Intermediate deposition mask products

Abstract

To provide an intermediate product of a vapor deposition mask capable of accurately detecting a contour of a vapor deposition mask.SOLUTION: An intermediate product of a vapor deposition mask includes a plurality of vapor deposition mask parts 51 and a support part 56 that surrounds the vapor deposition mask parts and is partially connected to the vapor deposition mask parts. The intermediate product further includes a first plane and a second plane where open holes are formed, a pair of long side faces 26 connected to the first plane and the second plane for defining the contour of the vapor deposition mask parts in the longer direction of the vapor deposition mask parts, and a pair of short side faces 27 connected to the first plane and the second plane for defining the contour of the vapor deposition mask parts in the width direction of the vapor deposition mask parts. The long side faces have a first part dented inside that includes a first end part located on the first plane side and a second end part located on the second plane side and inside the first end part. The open holes include a first dented part of the first plane side and a second dented part formed on the second plane side and connected to the first dented part at a hole connection part. The first end part of the first part of the long side faces is located on the first plane side from the hole connection part.SELECTED DRAWING: Figure 22A

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to deposition masks and intermediate products. [Background technology]

[0002] In recent years, display devices used in portable devices such as smartphones and tablet PCs are required to have high definition, for example, a pixel density of 400 ppi or more. There is also an increasing demand for portable devices to support ultra full high definition, in which case the pixel density of the display device is required to be, for example, 800 ppi or more.

[0003] Among display devices, organic EL display devices have been attracting attention due to their good response, low power consumption, and high contrast. As a method for forming pixels of an organic EL display device, a method is known in which a deposition mask having through holes arranged in a desired pattern is used to form pixels in a desired pattern. Specifically, a deposition mask is first attached to a substrate for an organic EL display device, and then the attached deposition mask and the substrate are both placed in a deposition device to perform a deposition process in which an organic material is deposited on the substrate. This allows pixels containing an organic material to be formed on the substrate in a pattern corresponding to the pattern of the through holes of the deposition mask.

[0004] In the deposition process, the deposition mask is fixed to a frame having a predetermined rigidity, as disclosed in, for example, Patent Document 1. For example, when the deposition mask has a rectangular shape including a pair of long sides and a pair of short sides, the deposition mask is fixed to the frame in a state of being pulled in the direction of the long sides. This makes it possible to suppress bending of the deposition mask and to improve the dimensional accuracy and positional accuracy of pixels. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5382259 Summary of the Invention [Problem to be solved by the invention]

[0006] One factor that determines the positional accuracy of pixels formed on a substrate is the accuracy of alignment of a deposition mask with respect to a substrate or a frame. For example, the outline of the outer shape of the deposition mask is used as the reference position of the deposition mask during alignment. The position of the outline of the deposition mask is detected, for example, by photographing the deposition mask with a camera or the like.

[0007] In a step of detecting the position of the contour of a deposition mask based on an image captured by a camera or the like, it is preferable that the boundary between the deposition mask region and other regions is clearly shown in the image. However, if light scattering occurs in a portion that defines the contour of the deposition mask, the boundary between the deposition mask region and other regions becomes blurred in the image.

[0008] An object of the embodiments of the present disclosure is to provide an intermediate deposition mask that can effectively solve such problems. [Means for solving the problem]

[0009] a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a longitudinal direction of the deposition mask portion; and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a width direction of the deposition mask portion, the long side surfaces including a first end portion located on the first surface side and a second end portion located on the second surface side and located more inward than the first end portion, and having a first portion recessed inward, the through hole including a first recess formed on the first surface side and a second recess formed on the second surface side and connected to the first recess at a hole connecting portion, the first end portion of the first portion of the long side surface being located on the first surface side relative to the hole connecting portion. The first end may be a first connection portion that connects the first surface and the long side surface and is flush with the first surface, or the first end may be a first connection portion that connects the first surface and the long side surface and is flush with the first surface, and is located outside the first connection portion that connects the first surface and the long side surface and is flush with the first surface.

[0010] A second embodiment of the present disclosure is an intermediate product of a deposition mask, comprising: a plurality of deposition mask portions in which a plurality of through holes are formed; and a support portion surrounding the deposition mask portions in a plan view and partially connected to the deposition mask portions, the deposition mask portions comprising: a first surface and a second surface in which the through holes are formed; a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portions in a longitudinal direction of the deposition mask portions; and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portions in a width direction of the deposition mask portions, the long side surfaces including a first end portion located on the first surface side and a second end portion located on the second surface side and more inward than the first end portion, and having a first portion recessed inward, the first end portion being a first connection portion that connects the first surface and the long side surfaces and coinciding with a first connection portion located on the same plane as the first surface.

[0011] In an intermediate product according to an embodiment of the present disclosure, a first connection portion connecting the first surface and the long side surface, wherein the distance in the surface direction of the first surface between the first connection portion located on the same plane as the first surface and the first end portion of the first portion of the long side surface may be 3.5 μm or less.

[0012] In the intermediate product according to the first and second embodiments of the present disclosure, the first portion may be located inside an imaginary plane or line passing through the first end and the second end.

[0013] In the intermediate product according to the first and second embodiments of the present disclosure, the deposition mask may have a thickness of 50 μm or less.

[0014] In the intermediate products according to the first and second embodiments of the present disclosure, the second end may be a second connection portion where the second surface and the long side surface are connected, and may coincide with a second connection portion located on the same plane as the second surface. Effect of the Invention

[0015] According to the embodiment of the present disclosure, the contour of the deposition mask can be detected with high accuracy. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram showing a deposition apparatus including a deposition mask device according to an embodiment of the present disclosure. [Diagram 2] 2 is a cross-sectional view showing an organic EL display device manufactured using the deposition mask device shown in FIG. [Diagram 3] FIG. 1 is a plan view showing a deposition mask apparatus according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a perspective view showing a deposition mask. [Diagram 5] 4 is a partial plan view showing an effective area of ​​the deposition mask shown in FIG. 3. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 5. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 5. [Figure 9] 6 is an enlarged cross-sectional view showing the through hole and the area in its vicinity shown in FIG. 5. [Figure 10] FIG. 5 is a cross-sectional view taken along line XX in FIG. [Figure 11] FIG. 2 is a plan view showing the deposition mask as viewed from the first surface side. [Figure 12] FIG. 4 is a plan view showing the deposition mask as viewed from the second surface side. [Figure 13] 1A to 1C are schematic diagrams for generally explaining an example of a method for manufacturing a deposition mask. [Figure 14] 1A to 1C are diagrams illustrating a process of forming a resist film on a metal plate. [Figure 15] 1A to 1C are diagrams showing a process of closely adhering an exposure mask to a resist film. [Figure 16] 1A to 1C are diagrams illustrating a process of developing a resist film. [Figure 17] FIG. 11 is a diagram showing a first surface etching step. [Figure 18]13A and 13B are diagrams illustrating a step of covering the first recess with resin. [Figure 19] FIG. 11 is a diagram showing a second surface etching step. [Figure 20] FIG. 20 is a diagram showing a second surface etching step subsequent to FIG. 19 . [Figure 21] 1A to 1C are diagrams showing a process of removing the resin and the resist pattern from the metal plate. [Figure 22A] FIG. 2 is a plan view showing an intermediate product obtained by processing a metal plate. [Figure 22B] 22B is an enlarged view of the area surrounded by a dotted line and marked with the reference character XXIIB in the intermediate product of FIG. 22A. FIG. [Figure 23] 11A to 11C are diagrams illustrating a process of separating a deposition mask portion from a supporting portion. [Figure 24] FIG. 2 is an enlarged plan view showing a deposition mask obtained from an intermediate product. [Diagram 25] 1A to 1C are diagrams illustrating steps for fabricating a deposition mask device. [Figure 26] FIG. 11 is a cross-sectional view showing a modified example of the long side surface of the deposition mask. [Figure 27] 4 is a diagram showing the observation result of a cross section of a long side surface of the deposition mask according to Example 1. FIG. [Figure 28A] 28 is a diagram showing a result of observing the deposition mask shown in FIG. 27 from the first surface side. FIG. [Figure 28B] 28 is a diagram showing a result of observing the deposition mask shown in FIG. 27 from the second surface side. FIG. [Figure 29A] 13 is a diagram showing an observation result of a cross section of a long side surface of the deposition mask according to Example 2. FIG. [Figure 29B] 29B is an enlarged cross-sectional view of a second portion of the long side surface shown in FIG. 29A. FIG. [Diagram 30] FIG. 11 is a diagram showing the observation results of a cross section of a long side surface of the deposition mask according to Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings attached to this specification, the scale and the aspect ratio are appropriately changed and exaggerated from those of the actual objects for the convenience of illustration and understanding.

