Method for manufacturing a deposition mask

Abstract

To provide a method of producing a vapor deposition mask having excellent vapor deposition efficiency by a simple scheme.SOLUTION: A method of producing a vapor deposition mask includes forming a first plating layer using a resist pattern as a mask, deforming the resist pattern, and forming a second plating layer on the first plating layer using the deformed resist pattern as a mask. By deforming the resist pattern, the deformed resist pattern may be overlaid on a portion of the first plating layer.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a method for manufacturing a deposition mask. [Background technology]

[0002] Typically, in the process of manufacturing organic EL display devices, vacuum deposition is used to form a layer composed of organic EL material (organic EL layer). In vacuum deposition, a deposition mask is placed close to the substrate to be processed, and the organic EL material is deposited onto the substrate through the deposition mask. The deposition mask has multiple openings. The organic EL material passes through the multiple openings to reach the substrate, making it possible to selectively form the organic EL layer at positions corresponding to the multiple openings.

[0003] The deposition material flying from the deposition source hits the deposition mask from various angles. Therefore, if the deposition material advances obliquely toward the deposition mask, it may not be able to pass through the openings, resulting in reduced deposition efficiency. Therefore, deposition masks have been developed that prevent the above-mentioned phenomenon by forming openings in the deposition mask with a shape that widens toward the deposition source (e.g., a tapered shape) (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-087840 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-074938 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of one embodiment of the present invention is to provide a method for manufacturing a deposition mask with excellent deposition efficiency by a simple method. [Means for solving the problem]

[0006] A method for manufacturing a deposition mask in one embodiment of the present invention includes forming a first plating layer using a resist pattern as a mask, deforming the resist pattern, and forming a second plating layer on the first plating layer using the deformed resist pattern as a mask.

[0007] A method for manufacturing a deposition mask in one embodiment of the present invention includes forming a second resist layer on a first resist layer, etching the second resist layer to form a second resist pattern, etching the first resist layer using the second resist pattern as a mask to form a first resist pattern, and forming a plating layer using the first resist pattern and the second resist pattern as masks, wherein the first resist pattern is etched so that the width of the first resist pattern is narrower than the width of the second resist pattern in a cross-sectional view. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view showing a configuration of a deposition mask according to a first embodiment of the present invention. [Figure 2] 1 is a cross-sectional view showing a configuration of a deposition mask according to a first embodiment of the present invention. [Figure 3] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 4] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 5] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 6] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 7] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 8] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 9]2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 10] 1A to 1C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a first embodiment of the present invention. [Figure 11] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 12] 2A to 2C are cross-sectional views illustrating a method for manufacturing the deposition mask according to the first embodiment of the present invention. [Figure 13] 5A to 5C are cross-sectional views illustrating a method for manufacturing a vapor deposition mask according to Modification 1 of the first embodiment of the present invention. [Figure 14] 5A to 5C are cross-sectional views illustrating a method for manufacturing a vapor deposition mask according to Modification 1 of the first embodiment of the present invention. [Figure 15] 10A to 10C are cross-sectional views showing a method for manufacturing a vapor deposition mask according to Modification 2 of the first embodiment of the present invention. [Figure 16] 10A to 10C are cross-sectional views showing a method for manufacturing a vapor deposition mask according to Modification 2 of the first embodiment of the present invention. [Figure 17] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 18] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 19] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 20] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 21] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 22] 5A to 5C are cross-sectional views illustrating a method for manufacturing a deposition mask according to a second embodiment of the present invention. [Figure 23] 10A to 10C are cross-sectional views showing a method for manufacturing a vapor deposition mask according to Modification 1 of the second embodiment of the present invention. [Figure 24] 10A to 10C are cross-sectional views showing a method for manufacturing a vapor deposition mask according to Modification 1 of the second embodiment of the present invention. [Figure 25] 10A to 10C are cross-sectional views illustrating a method for manufacturing a vapor deposition mask according to a first modified example of the [Figure 26] 10A to 10C are cross-sectional views illustrating a method for manufacturing a vapor deposition mask according to a first modified example of the DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention can be embodied in various forms without departing from the spirit of the present invention, and should not be construed as being limited to the description of the embodiments exemplified below. To clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part more schematically than the actual form, but these are merely examples and do not limit the interpretation of the present invention. In this specification and each drawing, elements having the same functions as those described with reference to the previous drawings may be assigned the same reference numerals, and redundant explanations may be omitted.

