is viewed along the normal direction of the deposition mask 20, the plurality of through holes 25 may be arranged in a zigzag pattern.

(Example of shape of concave part)

As described above, the concave portion 34 of the first surface 20a of the deposition mask 20 is formed to correspond to the conductive pattern 52 of the pattern substrate 50 . Therefore, the shape of the concave portion 34 is determined based on the shape of the conductive pattern 52 . Hereinafter, several examples of the shape of the concave portion 34 will be described.

First, an example of a method for manufacturing the patterned substrate 50 will be described with reference to FIGS. 24A to 24D. First, the substrate 51 is prepared. Next, as shown in FIG. 24A, a conductive layer 52a made of a conductive material is formed on the substrate 51. The conductive layer 52a is a layer that becomes the conductive pattern 52 by being patterned. As the material constituting the conductive layer 52a, it is preferable to use a metal material having high adhesion to the resist pattern 54 described later. Preference is given to using, for example, copper or copper alloys.

Next, as shown in FIG. 24B, a resist pattern 54 having a predetermined pattern is formed on the conductive layer 52a. For example, first, a resist film is formed on the conductive layer 52a. For example, a so-called dry film and a film containing an acrylic photocurable resin is attached to the conductive layer 52a. Next, the resist film is exposed to light in a predetermined pattern, and then the resist film is developed to form a resist pattern 54 .

Then, as shown in FIG. 24C, the portion of the conductive layer 52a not covered by the resist pattern 54 is removed by wet etching. Then, as shown in Fig. 24D, the resist pattern 54 is removed. In this way, a patterned substrate 50 having a conductive pattern 52 having a pattern corresponding to the first metal layer 32 can be obtained.

Fig. 25 is a cross-sectional view showing an enlarged example of the conductive pattern 52 of the patterned substrate 50 obtained when the conductive layer 52a is patterned by wet etching. 26 is an enlarged cross-sectional view of the deposition mask 20 obtained when the first film forming step is performed using the pattern substrate 50 shown in FIG. 25 .

When etching that proceeds isotropically, such as wet etching, is employed, as shown in FIG. 25 , a concave portion may be formed in the side surface 52c of the conductive pattern 52 . In this case, as shown in FIG. 26 , the sidewall 34c of the concave portion 34 of the first metal layer 32 of the deposition mask 20 protrudes toward the concave portion 34 . As a result, it is considered that deformation in the normal direction of the deposition mask 20 in the portion of the first metal layer 32 where the concave portion 34 is formed is suppressed. For this reason, in the position adjustment step of adjusting the position of the deposition mask 20 in the surface direction of the organic EL substrate 92, the concave surface 20d of the first surface 20a of the deposition mask 20 is organic. Contact with the EL substrate 92 can be more reliably suppressed. Further, the end 33 of the outermost surface 20c of the deposition mask 20 can be brought into contact with the organic EL substrate 92 more reliably.

Fig. 27 is an enlarged cross-sectional view showing another example of the conductive pattern 52 of the patterned substrate 50 obtained when the conductive layer 52a is patterned by wet etching. 28 is an enlarged cross-sectional view of the deposition mask 20 obtained when the first film forming step is performed using the pattern substrate 50 shown in FIG. 27 . In the conductive pattern 52 shown in FIG. 27 , the portion of the side surface 52c in contact with the substrate 51 is outside the portion of the side surface 52c in contact with the resist pattern 54 (center of the conductive pattern 52). on the far side). In other words, the bottom portion of the conductive pattern 52 is widened outward. The conductive pattern 52 shown in FIG. 27 is obtained when the time for wet etching the conductive layer 52a is shorter than in the case of the form shown in FIG. 25 . For example, by setting the time for wet etching the conductive layer 52a to a time calculated by dividing the thickness of the conductive layer 52a by the etching rate of the conductive layer 52a, so-called just etching time, The conductive pattern 52 shown in 27 is obtained.

The position of the bottom portion of the conductive pattern 52 shown in FIG. 27 is sensitively changed according to the wet etching time. 28, when the position of the bottom portion of the conductive pattern 52 shifts outward, the position of the end portion 33 of the first metal layer 32 of the deposition mask 20 shifts outward as well. . Therefore, in order to stably position the end portion 33 of the first metal layer 32 of the deposition mask 20, it is preferable to set the wet etching time longer than the just etching time, as shown in FIG. 25 .

Meanwhile, in order to facilitate a separation process of separating the deposition mask 20 including the first metal layer 32 and the second metal layer 37 formed on the pattern substrate 50 from the pattern substrate 50, FIG. As shown in 27, it is preferable that the conductive pattern 52 has a bottom portion extending outward.

(Example of release processing)

In order to facilitate the separation process of separating the deposition mask 20 from the pattern substrate 50, the pattern substrate 50 may be subjected to a release treatment before performing the first film forming process. An example of the mold release process will be described below.

First, a degreasing treatment for removing oil from the surface of the patterned substrate 50 is performed. For example, an acidic degreasing liquid is used to remove oil from the surface of the conductive pattern 52 of the pattern substrate 50 .