[0018] 1 to 25 are diagrams for explaining an embodiment of the present disclosure. In the following embodiment and its modified examples, a method for manufacturing a deposition mask used for patterning an organic material in a desired pattern on a substrate when manufacturing an organic EL display device will be described as an example. However, the application is not limited to such an application, and the embodiment of the present disclosure can be applied to deposition masks used for various purposes.

[0019] In this specification, the terms "plate," "sheet," and "film" are not distinguished from one another solely on the basis of differences in name. For example, the term "plate" is a concept that includes members that can be called sheets or films.

[0020] In addition, the term "plate surface (sheet surface, film surface)" refers to a surface that coincides with the planar direction of the target plate-like (sheet-like, film-like) member when the target plate-like (sheet-like, film-like) member is viewed overall and in a global perspective. In addition, the normal direction used for a plate-like (sheet-like, film-like) member refers to the normal direction to the plate surface (sheet surface, film surface) of the member.

[0021] Furthermore, terms used in this specification that specify shapes, geometric conditions, and physical characteristics, as well as the extent of these, such as "parallel," "orthogonal," "same," and "equivalent," as well as lengths, angles, and values ​​of physical characteristics, are not to be bound by their strict meanings, but are to be interpreted to include the range within which similar functions can be expected.

[0022] (evaporation equipment) First, a deposition apparatus 90 for performing a deposition process for depositing a deposition material on a target object will be described with reference to FIG. 1. As shown in FIG. 1, the deposition apparatus 90 includes an deposition source (e.g., a crucible 94), a heater 96, and a deposition mask device 10 therein. The deposition apparatus 90 further includes an exhaust means for creating a vacuum atmosphere inside the deposition apparatus 90. The crucible 94 contains a deposition material 98 such as an organic light-emitting material. The heater 96 heats the crucible 94 to evaporate the deposition material 98 under a vacuum atmosphere. The deposition mask device 10 is disposed to face the crucible 94.

[0023] (Deposition mask device) The deposition mask device 10 will be described below. As shown in FIG. 1, the deposition mask device 10 includes a deposition mask 20 and a frame 15 that supports the deposition mask 20. The frame 15 supports the deposition mask 20 in a state where the deposition mask 20 is pulled in the direction of its surface so that the deposition mask 20 does not bend. As shown in FIG. 1, the deposition mask device 10 is disposed in a deposition device 90 so that the deposition mask 20 faces a substrate, for example, an organic EL substrate 92, which is an object to which the deposition material 98 is to be attached. In the following description, of the surfaces of the deposition mask 20, the surface on the organic EL substrate 92 side is referred to as a first surface 20a, and the surface located opposite the first surface 20a is referred to as a second surface 20b, but is not limited thereto.

[0024] 1, the deposition mask device 10 may include a magnet 93 arranged on the surface of the organic EL substrate 92 opposite to the deposition mask 20. By providing the magnet 93, the deposition mask 20 can be attracted to the magnet 93 by magnetic force, and the deposition mask 20 can be closely attached to the organic EL substrate 92. This can suppress the generation of shadows in the deposition process, and can improve the dimensional accuracy and positional accuracy of the deposition material 98 attached to the EL substrate 92.

[0025] 3 is a plan view showing the deposition mask device 10 as viewed from the first surface 20a side of the deposition mask 20. As shown in FIG. 3, the deposition mask device 10 includes a plurality of deposition masks 20. In the present embodiment, each deposition mask 20 has a rectangular shape extending in a longitudinal direction D1. In the deposition mask device 10, the plurality of deposition masks 20 are arranged in a width direction D2 intersecting with the longitudinal direction D1 of the deposition mask 20. Each deposition mask 20 is fixed to a frame 15 at both ends of the deposition mask 20 in the longitudinal direction D1 by, for example, welding.

[0026] 4 is a perspective view showing the deposition mask 20. The deposition mask 20 includes a metal plate-shaped base material 21 and a plurality of through-holes 25 penetrating the base material 21. The deposition material 98 that has evaporated from the crucible 94 and reached the deposition mask device 10 passes through the through-holes 25 of the deposition mask 20 and adheres to the organic EL substrate 92. This allows the deposition material 98 to be formed into a film on the surface of the organic EL substrate 92 in a desired pattern corresponding to the positions of the through-holes 25 of the deposition mask 20.

[0027] Fig. 2 is a cross-sectional view showing an organic EL display device 100 manufactured using the deposition apparatus 90 of Fig. 1. The organic EL display device 100 includes an organic EL substrate 92 and pixels including a deposition material 98 provided in a pattern.

[0028] When a color display using a plurality of colors is desired, deposition apparatuses 90 each equipped with a deposition mask 20 corresponding to each color are prepared, and the organic EL substrates 92 are sequentially placed in each deposition apparatus 90. In this way, for example, a red organic light-emitting material, a green organic light-emitting material, and a blue organic light-emitting material can be sequentially deposited on the organic EL substrate 92.

[0029] Incidentally, the deposition process may be performed inside a deposition apparatus 90 in a high-temperature atmosphere. In this case, the deposition mask 20, the frame 15, and the organic EL substrate 92 held inside the deposition apparatus 90 are also heated during the deposition process. At this time, the deposition mask 20, the frame 15, and the organic EL substrate 92 exhibit dimensional change behavior based on their respective thermal expansion coefficients. In this case, if the thermal expansion coefficients of the deposition mask 20 or the frame 15 and the organic EL substrate 92 are significantly different from each other, positional deviation occurs due to the difference in dimensional change, and as a result, the dimensional accuracy and positional accuracy of the deposition material attached to the organic EL substrate 92 are reduced.

[0030] In order to solve such a problem, it is preferable that the thermal expansion coefficients of the deposition mask 20 and the frame 15 are equal to that 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 the main material of the deposition mask 20 and the frame 15. For example, an iron alloy containing 30% by mass or more and 54% by mass or less of nickel can be used as the material of the base material constituting the deposition mask 20. Specific examples of the iron alloy containing nickel include an Invar material containing 34% by mass or more and 38% by mass or less of nickel, a Super Invar material containing 30% by mass or more and 34% by mass or less of nickel and further containing cobalt, and a low thermal expansion Fe-Ni-based plating alloy containing 38% by mass or more and 54% by mass or less of nickel.

[0031] If the temperatures of the deposition mask 20, the frame 15, and the organic EL substrate 92 do not reach high temperatures during deposition, there is no particular need to set the thermal expansion coefficients of the deposition mask 20 and the frame 15 to values ​​equivalent to the thermal expansion coefficient of the organic EL substrate 92. In this case, a material other than the iron alloy described above may be used as a material constituting the deposition mask 20. For example, an iron alloy other than the iron alloy containing nickel described above, such as an iron alloy containing chromium, may be used. As the iron alloy containing chromium, for example, an iron alloy so-called stainless steel may be used. In addition, an alloy other than the iron alloy, such as nickel or a nickel-cobalt alloy, may be used.

[0032] (Deposition mask) Next, the deposition mask 20 will be described in detail. First, the outer shape of the deposition mask 20 will be described. As shown in FIG. 3 and FIG. 4, the deposition mask 20 includes the first surface 20a and the second surface 20b in which the through-holes 25 are formed, and a pair of long side surfaces 26 and a pair of short side surfaces 27 connected to the first surface 20a and the second surface 20b. The pair of long side surfaces 26 extend in the longitudinal direction D1 of the deposition mask 20. When the deposition mask 20 is viewed along the normal direction of the first surface 20a, the pair of long side surfaces 26 define the contour of the deposition mask 20 in the longitudinal direction D1. The pair of short side surfaces 27 extend in the width direction D2 of the deposition mask 20. When the deposition mask 20 is viewed along the normal direction of the first surface 20a, the pair of short side surfaces 27 define the contour of the deposition mask 20 in the width direction D2. In the example shown in FIG. 3 and FIG. 4, the width direction D2 is perpendicular to the longitudinal direction D1. In the following description, the portion where the first surface 20a and the long side surface 26 are connected is referred to as the first connection portion 20e, and the portion where the second surface 20b and the long side surface 26 are connected is referred to as the second connection portion 20f. The first connection portion 20e is located on the same plane as the first surface 20a. The second connection portion 20f is located on the same plane as the second surface 20b.

[0033] Next, a configuration of the deposition mask 20 related to the through-hole 25 will be described. As shown in Fig. 3 and Fig. 4, the deposition mask 20 includes at least one effective area 22 in which a through-hole 25 extending from the first surface 20a to the second surface 20b is formed, and a surrounding area 23 surrounding the effective area 22. The effective area 22 is an area of ​​the deposition mask 20 that faces the display area of ​​the organic EL substrate 92.