[0010] In this specification and claims, when expressing an aspect of placing another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both a case in which another structure is placed directly on top of a certain structure so as to be in contact with the certain structure, and a case in which another structure is placed above a certain structure via yet another structure.

[0011] In this specification, unless otherwise specified, expressions such as "α includes A, B, or C," "α includes any one of A, B, and C," and "α includes one selected from the group consisting of A, B, and C" do not exclude cases where α includes multiple combinations of A to C. Furthermore, these expressions do not exclude cases where α includes other elements.

[0012] First Embodiment [Configuration of deposition mask] Fig. 1 is a plan view showing the configuration of a deposition mask 100 according to the first embodiment of the present invention. Fig. 2 is a cross-sectional view showing the configuration of the deposition mask 100 according to the first embodiment of the present invention. Specifically, the cross-sectional view shown in Fig. 2 shows a cross section taken along line A-A' in Fig. 1. As shown in Figs. 1 and 2, the deposition mask 100 has a thin-film mask portion 110 formed by electroforming, a holding frame 120 that holds the mask portion 110, and a connection portion 130 that connects the mask portion 110 and the holding frame 120.

[0013] The mask section 110 has a plurality of panel regions 115. When evaporating the organic EL material, a substrate to be evaporated (not shown) is arranged so that the display region of the organic EL display device overlaps with each panel region 115. A plurality of openings 111 are provided in each panel region 115 in accordance with the pixel pitch of the organic EL display device. Areas of the mask section 110 other than the openings 111 are called non-openings 112. The non-openings 112 are areas surrounding each opening 111. The non-openings 112 correspond to portions of each panel region 115 that block the evaporation material.

[0014] During deposition, the deposition mask 100 and the substrate to be deposited are aligned so that the deposition regions (regions where a thin film is to be formed) of the substrate to be deposited overlap the openings 111, and the non-deposition regions of the substrate to be deposited overlap the non-openings 112. Vapor of the deposition material passes through the openings 111 and reaches the substrate to be deposited, whereby the deposition material is deposited in the deposition regions to form a thin film.

[0015] The holding frame 120 is provided on the outer periphery of the mask unit 110 so as to surround the multiple panel regions 115 of the mask unit 110 in a plan view. In other words, the holding frame 120 functions as a member that holds the thin-film-like mask unit 110. Note that in FIG. 1, the holding frame 120 is provided only on the outer periphery of the mask unit 110. However, this is not limiting, and the holding frame 120 may be provided in a lattice pattern.

[0016] The connection portion 130 is a member that connects the mask portion 110 and the holding frame 120. In the deposition mask 100 of this embodiment, the mask portion 110 and the holding frame 120 are connected via the connection portion 130. That is, as shown in FIG. 2 , the mask portion 110 and the holding frame 120 are not directly connected.

[0017] In the above configuration, the mask portion 110 is made of a thin-film plating layer. The mask portion 110 of this embodiment is a thin film formed by electroplating. The thickness d1 of the mask portion 110 is, for example, 3 μm or more and 20 μm or less (preferably, 5 μm or more and 10 μm or less). In this embodiment, the thickness of the mask portion 110 is 5 μm. The holding frame 120 is made of an alloy such as invar. Invar alloys have a small thermal expansion coefficient at room temperature, which has the advantage of not applying stress to the mask portion 110. The thickness d2 of the holding frame 120 is, for example, 0.5 mm or more and 3.0 mm or less (preferably, 0.8 mm or more and 2.0 mm or less). In this embodiment, the thickness of the holding frame 120 is 1 mm.