Then, an activation process for activating the surface of the conductive pattern 52 is performed. For example, the surface of the conductive pattern 52 is brought into contact with the same acidic solution as the acidic solution contained in the plating solution used in the subsequent plating process. For example, when the plating solution contains nickel sulfamate, sulfamic acid is brought into contact with the surface of the conductive pattern 52 .

Next, an organic film formation process for forming an organic film on the surface of the conductive pattern 52 is performed. For example, a release agent containing an organic material is brought into contact with the surface of the conductive pattern 52 . At this time, the thickness of the organic film is set so small that the electrical resistance of the organic film is not inhibited by the organic film from depositing the first metal layer 32 by electrolytic plating.

In addition, after the degreasing treatment, the activation treatment, and the organic film formation treatment, a water washing treatment for washing the pattern substrate 50 with water is performed, respectively.

According to this modified example, the separation process of separating the deposition mask 20 from the pattern substrate 50 can be facilitated by performing the release treatment on the pattern substrate 50 before performing the first film forming process.

In addition, although several modified examples of the above-described embodiment have been described, it is also possible to apply a plurality of modified examples in appropriate combination as a matter of course.

20: deposition mask
20a: first side
20b: second side
20c: top surface
20d: concave
22: effective area
23: surrounding area
25: through hole
30: first opening
31: wall
32: first metal layer (first plating layer)
33: end
34: recess
34c: side wall
34e: outer edge
35: second opening
36: wall
37: second metal layer (second plating layer)
38: end
41: connection part
50: pattern substrate
51 Substrate
52: conductive pattern
52a: conductive layer
52c: side
53: end
54: resist pattern
55: resist pattern
56: Gap
57: side
92 organic EL substrate
98: deposition material

Claims (14)

A deposition mask manufacturing method for manufacturing a deposition mask having a plurality of through holes,
A first film forming step of forming a first metal layer having first openings in a predetermined pattern on an insulating substrate;
a second film forming step of forming a second metal layer having a second opening communicating with the first opening on the first metal layer;
A separation step of separating the combination of the first metal layer and the second metal layer from the substrate;
The second film forming step includes a resist formation step of forming a resist pattern on the substrate and on the first metal layer with a predetermined gap therebetween, and forming a resist pattern on the first metal layer in the gap between the resist patterns. Including a plating treatment step of depositing a metal layer,
The resist forming step is performed such that the first opening of the first metal layer is covered by the resist pattern and the gap of the resist pattern is positioned on the first metal layer;
On the substrate, a conductive pattern having a pattern corresponding to the first metal layer is formed,
The method of manufacturing a deposition mask, wherein the first film forming step includes a plating treatment step of depositing the first metal layer on the conductive pattern. The method of claim 1 , wherein the plating treatment step of the first film forming step includes an electrolytic plating treatment step of depositing the first metal layer on the conductive pattern by flowing a current through the conductive pattern. . 3. The method of claim 2, wherein in the first film forming step, the first metal layer is formed anywhere on a portion overlapping the conductive pattern and a portion not overlapping the conductive pattern when viewed along a normal direction of the substrate, ,
In the separation step, a concave portion having a shape corresponding to the conductive pattern is formed in the first metal layer separated from the substrate and the conductive pattern. The electrolytic plating according to any one of claims 1 to 3, wherein the plating treatment step of the second film forming step deposits the second metal layer on the first metal layer by applying an electric current through the first metal layer. A method for manufacturing a deposition mask, comprising a processing step. The method of claim 1 , wherein a portion of the first metal layer connected to the second metal layer has a thickness of 5 μm or less. The method of claim 1 , wherein a thickness of the second metal layer is in a range of 3 μm to 25 μm. A deposition mask having a plurality of through holes extending from a first surface to a second surface,
A metal layer in which the through holes are formed in a predetermined pattern;
When a portion of the through holes located on the first surface is referred to as a first opening and a portion of the through holes located on the second surface is referred to as a second opening, the through hole is When the deposition mask is viewed along a normal direction, an outline of the second opening is configured to surround an outline of the first opening;
A concave portion is formed on the first surface,
The metal layer has a first metal layer formed with the first opening and the concave portion, and a second metal layer laminated on the first metal layer and formed with the second opening,
The deposition mask of claim 1 , wherein an outline of the concave portion formed in the first metal layer surrounds the first opening when the deposition mask is viewed along a normal direction of the deposition mask. The deposition mask of claim 7 , wherein a width of a portion of the first surface in which the concave portion is not formed is in a range of 0.5 to 5.0 μm. The deposition mask of claim 8 , wherein a thickness of a portion of the first metal layer connected to the second metal layer is 5 μm or less. The deposition mask according to any one of claims 7 to 9, wherein a thickness of the second metal layer is in a range of 3 to 25 μm. The deposition mask according to any one of claims 7 to 9, wherein the metal layer is a plating layer. delete delete delete

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