[0034] 3 and 4, the deposition mask 20 includes a plurality of effective areas 22 arranged at predetermined intervals along the longitudinal direction D1 of the deposition mask 20. One effective area 22 corresponds to the display area of ​​one organic EL display device 100. This enables multi-surface deposition of the organic EL display device 100. That is, using one deposition mask 20, patterns of the deposition material 98 corresponding to a plurality of organic EL display devices 100 can be formed on one organic EL substrate 92.

[0035] 3 and 4, the effective area 22 has, for example, a substantially quadrangular outline in a plan view, more precisely, a substantially rectangular outline in a plan view. Although not shown, each effective area 22 can have an outline 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.

[0036] [Effective area] The cross-sectional shape of the effective area 22 will be described in detail below. Fig. 5 is an enlarged plan view of the effective area 22 as viewed from the second surface 20b side of the deposition mask 20. As shown in Fig. 5, in the illustrated example, a plurality of through holes 25 formed in each effective area 22 are arranged at a predetermined pitch along two directions perpendicular to each other in the effective area 22. An example of the through holes 25 will be described in further detail mainly with reference to Figs. 6 to 8. Figs. 6 to 8 are cross-sectional views along the VI-VI direction to the VIII-VIII direction of the effective area 22 in Fig. 5, respectively.

[0037] As shown in FIGS. 6 to 8, the multiple through holes 25 penetrate from a first surface 20a, which is one side of the deposition mask 20 along the normal direction N, to a second surface 20b, which is the other side of the deposition mask 20 along the normal direction N. In the illustrated example, as described in detail later, a first recess 30 is formed in the first surface 20a of the deposition mask 20 by etching, and a second recess 35 is formed in the second surface 20b of the deposition mask 20. The first recess 30 is connected to the second recess 35, and the second recess 35 and the first recess 30 are formed to communicate with each other. The through hole 25 is composed of the second recess 35 and the first recess 30 connected to the second recess 35.

[0038] 6 to 8, the opening area of ​​each of the second recesses 35 in a cross section along the plate surface of the deposition mask 20 at each position along the normal direction N of the deposition mask 20 gradually decreases from the second surface 20b side to the first surface 20a side of the deposition mask 20. Similarly, the opening area of ​​each of the first recesses 30 in a cross section along the plate surface of the deposition mask 20 at each position along the normal direction N of the deposition mask 20 gradually decreases from the first surface 20a side to the second surface 20b side of the deposition mask 20.

[0039] 6 to 8, the wall surface 31 of the first recess 30 and the wall surface 36 of the second recess 35 are connected via a circumferential hole connecting portion 41. The hole connecting portion 41 is defined by a ridgeline of a protruding portion where the wall surface 31 of the first recess 30, which is inclined with respect to the normal direction N of the deposition mask 20, and the wall surface 36 of the second recess 35, which is inclined with respect to the normal direction N of the deposition mask 20, join together. The hole connecting portion 41 defines a through portion 42 where the opening area of ​​the through hole 25 is minimized in a plan view of the deposition mask 20.

[0040] 6 to 8, on the first surface 20a of the deposition mask 20, two adjacent through holes 25 are spaced apart from each other along the plate surface of the deposition mask 20. That is, when the first recesses 30 are formed by etching the base material 21 from the first surface 20a side of the deposition mask 20 as in the manufacturing method described later, the first surface 20a remains between the two adjacent first recesses 30.

[0041] Similarly, as shown in FIG. 6 and FIG. 8, on the second surface 20b side of the deposition mask 20, two adjacent second recesses 35 may be spaced apart from each other along the plate surface of the deposition mask 20. That is, the second surface 20b of the deposition mask 20 may remain between two adjacent second recesses 35. In the following description, a portion of the effective area 22 of the second surface 20b of the deposition mask 20 that is not etched and remains is also referred to as a top portion 43. By producing the deposition mask 20 so that such a top portion 43 remains, the deposition mask 20 can have sufficient strength. This makes it possible to prevent the deposition mask 20 from being damaged, for example, during transportation. If the width β of the top portion 43 is too large, a shadow may be generated in the deposition process, which may reduce the utilization efficiency of the deposition material 98. Therefore, it is preferable that the deposition mask 20 is produced so that the width β of the top portion 43 is not excessively large. For example, it is preferable that the width β of the top portion 43 is 2 μm or less. The width β of the top portion 43 generally changes depending on the direction in which the deposition mask 20 is cut. For example, the width β of the top portion 43 shown in Fig. 6 and Fig. 8 may be different from each other. In this case, the deposition mask 20 may be configured so that the width β of the top portion 43 is 2 µm or less in any direction when the deposition mask 20 is cut. Note that the shadow refers to a phenomenon in which a part of the deposition material 98 that has reached the deposition mask 20 from the deposition source collides with the wall surface 31 of the first recess 30 or the wall surface 36 of the second recess 35 of the deposition mask 20 and cannot reach a substrate such as the organic EL substrate 92, resulting in an insufficient area or thickness of the layer of the deposition material 98 on the substrate.

[0042] 7, etching may be performed so that two adjacent second recesses 35 are connected in some places. That is, there may be a place where no second surface 20b remains between two adjacent second recesses 35. Although not shown, etching may be performed so that two adjacent second recesses 35 are connected over the entire area of ​​second surface 20b.

[0043] When the deposition mask device 10 is accommodated in the deposition device 90 as shown in FIG. 1, the first surface 20a of the deposition mask 20 faces the organic EL substrate 92, and the second surface 20b of the deposition mask 20 is located on the side of the crucible 94 holding the deposition material 98. Therefore, the deposition material 98 passes through the second recess 35, the opening area of ​​which gradually decreases, and adheres to the organic EL substrate 92. As shown by the arrow from the second surface 20b side to the first surface 20a in FIG. 6, the deposition material 98 not only moves from the crucible 94 toward the organic EL substrate 92 along the normal direction N of the organic EL substrate 92, but also moves in a direction greatly inclined with respect to the normal direction N of the organic EL substrate 92. At this time, if the thickness of the deposition mask 20 is large, most of the deposition material 98 moving obliquely reaches and adheres to the wall surface 36 of the second recess 35 before passing through the through-hole 25 and reaching the organic EL substrate 92. Therefore, in order to increase the utilization efficiency of the deposition material 98, it is preferable to reduce the thickness t of the deposition mask 20, thereby reducing the height of the wall surface 36 of the second recess 35 and the wall surface 31 of the first recess 30. That is, it can be said that it is preferable to reduce the thickness t of the substrate 21 for constituting the deposition mask 20 as much as possible within a range in which the strength of the deposition mask 20 can be ensured. In consideration of this point, in the present embodiment, the thickness t of the deposition mask 20 is preferably set to 50 μm or less, for example, 5 μm or more and 50 μm or less. The thickness t of the deposition mask 20 may be 30 μm or less, 25 μm or less, 20 μm or less, 18 μm or less, 15 μm or less, or 13 μm or less. By reducing the thickness t of the deposition mask 20, it is possible to suppress the deposition material 98 from colliding with the wall surface 31 of the first recess 30 and the wall surface 36 of the second recess 35 in the deposition process, and therefore it is possible to suppress the occurrence of a shadow. The thickness of the metal plate 64 may be 2 μm or more, 5 μm or more, 10 μm or more, or 15 μm or more. The thickness t is the thickness of the surrounding region 23, that is, the thickness of the portion of the deposition mask 20 where the first recesses 30 and the second recesses 35 are not formed. Therefore, it can also be said that the thickness t is the thickness of the base material 21.In addition, it can also be said that the thickness t is the thickness of the metal plate 64 that constitutes the base material 21 of the deposition mask 20.

[0044] 6, the minimum angle that a straight line L1 passing through the hole connecting portion 41, which is the portion having the minimum opening area of ​​the through-hole 25, and any other position on the wall surface 36 of the second recess 35 forms with the normal direction N of the deposition mask 20 is denoted by θ1. In order to allow the deposition material 98 moving obliquely to reach the organic EL substrate 92 as far as possible without reaching the wall surface 36, it is advantageous to increase the angle θ1. In order to increase the angle θ1, it is also effective to reduce the width β of the top portion 43 described above, in addition to reducing the thickness t of the deposition mask 20.

[0045] 8, the symbol α represents the width of a portion (hereinafter also referred to as a rib portion) that remains unetched in the effective region 22 of the first surface 20a of the deposition mask 20. The width α of the rib portion and the dimension r2 of the through portion 42 are appropriately determined according to the dimensions and the number of display pixels of the organic EL display device. For example, the width α of the rib portion is 5 μm or more and 40 μm or less, and the dimension r2 of the through portion 42 is 10 μm or more and 60 μm or less.