[0018] In this embodiment, invar is used as the metal material for the mask unit 110, the holding frame 120, and the connecting unit 130. Invar has a smaller thermal expansion coefficient at room temperature and at temperatures during the organic EL device formation process than nickel and the like, and its thermal expansion coefficient is close to that of glass. Therefore, by using invar as the material for the deposition mask 100, the influence of thermal expansion between the mask unit 110 and a glass substrate can be suppressed in the manufacturing process of the deposition mask 100, which will be described later. Furthermore, during deposition, there is an advantage in that misalignment due to thermal expansion between the deposition mask and the deposition target substrate (usually a glass substrate) is reduced, thereby improving the positional accuracy of deposition. However, this is not limiting, and other materials other than invar may be used as long as they have a thermal expansion coefficient close to that of glass. Furthermore, the holding frame 120 may be made of a metal material different from that of the mask unit 110 and the connecting unit 130.

[0019] [Method of manufacturing the deposition mask 100] A method for manufacturing the deposition mask 100 of this embodiment will be described in detail with reference to the drawings. Figures 3 to 12 are diagrams showing the method for manufacturing the deposition mask 100 of the first embodiment of the present invention.

[0020] 3, a seed layer 210 and a resist pattern 220 are formed on a substrate 200. In this embodiment, a glass substrate is used as the substrate 200. However, the present invention is not limited to this example, and the substrate 200 may also be a metal substrate or a ceramic substrate.

[0021] The seed layer 210 is a metal layer provided for growing a plating layer. In this embodiment, a nickel alloy (specifically, Invar) is used as the material for the plating layer 230a described later, and therefore a metal layer containing copper (Cu) is used as the seed layer 210. However, the present invention is not limited to this example, and other metal layers may be used as long as they can function as a seed layer.

[0022] The seed layer 210 may be formed by sputtering or CVD (Chemical Vapor Deposition). The thickness of the seed layer 210 may be sufficient to ensure the conductivity required for growing the plating layer 230 described below. For example, the thickness of the seed layer 210 may be in the range of 50 nm to 500 nm.

[0023] The resist pattern 220 is formed by applying a photosensitive resin material onto the seed layer 210, followed by exposure and development (etching) processes. The region where the resist pattern 220 is formed corresponds to the region where the multiple openings 111 of the mask portion 110 shown in FIGS. 1 and 2 are provided.

[0024] Next, as shown in Fig. 4, a plating layer 230a is formed in an area where the resist pattern 220 is not arranged. That is, the area where the plating layer 230a is formed corresponds to an area where the non-opening portion 112 of the mask portion 110 shown in Figs. 1 and 2 is provided. In this embodiment, before forming the plating layer 230a, the surface of the seed layer 210 is pretreated with a release agent. As the release agent, for example, Nikkanontack (registered trademark) manufactured by Nippon Chemical Industry Co., Ltd. may be used.

[0025] In this embodiment, the plating layer 230a is a metal layer made of a nickel alloy (specifically, invar). In this embodiment, electroplating is performed by passing a current through the seed layer 210 in an aqueous solution containing metal ions of the nickel alloy. When a current is passed through the seed layer 210, the plating layer 230a is formed on the surface of the seed layer 210. The thickness of the plating layer 230a can be adjusted by controlling the electroplating time. In this embodiment, the thickness of the plating layer 230a is adjusted to a range of 0.5 μm to 5 μm. Specifically, in this embodiment, the thickness of the plating layer 230a is set to 2 μm. In this embodiment, an example in which the plating layer 230a is formed of invar has been described, but the present invention is not limited to this example, and other metal materials that can be used for electroplating may be used.

[0026] After forming the plating layer 230a, the resist pattern 220 is deformed to form a resist pattern 225. Specifically, as shown in FIG. 5, the cross-sectional shape of the resist pattern 220 is changed so that a portion of the resist pattern 220 overlaps a portion of the plating layer 230a. Therefore, the distance between the resist patterns 225 shown in FIG. 5 is shorter than the distance between the resist patterns 220 shown in FIG. 4. In addition, this embodiment shows an example in which the upper portion of the resist pattern 225 (the portion located above the plating layer 230a) is deformed to have a forward tapered shape. However, the shape of the upper portion of the resist pattern 225 is not limited to this example and varies depending on the processing conditions when deforming the resist pattern 220 and the material constituting the resist pattern 220.

[0027] The resist pattern 220 can be deformed, for example, by expanding the resist pattern 220 by heat treatment (for example, heat treatment at about 200° C.), or by contacting the resist pattern 220 with a specific solution (for example, an organic alkaline solution such as a developer) or gas (for example, a reactive gas such as an organic silane) to cause the resist pattern 220 to swell. When forming the resist pattern 225, an appropriate resist material should be used depending on whether the resist pattern 220 is expanded by heat or swelled by contact with a solution or the like.

[0028] While the above mainly describes an example of increasing the volume of the resist pattern 220, the deformation of the resist pattern 220 required in the present invention means that a portion of the resist pattern 220 that protrudes above the plating layer 230a is formed to cover the plating layer 230a. For example, this may be achieved by deforming only the cross-sectional shape of the resist pattern 220 without increasing the cross-sectional area itself, or by deforming only the outer shape of the resist pattern 220 without changing the volume of the resist pattern 220. Therefore, deformation of the cross-sectional shape of the resist pattern 220 is not necessarily limited to methods that rely on expansion or swelling.

[0029] Next, as shown in FIG. 6 , electroplating is performed using the deformed resist pattern 225 as a mask to form a plating layer 230b in areas where the resist pattern 225 is not disposed. The plating layer 230b is formed between the resist patterns 225. In this embodiment, the plating layers 230a and 230b are formed from the same nickel alloy (specifically, Invar), but this is not a limitation and they may be formed from different metal layers. In this embodiment, the thickness of the plating layer 230b is adjusted to a range of 2 μm to 15 μm. Specifically, in this embodiment, the thickness of the plating layer 230b is set to 3 μm. In this embodiment, an example is shown in which the plating layer 230b is formed from Invar, but this is not a limitation and other metal materials that can be used for electroplating may be used.

[0030] 6, the spacing between first plating layers 230a formed at positions sandwiching deformed resist pattern 225 (i.e., the spacing between adjacent first plating layers 230a) is smaller than the spacing between second plating layers 230b (i.e., the spacing between adjacent second plating layers 230b) formed at positions sandwiching deformed resist pattern 225. In other words, the width of the portion of deformed resist pattern 225 sandwiched by first plating layers 230a is smaller than the width of the portion of deformed resist pattern 225 sandwiched by second plating layers 230b.

[0031] After the plating layer 230b is formed, the resist pattern 225 is removed as shown in FIG. 7. By removing the resist pattern 225, a pattern composed of the plating layers 230a and 230b is formed. The pattern composed of the plating layers 230a and 230b corresponds to the non-opening portion 112 (i.e., the shielding portion that shields the deposition material) shown in FIGS. 1 and 2. The region formed by removing the resist pattern 225 corresponds to the opening portion 111 shown in FIGS. 1 and 2. That is, in this embodiment, the total film thickness of the plating layers 230a and 230b determines the film thickness of the mask portion 110.

[0032] As shown in FIG. 7, in a cross-sectional view, the width of the upper surface of the plating layer 230b is narrower than the width of the upper surface of the plating layer 230a. Here, the difference between the width of the upper surface of the plating layer 230a and the width of the upper surface of the plating layer 230b is defined as X. As a result, the diameter of the upper end of the opening 111 becomes wider than the diameter of the lower end of the opening 111, which reduces the phenomenon in which the deposition material advancing obliquely toward the deposition mask cannot pass through the opening. The length of the difference X can be controlled by the amount of deformation of the resist pattern 220 shown in FIG. 5.

[0033] Next, as shown in Fig. 8, the holding frame 120 is placed on a part of the non-opening portion 112 (a part not used as the mask portion 110). The holding frame 120 is adhered onto the non-opening portion 112 by utilizing the adhesive force of an adhesive layer (not shown). The holding frame 120 is placed so as to surround the mask portion 110, as shown in Fig. 1.

[0034] 9, a resist pattern 240 is formed on the mask portion 110 and the holding frame 120. The resist pattern 240 is formed by applying a photosensitive resin material onto the mask portion 110 and the holding frame 120, and then performing an exposure process and a development (etching) process. The region where the resist pattern 240 is formed is a region other than the region where the connection portion 130 shown in FIGS. 1 and 2 is provided.