[0046] Although not limited thereto, the deposition mask 20 according to the present embodiment is particularly effective in producing an organic EL display device having a pixel density of 450 ppi or more. Hereinafter, an example of the dimensions of the deposition mask 20 required for producing an organic EL display device having such a high pixel density will be described with reference to Fig. 9. Fig. 9 is an enlarged cross-sectional view showing the through-hole 25 of the deposition mask 20 shown in Fig. 6 and a region in the vicinity thereof.

[0047] 9, as a parameter related to the shape of the through-hole 25, the distance from the first surface 20a of the deposition mask 20 to the hole connecting portion 41 in the direction along the normal direction N of the deposition mask 20, i.e., the height of the wall surface 31 of the first recess 30, is represented by symbol r1. Furthermore, the dimension of the first recess 30 at the portion where the first recess 30 is connected to the second recess 35, i.e., the dimension of the through portion 42, is represented by symbol r2. Also in FIG. 9, the angle that a straight line L2 connecting the hole connecting portion 41 and the tip edge of the first recess 30 on the first surface 20a of the deposition mask 20 makes with respect to the normal direction N of the substrate 21 is represented by symbol θ2.

[0048] When an organic EL display device with a pixel density of 450 ppi or more is manufactured, the dimension r2 of the through portion 42 is preferably set to 10 μm or more and 60 μm or less. This makes it possible to provide a deposition mask 20 that can manufacture an organic EL display device with high pixel density. Preferably, the height r1 of the wall surface 31 of the first recess 30 is set to 6 μm or less.

[0049] Next, the angle θ2 shown in FIG. 9 will be described. The angle θ2 corresponds to the maximum value of the inclination angle of the deposition material 98 that is inclined with respect to the normal direction N of the base material 21 and that can reach the organic EL substrate 92 among the deposition material 98 that has flown to pass through the through-hole portion 42 near the hole connection portion 41. This is because the deposition material 98 that has flown through the hole connection portion 41 at an inclination angle larger than the angle θ2 adheres to the wall surface 31 of the first recess 30 before reaching the organic EL substrate 92. Therefore, by reducing the angle θ2, it is possible to prevent the deposition material 98 that has flown at a large inclination angle and passed through the through-hole portion 42 from adhering to the organic EL substrate 92, and thus it is possible to prevent the deposition material 98 from adhering to a portion of the organic EL substrate 92 that is outside the portion that overlaps with the through-hole portion 42. In other words, reducing the angle θ2 leads to suppression of variations in the area and thickness of the deposition material 98 that adheres to the organic EL substrate 92. From this viewpoint, for example, the through-hole 25 is formed so that the angle θ2 is 45 degrees or less. 9 shows an example in which the dimension of the first recess 30 in the first surface 20a, i.e., the opening dimension of the through hole 25 in the first surface 20a, is larger than the dimension r2 of the first recess 30 in the hole connecting portion 41. That is, an example in which the value of the angle θ2 is a positive value is shown. However, although not shown, the dimension r2 of the first recess 30 in the hole connecting portion 41 may be larger than the dimension of the first recess 30 in the first surface 20a. That is, the value of the angle θ2 may be a negative value.

[0050] [Surrounding Area] Next, the cross-sectional shape of the peripheral region 23 will be described in detail. FIG. 10 is a cross-sectional view of the deposition mask 20 cut along the line XX in FIG. 4. As shown in FIG. 10, the long side surface 26 constituting the end of the peripheral region 23 has a first portion 261 which is a surface recessed inward. In the present embodiment, the first portion 261 is a curved surface curved to recess inward. The first portion 261 includes a first end portion 261a which defines the outline of the first portion 261 on the first surface 20a side and a second end portion 261b which defines the outline of the first portion 261 on the second surface 20b side when the long side surface 26 is viewed from the outside along the surface direction of the first surface 20a. When the term "inner side" is used with respect to the long side surface 26, the "inner side" means the center side in the width direction D2 of the deposition mask 20, as indicated by an arrow A1 in FIG. 10 and FIG. 22B described later. The "center side" means the side of the center line C passing through the midpoint of the deposition mask 20 in the width direction D2, as shown in FIG. 4 and FIG. 10. The "outside" means the side away from the center line C of the deposition mask 20 in the width direction D2 of the deposition mask 20, as shown by an arrow A2 in FIG. 10 and FIG. 22B described later. The "inwardly recessed" means that the first portion 261 is located inside a virtual straight line or plane connecting the first end 261a on the first surface 20a side of the first portion 261 and the second end 261b on the second surface 20b side of the first portion 261. Although not shown, the first portion 261 may include a flat surface. That is, the first portion 261 may not be composed of only a curved surface. The first portion 261 may locally include an uneven surface such as a zigzag surface.

[0051] 10, the first end 261a of the first portion 261 is located outside the second end 261b. As described later, the first portion 261 is formed by etching the metal plate constituting the base material 21 from the second surface 20b side. A distance γ between the first end 261a and the second end 261b in the width direction D2 is, for example, 5 μm or more and 50 μm or less.

[0052] In the example shown in Fig. 10, the second end 261b of the first portion 261 coincides with the second connection portion 20f where the second surface 20b and the long side surface 26 are connected. In other words, the first portion 261 extends to the second surface 20b. Also, in the example shown in Fig. 10, the first end 261a of the first portion 261 coincides with the first connection portion 20e where the first surface 20a and the long side surface 26 are connected. In other words, the first portion 261 extends to the first surface 20a.

[0053] Next, the shape of the long side surface 26 in a plan view will be described. Fig. 11 is a plan view showing the long side surface 26 as viewed from the first surface 20a side along the normal direction of the first surface 20a. Fig. 12 is a plan view showing the long side surface 26 as viewed from the second surface 20b side along the normal direction of the second surface 20b.

[0054] 11, when the long side surface 26 is viewed from the first surface 20a side, the first portion 261 is not visible. In this case, the outline of the deposition mask 20 in the longitudinal direction D1 is defined by the first connection portion 20e that connects the first surface 20a and the long side surface 26. In this case, the region near the first connection portion 20e is configured by the flat first surface 20a. For this reason, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be easily detected.

[0055] On the other hand, as is clear from FIG. 12, when the long side surface 26 is viewed from the second surface 20b side, the first portion 261 is visible. In the first portion 261, light is scattered in various directions. Therefore, in the example shown in FIG. 12, the first portion 261 is viewed or appears in an image as a portion that looks black compared to the second surface 20b. In addition, the first portion 261 has a width corresponding to the distance γ in FIG. 10. Therefore, there is an uncertainty corresponding to the width of the first portion 261 in the position of the outline of the deposition mask 20 when viewed from the second surface 20b side. Therefore, it is more difficult to detect the position of the outline of the deposition mask 20 in the longitudinal direction D1 when viewed from the second surface 20b side than when viewed from the first surface 20a side. Therefore, in the process of aligning the deposition mask 20 with respect to the organic EL substrate 92 or the frame 15, the adjustment is facilitated and the alignment accuracy is improved by adjusting the position of the deposition mask 20 based on the results of photographing the deposition mask 20 from the first surface 20a side.

[0056] Method for manufacturing deposition mask Next, a method for manufacturing the deposition mask 20 will be described.

[0057] (Preparation of metal plate) First, a metal plate 64 for manufacturing a deposition mask is prepared. The metal plate 64 is prepared in the form of a roll obtained by winding up a long metal plate, for example. As the metal plate 64, for example, a metal plate made of an iron alloy containing nickel is used. The thickness of the metal plate 64 is, for example, 5 μm or more and 50 μm or less. A rolling method, a plating film formation method, or the like can be adopted as a method for manufacturing the metal plate 64 having a desired thickness.

[0058] Next, a method for manufacturing the deposition mask 20 using the metal plate 64 will be described mainly with reference to Fig. 13 to Fig. 24. In the method for manufacturing the deposition mask 20 described below, as shown in Fig. 13, the metal plate 64 is processed to form a plurality of deposition mask portions, each including a through-hole 25, in the metal plate 64 (processing step), and then the deposition mask portions are separated from the metal plate 64 (separation step), thereby obtaining a sheet-like deposition mask 20.

[0059] (Processing process) The process of processing the metal plate 64 includes a process of etching the long metal plate 64 using a photolithography technique to form a first recess 30 on the metal plate 64 from the first surface 64a side, and a process of etching the metal plate 64 using a photolithography technique to form a second recess 35 on the metal plate 64 from the second surface 64b side. The first recess 30 and the second recess 35 formed on the metal plate 64 communicate with each other, thereby forming a through hole 25 in the metal plate 64. In the example described below, the process of forming the first recess 30 is performed before the process of forming the second recess 35, and a process of sealing the first recess 30 formed is performed between the process of forming the first recess 30 and the process of forming the second recess 35. Each process will be described in detail below.