[0035] Next, as shown in Fig. 10, the connection portion 130 is formed in the region where the resist pattern 240 is not arranged. The connection portion 130 is formed using electroplating. Specifically, the connection portion 130 is selectively formed in the region where the resist pattern 240 is not arranged, using the holding frame 120, the non-opening portion 112, and the seed layer 210 as a seed layer. Therefore, as shown in Fig. 10, the connection portion 130 is formed from the side wall of the holding frame 120 to the mask portion 110.

[0036] In this embodiment, the connection portion 130 is formed continuously from the side wall of the holding frame 120 to the top of the mask portion 110. This allows the holding frame 120 and the mask portion 110 to be connected via the connection portion 130. An opening provided in the part of the mask portion 110 that overlaps with the connection portion 130 serves to physically separate the mask portion 110 and the holding frame 120 and to improve the adhesion between the mask portion 110 and the connection portion 130.

[0037] In this embodiment, the connection portion 130 is formed of a plating layer (metal layer) made of a nickel alloy (specifically, invar). In this embodiment, the thickness of the connection portion 130 is adjusted to a range of 50 nm to 200 nm. In this embodiment, an example in which the connection portion 130 is made of invar is shown, but the present invention is not limited to this example, and other metal materials that can be used for electroplating may also be used.

[0038] 11, after forming the connection portion 130, the resist pattern 240 is removed and then the substrate 200 is removed. Specifically, the holding frame 120 is fixed by suction or the like, and then the substrate 200 is removed by mechanically peeling the substrate 200 from the mask portion 110, the holding frame 120, and the connection portion 130. At this time, the seed layer 210 and a part of the mask portion 110 (non-opening portion 112 overlapping the holding frame 120) are removed together with the substrate 200.

[0039] Through the above manufacturing process, a deposition mask 100 having the cross-sectional structure shown in FIG. 12 is completed. As shown in FIG. 12, the deposition mask 100 of this embodiment has a structure in which a thin-film mask portion 110 is connected to a holding frame 120 via a connecting portion 130. In this case, the width of the openings 111 in a cross-sectional view is wider at the upper end (the distance between the plating layers 230b) than at the lower end (the distance between the plating layers 230a). This reduces the phenomenon in which the deposition material advancing obliquely toward the deposition mask 100 is unable to pass through the openings 111. Furthermore, in this embodiment, the diameter of the openings 111 on the deposition source side of the deposition mask 100 can be increased simply by modifying the resist pattern used during electroplating, without performing patterning. As such, according to this embodiment, a deposition mask 100 with excellent deposition efficiency can be realized by a simple method.

[0040] (Variation 1) In this modification, an example will be described in which the resist pattern 220 is modified into a shape different from that shown in Fig. 5. Figs. 13 and 14 are cross-sectional views showing a method for manufacturing a vapor deposition mask 100 in modification 1 of the first embodiment of the present invention.

[0041] 4 is obtained using the same procedure as in the first embodiment, and then a resist pattern 225a is formed by deforming the resist pattern 220 as shown in FIG. 13. In this modification, the upper part of the resist pattern 225a (the part above the plating layer 230a) is approximately circular. The difference from FIG. 5 is that the resist pattern 225a is not in contact with the upper surface of the plating layer 230a, but when this shape is viewed in a plan view, the resist pattern 225a overlaps the plating layer 230a.

[0042] After forming the resist pattern 225a, a plating layer 230b is formed again by electroplating. After the plating layer 230b is formed, the resist pattern 225a is removed. As a result, openings 111a and non-openings 112a are formed as shown in FIG.

[0043] 14 shows an enlarged view of the end portion (region surrounded by a frame line 10) of the non-opening portion 112a. As shown in this enlarged view, the side surface of the plating layer 230b is curved to form a recess. Furthermore, as is clear from the inclination of a line 11 connecting the edge of the upper surface and the edge of the lower surface of the plating layer 230b, the width (diameter) increases upward (toward the deposition source during deposition). Therefore, in this modified example, it is possible to reduce the phenomenon in which the deposition material proceeding obliquely toward the deposition mask 100 cannot pass through the opening portion 111a.

[0044] Furthermore, as shown by the frame line 12 in the enlarged view, in this modification, the edge of the lower surface of the plating layer 230b and the edge of the upper surface of the plating layer 230a are substantially aligned. That is, in this modification, when the resist pattern 220 is deformed, the resist pattern 220 expands laterally without coming into contact with the surface of the plating layer 230a.

[0045] (Variation 2) In this modification, an example will be described in which the resist pattern 220 is modified into a shape different from that shown in Figures 5 and 13. Figures 15 and 16 are cross-sectional views showing a method for manufacturing a deposition mask 100 in modification 2 of the first embodiment of the present invention.

[0046] 4 is obtained using the same procedure as in the first embodiment, and then a resist pattern 225b is formed by deforming the resist pattern 220 as shown in FIG. 15. In this modification, an example is shown in which the upper part of the resist pattern 225b (the part above the plating layer 230a) is substantially elliptical. While the cross-sectional shape is qualitatively the same as in FIG. 13 described above, the example shown in FIG. 15 differs in that a part of the resist pattern 225a is in contact with the upper surface of the plating layer 230a.

[0047] After forming the resist pattern 225b, a plating layer 230b is formed again by electroplating. After the plating layer 230b is formed, the resist pattern 225a is removed. As a result, openings 111b and non-openings 112b are formed as shown in FIG.

[0048] 16 shows an enlarged view of the end portion (region surrounded by a frame line 15) of the non-opening portion 112b. As shown in this enlarged view, the side surface of the plating layer 230b is curved to form a recess. Furthermore, as is clear from the inclination of a line 16 connecting the edge of the upper surface and the edge of the lower surface of the plating layer 230b, the width (diameter) increases upward (toward the deposition source during deposition). Therefore, in this modified example, it is possible to reduce the phenomenon in which the deposition material proceeding obliquely toward the deposition mask 100 cannot pass through the opening portion 111b.

[0049] Furthermore, as shown by the frame line 17 in the enlarged view, in this modification, unlike the above-described modification 1, there is a distance between the edge of the lower surface of the plating layer 230b and the edge of the upper surface of the plating layer 230a. That is, in the example shown in Fig. 16, a part of the upper surface of the plating layer 230a is exposed. In this modification, when the resist pattern 220 is deformed and expands laterally, the upwardly protruding portion of the plating layer 230a in the resist pattern 220 comes into contact with the surface of the plating layer 230a, thereby forming the above-described exposed surface.

[0050] Second Embodiment In this embodiment, an example of manufacturing the deposition mask 100 by a method different from that of Embodiment 1 will be described. Note that in the method of manufacturing the deposition mask 100 of this embodiment, the same elements as those in the first embodiment will be denoted by the same reference numerals and detailed description thereof will be omitted.

[0051] A method for manufacturing the deposition mask 100 of this embodiment will be described in detail with reference to the drawings. Figures 17 to 26 are diagrams showing the method for manufacturing the deposition mask 100 of the first embodiment of the present invention.

[0052] First, as shown in Fig. 17, a seed layer 210, a resist layer 261, and a resist layer 262 are formed on a substrate 200. In this embodiment, a non-photosensitive resin material is used for the resist layer 261, and a photosensitive resin material is used for the resist layer 262. However, this is not limiting, and a photosensitive resin material may also be used for the resist layer 216. In this embodiment, a material having a higher etching rate with respect to a developer than the resist layer 262 is used for the resist layer 261.

[0053] 17, the film thickness of the resist layer 261 is smaller than the film thickness of the resist layer 262. The film thickness of the resist layer 262 is preferably at least twice (more preferably, at least three times and at most five times) the film thickness of the resist layer 261. As will be described later, the shape of the opening 111 constituting the mask portion 110 can be set by the ratio of the film thicknesses of the resist layer 261 and the resist layer 262.

[0054] After the resist layer 261 and the resist layer 262 are formed, a resist pattern 262a is formed by performing an exposure process and a development (etching) process on the resist layer 262, as shown in Fig. 18. The region where the resist pattern 262a is formed corresponds to the region where the multiple openings 111 of the mask portion 110 described with reference to Figs.

[0055] After the resist pattern 262a is formed, a resist pattern 261a is formed by performing a development (etching) process on the resist layer 261 using the resist pattern 262a as a mask, as shown in Fig. 19. The region where the resist pattern 261a is formed corresponds to the region where the multiple openings 111 of the mask portion 110 described with reference to Figs.