[0060] Fig. 13 shows a manufacturing apparatus 60 for producing the deposition mask 20. As shown in Fig. 13, first, a wound body 62 is prepared by winding a metal plate 64 around a core 61. Then, the core 61 is rotated to unwind the wound body 62, thereby supplying a metal plate 64 extending in a band shape as shown in Fig. 13.

[0061] The supplied metal plate 64 is transported to a processing device (etching means) 70 by a transport roller 72. The processing device 70 performs each of the processes shown in Figs. 14 to 21. In this embodiment, a plurality of deposition masks 20 are allocated in the width direction of the metal plate 64. In other words, the metal plate 64 is processed so that a plurality of deposition mask portions, which will be described later and which are separated from the metal plate 64 to become deposition masks 20, are arranged in the width direction of the metal plate 64. In this case, the plurality of deposition masks 20 are preferably allocated to the metal plate 64 so that the direction of the deposition mask portions, i.e., the long side surfaces 26 of the deposition masks 20, coincides with the longitudinal direction of the elongated metal plate 64.

[0062] 14, resist films 65c, 65d containing a negative photosensitive resist material are formed on the first surface 64a and the second surface 64b of the metal plate 64. For example, a coating liquid containing a negative photosensitive resist material is applied onto the first surface 64a and the second surface 64b of the metal plate 64, and then the coating liquid is dried to form the resist films 65c, 65d.

[0063] Next, exposure masks 68a and 68b that do not transmit light to the regions of the resist films 65c and 65d that are to be removed are prepared, and the exposure masks 68a and 68b are placed on the resist films 65c and 65d, respectively, as shown in Fig. 15. For the exposure masks 68a and 68b, for example, glass dry plates that do not transmit light to the regions of the resist films 65c and 65d that are to be removed are used. Thereafter, the exposure masks 68a and 68b are sufficiently attached to the resist films 65c and 65d by vacuum contact. A positive photosensitive resist material may be used, in which case an exposure mask is used that allows light to pass through the area of ​​the resist film that is to be removed.

[0064] Thereafter, the resist films 65c, 65d are exposed through exposure masks 68a, 68b (exposure process). Furthermore, the resist films 65c, 65d are developed to form an image on the exposed resist films 65c, 65d (development process). In this manner, as shown in FIG. 16, a first resist pattern 65a can be formed on the first surface 64a of the metal plate 64, and a second resist pattern 65b can be formed on the second surface 64b of the metal plate 64. The development process may include a resist heat treatment process for increasing the hardness of the resist films 65c, 65d or for more firmly adhering the resist films 65c, 65d to the metal plate 64. The resist heat treatment process may be performed, for example, at room temperature or higher and 400° C. or lower. In FIG. 16 and FIGS. 17 to 21 described later, the manufacturing process of the effective region 22 is shown on the right side, and the manufacturing process of the peripheral region 23 is shown on the left side.

[0065] As shown in FIG. 16, the first resist pattern 65a provided in the effective region 22 has a hole 66a located in a portion of the first surface 64a where the first recess 30 will be formed later. On the other hand, the first resist pattern 65a provided in the peripheral region 23 covers a portion of the first surface 64a that will become the long side surface 26 later. The second resist pattern 65b has a hole 66b located in a portion of the second surface 64b of the effective region 22 where the second recess 35 will be formed later, and has an opening 66d located in a portion of the second surface 64b of the peripheral region 23 that will become the long side surface 26 later. The dimension M2 of the opening 66d is larger than the dimension M1 of the hole 66b. The dimension M2 of the opening 66d is, for example, 50 μm or more.

[0066] Next, as shown in FIG. 17, a first surface etching step is performed in which the area of ​​the first surface 64a of the metal plate 64 that is not covered by the first resist pattern 65a is etched using a first etching liquid. For example, the first etching liquid is sprayed toward the first surface 64a of the metal plate 64 through the first resist pattern 65a from a nozzle arranged on the side facing the first surface 64a of the transported metal plate 64. As a result, as shown in FIG. 17, the area of ​​the first surface 64a of the metal plate 64 that corresponds to the hole 66a is eroded by the first etching liquid. As a result, a large number of first recesses 30 are formed on the first surface 64a of the metal plate 64. As the first etching liquid, for example, one containing a ferric chloride solution and hydrochloric acid is used. As described above, the first resist pattern 65a provided in the surrounding area 23 covers the part of the first surface 64a that will later become the long side surface 26. Therefore, the first recesses 30 are not formed on the part of the first surface 64a that will later become the long side surface 26.

[0067] 18, the first recess 30 is covered with a resin 69 having resistance to a second etching liquid used in a subsequent second surface etching step. That is, the first recess 30 is sealed with the resin 69 having resistance to the second etching liquid. In the example shown in FIG. 18, the film of the resin 69 is formed so as to cover not only the formed first recess 30 but also the first surface 64a (first resist pattern 65a).

[0068] Next, as shown in FIG. 19, a second-side etching step is performed in which the regions of the second surface 64b of the metal plate 64 corresponding to the holes 66b and the openings 66d are etched to form the second recesses 35 on the second surface 64b. FIG. 20 is a diagram showing a state in which the second-side etching step has progressed further. As shown in FIG. 20, in the region of the metal plate 64 corresponding to the effective region 22, the second-side etching step is performed until the first recesses 30 and the second recesses 35 communicate with each other, thereby forming the through-holes 25. On the other hand, in the region of the metal plate 64 corresponding to the peripheral region 23, the second-side etching step is performed until the second recesses 35 reach the first surface 64a. As described above, the dimension M2 of the openings 66d of the second resist pattern 65b located in the peripheral region 23 is larger than the dimension M1 of the holes 66b of the second resist pattern 65b located in the effective region 22. Therefore, as shown in FIG. 20, etching in the thickness direction of the metal plate 64 can be made to proceed faster in the peripheral region 23 than in the effective region 22. As the second etching solution, similar to the above-mentioned first etching solution, for example, one containing a ferric chloride solution and hydrochloric acid is used.

[0069] The second etching liquid corrodes the portion of the metal plate 64 that is in contact with the second etching liquid. Therefore, the corrosion does not proceed only in the normal direction N (thickness direction) of the metal plate 64, but also in a direction along the plate surface of the metal plate 64. Preferably, in the region of the metal plate 64 corresponding to the effective region 22, the second surface etching step is terminated before the two second recesses 35 formed at positions facing the two adjacent holes 66a of the second resist pattern 65b join on the back side of the second resist pattern 65b located between the two holes 66a. This allows the above-mentioned top portion 43 to remain on the second surface 64b of the metal plate 64, as shown in FIG. 20.

[0070] Thereafter, as shown in Fig. 21, resin 69 is removed from metal plate 64. Resin 69 can be removed by using, for example, an alkaline stripper. When an alkaline stripper is used, resist patterns 65a, 65b are also removed at the same time as resin 69, as shown in Fig. 21. After resin 69 is removed, resist patterns 65a, 65b may be removed separately from resin 69 using a stripper different from the stripper for stripping resin 69.

[0071] 21, in a region of the metal plate 64 corresponding to the peripheral region 23, the second recess 35 reaches the first surface 64a, thereby forming a long side surface 26 separated from other portions of the metal plate 64 in the width direction D2. The long side surface 26 includes a first portion 261 based on the second recess 35 formed in the second surface 64b of the metal plate 64 corresponding to the opening 66d of the second resist pattern 65b. In this case, a first end portion 261a of the first portion 261 coincides with a first connection portion 20e where the long side surface 26 and the first surface 64a (first surface 20a) are connected.

[0072] 22A is a plan view showing an intermediate product 50 obtained by processing the deposition mask 20 to form the through-holes 25 as described above. The intermediate product 50 includes a plurality of deposition mask portions 51 and a supporting portion 56. The conveying direction of the metal plate 64 in the manufacturing process of the deposition mask 20 coincides with the longitudinal direction D1.

[0073] The deposition mask portions 51 are portions of the metal plate 64 that become the deposition masks 20 when separated. As shown in Fig. 22A, the deposition mask portions 51 are arranged in the width direction D2.

[0074] The supporting portions 56 are portions that surround the multiple deposition mask portions 51 in a plan view and are partially connected to the deposition mask portions 51. In the example shown in Fig. 22A, the supporting portions 56 are portions of the metal plate 64 other than the deposition mask portions 51. As shown in Fig. 22A, the deposition mask portions 51 are connected to the supporting portions 56 via connection portions 54 on the short side surfaces 27.