[0056] 19, the resist pattern 261a is etched so that the width of the resist pattern 261a is narrower than the width of the resist pattern 262a in a cross-sectional view. In this embodiment, as described above, a material having a higher etching rate with respect to a developer than the resist layer 262 is used for the resist layer 261. Therefore, by over-etching, the side surfaces of the resist pattern 261a are recessed, and a state in which the resist pattern 262a overhangs the resist pattern 261a can be formed. At this time, the amount of recession of the resist pattern 261a can be controlled by the etching time.

[0057] 20, a plating layer 230 is formed in an area where the resist pattern 261a and the resist pattern 262a are not arranged. That is, the area where the plating layer 230 is formed corresponds to an area where the non-opening portion 112 of the mask portion 110 described in the first embodiment with reference to FIGS. 1 and 2 is provided. In this embodiment, the plating layer 230 is a metal layer made of Invar.

[0058] In this embodiment, the plating layer 230 is grown until at least its upper surface is positioned between the resist patterns 262a. That is, the film thickness of the plating layer 230 is set to be at least greater than the film thickness of the resist patterns 261a. In this embodiment, the thickness of the plating layer 230 is adjusted to be in the range of 3 μm to 20 μm. Specifically, in this embodiment, the thickness of the plating layer 230 is set to be 5 μm.

[0059] After the plating layer 230 is formed, the resist patterns 261a and 262a are removed as shown in FIG. 21. By removing the resist patterns 261a and 262a, a pattern constituted by the plating layer 230 is formed. The pattern constituted by the plating layer 230 corresponds to the non-opening portion 112 (i.e., the shielding portion that shields the deposition material) shown in FIGS. 1 and 2. The region formed by removing the resist patterns 261a and 262a corresponds to the opening portion 111 described with reference to FIGS. 1 and 2. That is, in this embodiment, the film thickness of the plating layer 230 determines the film thickness of the mask portion 110.

[0060] As shown in FIG. 21 , in a cross-sectional view, the width of the upper surface of the non-opening 112 is narrower than the width of the lower surface of the non-opening 112. Here, the difference between the width of the upper surface of the non-opening 112 and the width of the lower surface of the non-opening 112 is defined as X. As a result, the diameter of the upper end of the opening 111 becomes wider than the diameter of the lower end of the opening 111, and it is possible to reduce the phenomenon in which the deposition material proceeding obliquely toward the deposition mask cannot pass through the opening. The length of the difference X described above can be controlled by the retraction amount of the resist pattern 261a shown in FIG. 19 .

[0061] As described above, once the openings 111 and non-openings 112 that constitute the mask portion 110 are formed, a deposition mask 100 shown in FIG. 22 is completed through processes similar to those of FIGS. 8 to 11 of the first embodiment. As shown in FIG. 22, the deposition mask 100 of this embodiment has a structure in which the thin-film mask portion 110 is connected to a holding frame 120 via connecting portions 130. In this case, the width of the upper ends of the openings 111 in a cross-sectional view (the distance between the upper surfaces of the non-openings 112) is wider than the width of the lower ends (the distance between the lower surfaces of the non-openings 112). This reduces the phenomenon in which the deposition material that advances obliquely toward the deposition mask 100 cannot pass through the openings 111. As such, according to this embodiment, a deposition mask 100 with excellent deposition efficiency can be realized.

[0062] (Variation 1) In this modification, an example will be described in which the resist pattern 262a has a shape different from that shown in Fig. 18. Figs. 23 to 26 are cross-sectional views showing a method for manufacturing the deposition mask 100 in modification 1 of the second embodiment of the present invention.

[0063] 17 is obtained in the same manner as in the second embodiment, an exposure process and a development (etching) process are performed on the resist layer 262 to form a resist pattern 262a having an inverse tapered shape, as shown in Fig. 23. That is, in this modification, the width of the resist pattern 262a in a cross-sectional view increases upward (in the direction away from the resist layer 261).