[0075] FIG. 22B is an enlarged view of the area surrounded by the dotted line and marked with the symbol XXIIB in the intermediate product 50 in FIG. 22A. At the above-mentioned connection portion 54, the short side surface 27 of the deposition mask portion 51 includes a plurality of protruding portions 53a that protrude toward the support portion 56 and are connected to the support portion 56. For example, between the short side surface 27 and the support portion 56 of the intermediate product 50, a plurality of second through-portions 55b that penetrate the metal plate 64 are arranged along the direction in which the short side surface 27 extends. The dimension K of the second through-portion 55b in the width direction D2 is, for example, 30 μm or more and, for example, 100 μm or less. The protruding portion 53a is located between two adjacent second through-portions 55b in the direction in which the short side surface 27 extends. On the other hand, the long side surface 26 of the deposition mask portion 51 is not connected to the support portion 56. In other words, between the long side surface 26 of the deposition mask portion 51 of the intermediate product 50 and the support portion 56, the first penetrating portion 55a penetrating the metal plate 64 extends along the extending direction of the long side surface 26. The dimension S of the first penetrating portion 55a in the width direction D2 is, for example, 0.1 mm or more and, for example, 5 mm or less.

[0076] The first penetrating portion 55a constituting the long side surface 26 is formed by performing the second-surface etching process until the second recess 35 reaches the first surface 64a, as described above. In this case, the first end 261a of the first portion 261 included in the long side surface 26 formed by the second-surface etching process is positioned on the first surface 64a of the metal plate 64. That is, the first end 261a of the first portion 261 coincides with the first connection portion 20e that connects the first surface 20a of the deposition mask 20 and the long side surface 26.

[0077] The second penetrating portion 55b constituting the short side 27, like the first penetrating portion 55a constituting the long side 26, can be formed by performing a second surface etching process until the second recess 35 reaches the first surface 64a.

[0078] The fact that the first through portion 55a and the second through portion 55b are formed by performing the second surface etching step until the second recess 35 reaches the first surface 64a means that the first through portion 55a and the second through portion 55b do not include the first recess 30 connected to the second recess 35. Hereinafter, the advantage of the first through portion 55a and the second through portion 55b not including the first recess 30 will be described.

[0079] After the first-side etching step, the metal plate 64 is transported to a location where the second-side etching step is performed. At this time, if the first recess 30 is formed in the portion of the metal plate 64 where the long side surface 26 or the short side surface 27 will be formed later in the first-side etching step, the metal plate 64 may break from the first recess 30 during transportation. The first recess 30 formed in the portion where the long side surface 26 will be formed has the same dimension as the deposition mask 20 in the longitudinal direction D1, and is therefore particularly likely to become a break starting point.

[0080] In contrast, in the present embodiment, the first through portion 55a or the second through portion 55b does not include the first recess 30. Therefore, in the first-side etching step, the first recess 30 is not formed in the portion of the metal plate 64 where the long side surface 26 or the short side surface 27 will be formed later. This makes it possible to suppress the occurrence of transportation defects such as bending of the metal plate 64 when the metal plate 64 is transported to the location where the second-side etching step is performed after the first-side etching step.

[0081] Furthermore, the fact that the first recess 30 is not formed means that the step of covering the first recess 30 with resin 69 is also unnecessary. If the first recess 30 were formed in the portion where the long side surface 26 is formed, the dimension would be larger than the dimension of the first recess 30 constituting the through hole 25, and therefore the cost and labor required for covering with resin 69 would also be large. In contrast, according to the present embodiment, the first through portion 55a or the second through portion 55b does not include the first recess 30, and therefore the cost and labor required for covering with resin 69 can be reduced.

[0082] (separation process) Next, a separation step is performed to separate the deposition mask portion 51 from the support portion 56 in the intermediate product 50. First, as shown in FIG. 13, the intermediate product 50 obtained by processing the metal plate 64 is transported to a separation device 73 for performing the separation step. For example, the intermediate product 50 is transported to the separation device 73 by transport rollers 72, 72 that rotate while sandwiching the intermediate product 50. However, if the long side surface 26 of the deposition mask portion 51 in the intermediate product 50 is not connected to the support portion 56, the deposition mask portion 51 is likely to shake or bend during transportation. In consideration of this point, a suppression means for suppressing the shaking or bending of the deposition mask portion 51 may be provided in the intermediate product 50, the transport roller 72, or the transport path. For example, the suppression means includes a pair of films provided on the first surface side and the second surface side of the intermediate product 50. By transporting the intermediate product 50 to the separation device 73 while sandwiching the intermediate product 50 between the pair of films, it is possible to suppress the deposition mask portion 51 from shaking or bending.

[0083] 23 is a diagram showing a separation step of separating the deposition mask portion 51 from the support portion 56. As described above, the long side surface 26 of the deposition mask portion 51 is not connected to the support portion 56. Therefore, by breaking the connection portion 54 between the deposition mask portion 51 and the support portion 56 at the short side surface 27, the deposition mask portion 51 can be separated from the support portion 56 to obtain the deposition mask 20. FIG. 24 is an enlarged plan view showing the deposition mask 20 obtained from the intermediate product 50.

[0084] The separation step includes, for example, a breaking step of breaking a connection portion 54 of the short side surface 27 of the deposition mask portion 51 that is connected to the support portion 56. In this case, as shown in FIG. 24 , a portion of the deposition mask 20 where the connection portion 54 is broken, for example, a tip of a protrusion 27a of the short side surface 27, becomes a fractured surface 27b. The fractured surface 27b is a surface on which burrs exist due to the force received from the support portion 56 at the time of breaking. On the other hand, no fractured surface exists on the long side surface 26.

[0085] In FIG. 24, the symbol ε represents the shortest distance in the surface direction of the base material 21 from the first connection portion 20e where the long side surface 26 and the first surface 20a are connected to the through hole 25. The distance ε is smaller than the shortest distance in the surface direction of the base material 21 from the connection portion where the short side surface 27 and the first surface 20a are connected to the through hole 25. Therefore, if deformation such as a wavy shape appears on the long side surface 26, the dimensional accuracy and positional accuracy of the deposition material 98 that adheres to the organic EL substrate 92 through the through hole 25 located near the long side surface 26 will decrease. Here, in this embodiment, the long side surface 26 is not connected to the support portion 56. Therefore, during the separation process of separating the deposition mask portion 51 from the support portion 56, the long side surface 26 does not receive a force from the support portion 56, so that it is possible to suppress the occurrence of deformation such as a wavy shape on the long side surface 26. As a result, the deposition material 98 can be adhered to the organic EL substrate 92 with high dimensional accuracy and positional accuracy.

[0086] Manufacturing method of deposition mask device Next, a method for manufacturing the deposition mask device 10 by combining the deposition mask 20 and the frame 15 will be described. First, the frame 15 is prepared. Then, as shown in FIG. 25, the second surface 20b of the deposition mask 20 is fixed to the frame 15 by welding or the like. For example, first, in a state in which the frame 15 and the deposition mask 20 are overlapped, the deposition mask 20 is photographed from the first surface 20a side using a camera or the like. At this time, tension may be applied to the deposition mask 20. Next, the position of the deposition mask 20 with respect to the frame 15 is detected based on the image obtained by photographing. For example, the position of the outline of the deposition mask 20 in the longitudinal direction D1 is detected. Next, the position of the deposition mask 20 is adjusted so that the position of the deposition mask 20 with respect to the frame 15 is a predetermined position.

[0087] According to the present embodiment, as described above, when the long side surface 26 is viewed from the first surface 20a side, the first portion 261 is not visible. In addition, since the first portion 261 extends to the first surface 20a, that is, since the first end portion 261a of the first portion 261 coincides with the first connection portion 20e, when the long side surface 26 is viewed from the first surface 20a side, the surface of the long side surface 26 other than the first portion 261 is not visible. Therefore, the outline of the deposition mask 20 in the longitudinal direction D1 is clearly defined by the first connection portion 20e between the first surface 20a and the long side surface 26. Therefore, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be easily detected. This allows the position of the outline of the deposition mask 20 in the longitudinal direction D1 to be more accurately adjusted with respect to the frame 15.

[0088] Vapor deposition method Next, a deposition method for depositing the deposition material 98 on a substrate such as an organic EL substrate 92 using the deposition mask 20 will be described. First, the deposition mask device 10 is arranged so that the deposition mask 20 faces the organic EL substrate 92. In addition, the deposition mask 20 is brought into close contact with the organic EL substrate 92 using a magnet 93. In this state, the deposition material 98 is evaporated and caused to fly to the organic EL substrate 92 through the deposition mask 20, so that the deposition material 98 can be attached to the organic EL substrate 92 in a pattern corresponding to the through-holes 25 of the deposition mask 20. Here, in this embodiment, as described above, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be easily detected. Therefore, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be more accurately adjusted with respect to the organic EL substrate 92. This allows the deposition material 98 to be attached to the organic EL substrate 92 with high positional accuracy.