[0064] In this embodiment, a photosensitive resin material is used for the resist layer 262 that constitutes the resist pattern 262a. Photosensitive resin materials have the advantage that they can easily form a reverse tapered shape by adjusting exposure conditions, etc. However, this is not limited to this example, and the resist pattern 262a may also have a forward tapered shape. When the resist layer 262 is formed from a photosensitive resin material, the tapered shape can be controlled by adjusting exposure conditions, etc., so it is possible to control either a reverse tapered shape or a forward tapered shape. Note that the region where the resist pattern 262a is formed corresponds to the region where the multiple openings 111 of the mask portion 110 described with reference to FIGS. 1 and 2 are provided.

[0065] After the resist pattern 262a is formed, a development (etching) process is performed on the resist layer 261 using the resist pattern 262a as a mask, thereby forming a resist pattern 261a, as shown in Fig. 24. In this modification, the resist pattern 261a is also etched so that the width of the resist pattern 261a is narrower than the width of the resist pattern 262a in a cross-sectional view.

[0066] Next, as shown in Fig. 25, a plating layer 230 is formed in areas where the resist patterns 261a and 262a are not arranged. After the plating layer 230 is formed, the resist patterns 261a and 262a are removed, as shown in Fig. 26. By removing the resist patterns 261a and 262a, a pattern made up of the plating layer 230 is formed.

[0067] The pattern formed by the plating layer 230 corresponds to the non-opening portion 112 (i.e., the shielding portion that shields the deposition material) shown in Figures 1 and 2. The region formed by removing the resist pattern 261a and the resist pattern 262a corresponds to the opening portion 111 described with reference to Figures 1 and 2.

[0068] 26, the non-opening portion 112 has a forward tapered shape in cross section. That is, as shown in the enlarged view corresponding to the portion surrounded by the frame line 20, an inclined surface 21 is formed in the upper portion of the non-opening portion 112 such that the film thickness of the non-opening portion 112 increases with increasing distance from the opening portion 111. Therefore, the diameter of the upper end of the opening portion 111 in this modification can be made larger than the diameter of the upper end of the opening portion 111 shown in FIG. 21. This can further reduce the phenomenon in which the deposition material proceeding obliquely toward the deposition mask cannot pass through the opening portion.

[0069] The above-described embodiments of the present invention can be appropriately combined as long as they are not mutually inconsistent. A method for manufacturing a deposition mask according to any of the embodiments, in which a person skilled in the art appropriately adds or deletes components or modifies the design, or adds or omits steps or modifies conditions, is also included in the scope of the present invention as long as it includes the gist of the present invention.

[0070] Furthermore, even if there are other effects and advantages different from those brought about by the aspects of each of the above-mentioned embodiments, if they are clear from the description in this specification or can be easily predicted by a person skilled in the art, they are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0071] 21...inclined surface, 100...evaporation mask, 110...mask portion, 111, 111a, 111b...opening portion, 112, 112a, 112b...non-opening portion, 115...panel region, 120...holding frame, 130...connecting portion, 200...substrate, 210...seed layer, 216...resist layer, 220, 225, 225a, 225b...resist pattern, 230, 230a, 2330b...plating layer, 240...resist pattern, 261, 262...resist layer, 261a, 262a...resist pattern

Claims

1. forming a first plating layer using the resist pattern as a mask; Deforming the resist pattern; forming a second plating layer on the first plating layer using the deformed resist pattern as a mask.

2. The method for manufacturing a deposition mask according to claim 1 , further comprising deforming the resist pattern so that the deformed resist pattern overlaps a portion of the first plating layer.

3. The method for manufacturing a deposition mask according to claim 1 , wherein the deforming of the resist pattern includes immersing the resist pattern in an organic alkaline solvent.

4. The method for manufacturing a deposition mask according to claim 1 , wherein the deforming the resist pattern includes heating the resist pattern.

5. 2. The method for manufacturing a deposition mask according to claim 1, wherein an interval between the first plating layers formed at positions sandwiching the deformed resist pattern is smaller than an interval between the second plating layers formed at positions sandwiching the deformed resist pattern.

6. forming the resist pattern on a metal layer; The method for manufacturing a deposition mask according to claim 1 , wherein the first plating layer and the second plating layer are formed by electroplating.

7. The method for manufacturing a deposition mask according to claim 1 , further comprising removing the deformed resist pattern after forming the second plating layer.

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