[0089] It should be noted that various modifications can be made to the above-described embodiment. Below, the modified examples will be described with reference to the drawings as necessary. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above-described embodiment will be used for parts that can be configured in the same manner as in the above-described embodiment, and duplicated descriptions will be omitted. Also, if it is clear that the effects obtained in the above-described embodiment can also be obtained in the modified examples, the description may be omitted.

[0090] (Variations of long side) 20 of the above-described embodiment shows an example in which the second recess 35 formed on the second surface 64b of the metal plate 64 reaches the first surface 64a to form the long side surface 26 separated from other portions of the metal plate 64. In this modified example, an example in which the first recess 30 formed on the first surface 64a of the metal plate 64 and the second recess 35 formed on the second surface 64b are communicated to form the long side surface 26 separated from other portions of the metal plate 64 will be described.

[0091] FIG. 26 is a cross-sectional view showing the long side surface 26 of the deposition mask 20 in this modification. The long side surface 26 includes a first portion 261 and a second portion 262 that is connected to a first end portion 261a of the first portion 261 and reaches the first surface 20a. The second portion 262 is a part of the first recess 30 formed by etching the first surface 64a of the metal plate 64 in the first surface etching process, and is recessed inward. According to this modification, by forming the first recess 30 in a portion of the first surface 64a of the metal plate 64 that will become the long side surface 26, even when the metal plate 64 has a large thickness, for example, a thickness of 20 μm or more or 30 μm or more, the long side surface 26 can be formed by etching. Although not shown, the short side surface 27 may also include a second portion formed by the first recess 30 and a first portion formed by the second recess 35.

[0092] When the long side surface 26 or the short side surface 27 includes the second portion on the first surface 64a side, the first-surface etching step is preferably performed so that the dimension in the width direction D2 of the first recess 30 formed in the portion of the first surface 64a of the metal plate 64 that will become the long side surface 26 or the short side surface 27 is smaller than the dimension in the width direction D2 of the first recess 30 formed in the portion of the first surface 64a of the metal plate 64 that will become the through hole 25. This makes it possible to prevent the first recess 30 corresponding to the long side surface 26 or the short side surface 27 from becoming a starting point of folding of the metal plate 64 when the metal plate 64 is transported to a location where the second-surface etching step is performed after the first-surface etching step.

[0093] As shown in FIG. 26, the first end 261a of the first portion 261 is located outside the first connection portion 20e at which the first surface 20a of the deposition mask 20 and the second portion 262 of the long side surface 26 are connected. For this reason, when the deposition mask 20 is viewed from the first surface 20a side, the second portion 262 is visible, but the first portion 261 is not visible. In the second portion 262, light is scattered in various directions. For this reason, in the example shown in FIG. 26, the second portion 262 is visible or appears in an image as a portion that appears black compared to the first surface 20a. Therefore, it is preferable that the width of the second portion 262 visible when viewed from the first surface 20a side is small. This makes it possible to accurately detect the outline of the deposition mask 20 in the longitudinal direction D1 when viewed from the first surface 20a side, that is, the outline of the long side surface 26.

[0094] 26, the symbol δ represents the distance between the first end 261a and the first connection portion 20e in the planar direction of the first surface 20a. The distance δ corresponds to the width of the second portion 262 as viewed from the first surface 20a side. The distance δ is, for example, 3.5 μm or less, and more preferably 1.0 μm or less.

[0095] In FIG. 26, the symbol r3 represents the distance from the first surface 20a to the first end 261a in the normal direction of the deposition mask 20. The distance r3 is, for example, 2 μm or more and 5 μm or less. This reduces the area of ​​the second portion 262 and suppresses light scattering caused by the second portion 262, so that the outline of the deposition mask 20 in the longitudinal direction D1 when viewed from the first surface 20a side of the second portion 262, that is, the outline of the long side surface 26 can be detected more accurately. In addition, preferably, the distance r3 is smaller than the height r1 of the wall surface 31 of the first recess 30 constituting the through hole 25. In other words, the first end 261a of the long side surface 26 is located closer to the first surface 20a than the hole connection portion 41 of the through hole 25.

[0096] (Short side variation) In the above-described embodiment, an example has been shown in which, in the long side 26 of the deposition mask 20, the first connection portion 20e connecting the first surface 20a and the long side 26 and the first end 261a of the first portion 261 coincide with each other, or the distance between them is 3.5 μm or less. This makes it possible to easily detect the contour of the deposition mask 20 extending in the longitudinal direction D1 when viewed from the first surface 20a. This technical idea may be applied to the short side 27 in addition to the long side 26 or instead of the long side 26. That is, although not shown, the connection portion connecting the first surface 20a and the short side 27 and the end of the inwardly recessed surface of the short side 27 on the first surface 20a side may coincide with each other, or the distance between them may be 3.5 μm or less. This makes it possible to easily detect the contour of the deposition mask 20 extending in the width direction D2 when viewed from the first surface 20a, i.e., the contour of the short side 27.

[0097] In the above embodiment, the deposition mask portion 51 is separated from the support portion 56 by breaking the connection portion 54 between the deposition mask portion 51 and the support portion 56 on the short side surface 27 of the intermediate product 50. However, the example of separating the deposition mask portion 51 from the support portion 56 on the short side surface 27 is not particularly limited. For example, the deposition mask portion 51 may be separated from the support portion 56 by cutting the portion of the intermediate product 50 that will become the short side surface 27 using a processing device such as a laser processing device. In this case, the above-mentioned multiple second penetrating portions 55b may not be formed in the portion of the metal plate 64 that will become the short side surface 27. Alternatively, a groove having a depth that does not penetrate the metal plate 64 may be formed on the first surface 64a or the second surface 64b of the portion of the metal plate 64 that will become the short side surface 27. In this case, by irradiating the metal plate 64 with laser light along the groove, it is possible to reduce burrs caused by laser processing and reduce the amount of shavings generated during laser processing.

[0098] (Other forms) Another first embodiment of the present disclosure is a deposition mask having a plurality of through holes formed therein, the deposition mask comprising a first surface and a second surface in which the through holes are formed, a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a longitudinal direction of the deposition mask, and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a width direction of the deposition mask, the long side surfaces include a first end portion located on the first surface side and a second end portion located on the second surface side and located on the inside of the first end portion, and have a first portion recessed inward, the through holes include a first recess formed on the first surface side and a second recess formed on the second surface side and connected to the first recess at a hole connecting portion, and the first end portion of the first portion of the long side surface is located on the first surface side relative to the hole connecting portion. The first end portion may be a first connecting portion that connects the first surface and the long side surface, and may coincide with a first connecting portion located on the same plane as the first surface. Alternatively, the first end may be a first connection portion where the first surface and the long side surface are connected, and may be located outside a first connection portion located on the same plane as the first surface.

[0099] Another second embodiment of the present disclosure is a deposition mask having a plurality of through holes formed therein, the deposition mask comprising: a first surface and a second surface in which the through holes are formed; a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a longitudinal direction of the deposition mask; and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a width direction of the deposition mask, the long side surfaces including a first end portion located on the first surface side and a second end portion located on the second surface side and positioned more inward than the first end portion, and having a first portion recessed inward, the first end portion being a first connection portion that connects the first surface and the long side surfaces and coinciding with a first connection portion located on the same plane as the first surface.

[0100] In a deposition mask according to another embodiment of the present disclosure, a first connection portion connecting the first surface and the long side surface, the distance in the surface direction of the first surface between the first connection portion located on the same plane as the first surface and the first end portion of the first portion of the long side surface may be 3.5 μm or less.

[0101] In the deposition masks according to the first and second embodiments of the present disclosure, the first portion may be located inside an imaginary plane or line passing through the first end and the second end.

[0102] In the deposition masks according to the first and second embodiments of the present disclosure, the deposition mask may have a thickness of 50 μm or less.

[0103] In the deposition masks according to the first and second other embodiments of the present disclosure, the second end may coincide with a second connection portion that connects the second surface and the long side surface and is located on the same plane as the second surface.

[0104] Another third embodiment of the present disclosure is a manufacturing method of a deposition mask in which a plurality of through holes are formed, the manufacturing method of the deposition mask includes: a step of preparing a metal plate including a first surface and a second surface located on an opposite side to the first surface; and a processing step of processing the metal plate to obtain the deposition mask having the first surface and the second surface in which the through holes are formed, a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a longitudinal direction of the deposition mask, and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a width direction of the deposition mask, wherein the long side surfaces include a first end portion located on the first surface side and a second end portion located on the second surface side and positioned more inward than the first end portion, and have a first portion recessed inward, the through holes include a first recess portion formed on the first surface side and a second recess portion formed on the second surface side and connected to the first recess portion at a hole connecting portion, and the first end portion of the first portion of the long side surface is located on the first surface side relative to the hole connecting portion. The processing step may include a second-side etching step of etching the metal plate from the second surface side to form the first portion of the long side surface, and the second-side etching step may be performed so that the first end of the first portion coincides with a first connection portion that connects the first surface and the long side surface and is located on the same plane as the first surface. Alternatively, the processing step may include a second-side etching step of etching the metal plate from the second surface side to form the first portion of the long side surface, and the processing step may further include a first-side etching step of etching the metal plate from the first surface side to form a surface of the long side surface that is located between the first end of the first portion and the first surface of the metal plate.

[0105] Another fourth embodiment of the present disclosure is a manufacturing method of a deposition mask in which a plurality of through holes are formed, the manufacturing method including: a step of preparing a metal plate including a first surface and a second surface located opposite to the first surface; and a processing step of processing the metal plate to obtain the deposition mask having the first surface and the second surface in which the through holes are formed, a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a longitudinal direction of the deposition mask, and a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask in a width direction of the deposition mask. the long side includes a first end located on the first surface side and a second end located on the second surface side and located more inward than the first end, and has a first portion recessed inward, the processing step includes a second surface etching step of etching the metal plate from the second surface side to form the first portion of the long side, and the second surface etching step is performed so that the first end of the first portion coincides with a first connection portion that connects the first surface and the long side and is located on the same plane as the first surface.

[0106] In the method for manufacturing a deposition mask according to the other third and fourth embodiments of the present disclosure, a first connection portion that connects the first surface and the long side surface, wherein the distance in the surface direction of the first surface between the first connection portion located on the same plane as the first surface and the first end portion of the first portion of the long side surface is 3.5 μm or less. EXAMPLES

[0107] Next, the embodiments of the present disclosure will be described more specifically with reference to examples. However, the embodiments of the present disclosure are not limited to the description of the following examples as long as they do not depart from the gist of the disclosure.

[0108] Example 1 First, a metal plate 64 having a thickness of 25 μm was prepared. Next, the above-mentioned processing step was performed to form a plurality of through holes 25, each of which is composed of a first recess 30 and a second recess 35, in the metal plate 64. In addition, a second recess 35 was formed in a portion of the second surface 64b of the metal plate 64 corresponding to the long side surface 26, and the second recess 35 was formed extending to the first surface 64a. FIG. 27 shows an observation result of a cross section of the long side surface 26. In addition, FIG. 28A shows a result of observing the deposition mask 20 having the long side surface 26 shown in FIG. 27 from the first surface 20a side, and FIG. 28B shows a result of observing the deposition mask 20 from the second surface 20b side.

[0109] 28B, when the deposition mask 20 is observed from the second surface 20b side, the first portion 261 is visible. On the other hand, when the deposition mask 20 is observed from the first surface 20a side, the first portion 261 is not visible. For this reason, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be easily detected.

[0110] Example 2 First, a metal plate 64 having a thickness of 30 μm was prepared. Next, the above-mentioned processing step was performed to form a plurality of through holes 25, each composed of a first recess 30 and a second recess 35, in the metal plate 64. In addition, the first recess 30 was formed in a portion of the first surface 64a of the metal plate 64 corresponding to the long side surface 26, and the second recess 35 communicating with the first recess 30 was formed in a portion of the second surface 64b corresponding to the long side surface 26. FIG. 29A shows an observation result of a cross section of the long side surface 26. The long side surface 26 includes a first portion 261 consisting of a portion of the second recess 35 and a second portion 262 consisting of a portion of the first recess 30.

[0111] Fig. 29B is an enlarged cross-sectional view of the second portion 262 of the long side surface 26 of Fig. 29A. The distance δ between the first end portion 261a and the first connection portion 20e was 0.7 µm.

[0112] When the deposition mask 20 having the long side surface 26 shown in FIG. 29A and FIG. 29B is observed from the second surface 20b side, the first portion 261 is visible. On the other hand, when the same deposition mask 20 is observed from the first surface 20a side, the first portion 261 is not visible, and instead the second portion 262 is visible. The distance δ between the first end 261a and the first connection portion 20e is 0.7 μm. Therefore, even when the deposition mask 20 is observed from the first surface 20a side using a camera in a state where the field of view size of the camera in the width direction D2 is expanded to about 3.5 μm, both the first end 261a and the first connection portion 20e can be confirmed. Therefore, the outline of the deposition mask 20 can be easily detected.

[0113] Example 3 A deposition mask 20 was produced in the same manner as in Example 1 described above, except that a metal plate 64 having a thickness of 15 μm was used. FIG. 30 shows the observation result of a cross section of the long side surface 26. As shown in FIG. 27, in this example, as in Example 1, a first portion 261 having a curved surface curved to be concave inward extends from the second surface 20b to the first surface 20a. In this case, since the first end portion 261a of the first portion 261 coincides with the first connection portion 20e, the first portion 261 is not visible when the deposition mask 20 is viewed from the first surface 20a side. Therefore, when the deposition mask 20 is viewed along the normal direction of the first surface 20a, the position of the outline of the deposition mask 20 in the longitudinal direction D1 can be easily detected. [Explanation of symbols]

[0114] 10. Deposition mask device 15 Frames 20 Deposition mask 20a Page 1 20b 2nd side 21 Base material 22 Effective Area 23 Surrounding Area 25 Through hole 26 long side 261 Part 1 262 Part 2 27 short side 30 First recess 31 Wall 35 Second recess 36 Wall 41 hole connection 43 Top Section 50 Intermediate products 51 Deposition mask part 54 Connection points 55 Gap 56 Support part 64 Metal plate 65a First resist pattern 65b Second resist pattern 65c First resist film 65d Second resist film 70 Processing equipment 72 Transport roller 73 Separation device 90 Vapor deposition equipment 92 Organic EL board 98 Evaporation materials

Claims

1. An intermediate product of a deposition mask, a plurality of deposition mask portions in which a plurality of through holes are formed, and a support portion surrounding the deposition mask portions in a plan view and partially connected to the deposition mask portions, The deposition mask portion is a first surface and a second surface in which the through hole is formed; a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a longitudinal direction of the deposition mask portion; a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a width direction of the deposition mask portion; the long side surface includes a first end portion located on the first surface side and a second end portion located on the second surface side and on the inside of the first end portion, and has a first portion recessed inward; the through hole includes a first recess formed on the first surface side and a second recess formed on the second surface side and connected to the first recess at a hole connecting portion, An intermediate product, wherein the first end of the first portion of the long side surface is located on the first surface side relative to the hole connection portion.

2. The intermediate product according to claim 1 , wherein the first end coincides with a first connection portion where the first surface and the long side surface are connected and which is located on the same plane as the first surface.

3. The intermediate product according to claim 1 , wherein the first end is a first connection portion where the first surface and the long side surface are connected, and is located outside a first connection portion located on the same plane as the first surface.

4. An intermediate product of a deposition mask, a plurality of deposition mask portions in which a plurality of through holes are formed, and a support portion surrounding the deposition mask portions in a plan view and partially connected to the deposition mask portions, The deposition mask portion is a first surface and a second surface in which the through hole is formed; a pair of long side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a longitudinal direction of the deposition mask portion; a pair of short side surfaces connected to the first surface and the second surface and defining an outline of the deposition mask portion in a width direction of the deposition mask portion; the long side surface includes a first end portion located on the first surface side and a second end portion located on the second surface side and more inward than the first end portion, and has a first portion recessed inward, and a second portion connected to the first end portion of the first portion and reaching the first surface, An intermediate product, comprising: a first connection portion that connects the first surface and the second portion of the long side surface, wherein the distance in the surface direction of the first surface between the first connection portion located on the same plane as the first surface and the first end portion of the long side surface is 3.5 μm or less.

5. The long side has the first portion and a second portion connected to the first end of the first portion and extending to the first surface, An intermediate product as described in claim 1 or 3, wherein a first connection portion connecting the first surface and the second portion of the long side surface, the distance in the surface direction of the first surface between the first connection portion located on the same plane as the first surface and the first end portion of the long side surface, is 3.5 μm or less.

6. The intermediate product according to claim 1 , wherein the first portion is located inside an imaginary plane or line passing through the first end and the second end.

7. The intermediate product according to claim 1 , wherein the deposition mask portion has a thickness of 50 μm or less.

8. The intermediate product according to any one of claims 1 to 4, wherein the second end is a second connection portion where the second surface and the long side surface are connected, and coincides with a second connection portion located on the same plane as the second surface.

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