Method for manufacturing a metal plate and method for manufacturing an evaporation mask

Abstract

The present invention relates to a method for manufacturing a metal plate and a method for manufacturing an evaporation mask. The metal plate has two or more pits on a surface of the metal plate. The method for manufacturing a metal plate for manufacturing an evaporation mask includes an inspection step of determining the quality of the metal plate based on the sum of the volumes of the two or more pits on a portion of the surface of the metal plate.

Description

[0001] This application is a divisional application. The original application, Chinese National Application No. 201811344277.0, was filed on November 13, 2018, and is entitled "Metal plate for manufacturing a vapor deposition mask, a method for manufacturing the metal plate, and a vapor deposition mask." The corresponding divisional application, Chinese National Application No. 202111239868.3, was filed on November 13, 2018, and is also entitled "Metal plate for manufacturing a vapor deposition mask, a method for manufacturing the metal plate, and a vapor deposition mask." Technical Field

[0002] Embodiments of this application relate to a metal plate for manufacturing a vapor deposition mask and a method for manufacturing the metal plate. Additionally, embodiments of this application relate to a vapor deposition mask and a method for manufacturing the vapor deposition mask. Background Technology

[0003] In recent years, display devices used in portable devices such as smartphones and tablets have been required to have high resolution, for example, a pixel density of 500 ppi or higher. Furthermore, the demand for ultra-high definition (UHD) in portable devices is also constantly increasing; in this case, a pixel density of 800 ppi or higher is preferred for the display device.

[0004] In display devices, organic EL (Organic Electron) displays have attracted much attention due to their good responsiveness, low power consumption, and high contrast. A known method for forming pixels in an organic EL display device involves using a vapor deposition mask with through-holes arranged in a desired pattern to form pixels. Specifically, the vapor deposition mask is first bonded to a substrate for the organic EL display device, and then the bonded vapor deposition mask and substrate are placed together into a vapor deposition apparatus to perform a vapor deposition process on the substrate to deposit organic material. This allows pixels containing organic material to be formed on the substrate in a pattern corresponding to the pattern of the through-holes in the vapor deposition mask.

[0005] As a method for manufacturing vapor deposition masks, a method for forming through-holes in a metal plate by etching using photolithography is known. For example, a first resist pattern is first formed on a first surface of the metal plate by exposure and development, and a second resist pattern is formed on a second surface of the metal plate by exposure and development. Next, the area on the first surface of the metal plate not covered by the first resist pattern is etched to form a first recess on the first surface of the metal plate. Then, the area on the second surface of the metal plate not covered by the second resist pattern is etched to form a second recess on the second surface of the metal plate. At this time, etching is performed such that the first recess and the second recess communicate, thereby forming a through-hole penetrating the metal plate. The metal plate used to manufacture the vapor deposition mask is, for example, manufactured by rolling a base material made of a nickel-containing iron alloy.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent No. 5382259 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] The purpose of this application is to provide a metal plate suitable for manufacturing vapor deposition masks.

[0011] Methods for solving problems

[0012] One embodiment of this application is a method for manufacturing a metal plate, which is a method for manufacturing a metal plate for manufacturing a vapor deposition mask. The metal plate has two or more pits located on the surface of the metal plate. The manufacturing method includes the following inspection step: determining the quality of the metal plate based on the sum of the volumes of the two or more pits located on a portion of the surface.

[0013] In one embodiment of the metal plate manufacturing method of this application, the inspection step may include the following steps: a calculation step, which divides the sum of the volumes of portions of two or more of the aforementioned pits that are at or above a correction distance from the surface in the thickness direction of the metal plate by the area of ​​the aforementioned portion of the surface, thereby calculating a pit correction volume density; and a determination step, which determines that the metal plate is good if the pit correction volume density is below a first threshold. In this case, the determination step can determine that the metal plate is good if the pit correction volume density is above a second threshold but below the first threshold.

[0014] In one embodiment of the metal plate manufacturing method of this application, the inspection step may include the following steps: a calculation step, dividing the sum of the volumes of portions of two or more of the aforementioned pits that are at or above a correction distance from the surface in the thickness direction of the metal plate by the area of ​​the aforementioned portion of the surface, thereby calculating the pit correction volume density; and a screening step, screening out the aforementioned metal plates whose pit correction volume density is below a first threshold. In this case, the screening step can screen out the aforementioned metal plates whose pit correction volume density is above a second threshold but below a first threshold.

[0015] In one embodiment of the metal plate manufacturing method of this application, the above-mentioned correction distance can be 0.2 μm.

[0016] In one embodiment of the metal plate manufacturing method of this application, the aforementioned first threshold can be 15000 μm. 3 / mm 2 Additionally, the aforementioned second threshold can be 10 μm. 3 / mm 2 .

[0017] In one embodiment of the metal plate manufacturing method of this application, the above calculation process may include the following measurement process: measuring the depth of the pit at each position of the above portion of the above surface.

[0018] In one embodiment of the metal plate manufacturing method of this application, the depth of the aforementioned pit can be measured using a laser microscope.

[0019] In one embodiment of the metal plate manufacturing method of this application, the area of ​​the aforementioned portion of the surface can be 0.1 mm. 2 above.

[0020] One embodiment of this application is a metal plate used for manufacturing a vapor deposition mask. The metal plate has two or more pits located on its surface. When the sum of the volumes of the portions of the two or more pits located on a portion of the surface that are at least 0.2 μm away from the surface in the thickness direction of the metal plate is defined as the pit correction volume, the pit correction volume density calculated by dividing the pit correction volume by the area of ​​the aforementioned portion of the surface is 15000 μm³. 3 / mm 2 The aforementioned pit correction volume is calculated based on the results obtained by measuring the depth of the pits at various locations on the aforementioned portion of the surface using a laser microscope, where the area of ​​the aforementioned portion of the surface is 0.1 mm. 2 above.

[0021] In one embodiment of the metal plate of this application, the volumetric density of the aforementioned pit correction can be 10 μm. 3 / mm 2 above.

[0022] In one embodiment of this application, the metal plate may be made of a nickel-containing iron alloy.

[0023] One embodiment of this application is a method for manufacturing a vapor deposition mask, which is a method for manufacturing a vapor deposition mask having two or more through holes. The manufacturing method includes the following steps: preparing a metal plate manufactured using the metal plate manufacturing method described above, or a metal plate described above; and a processing step of etching the metal plate to form the through holes in the metal plate.

[0024] One embodiment of this application is a vapor deposition mask comprising: a metal plate having two or more recesses on its surface; and two or more through holes formed in the metal plate. When the sum of the volumes of the portions of the two or more recesses located on a portion of the surface that are at least 0.2 μm away from the surface in the thickness direction of the metal plate is referred to as the recess correction volume, the recess correction volume density calculated by dividing the recess correction volume by the area of ​​the portion of the surface is 15000 μm. 3 / mm 2 The aforementioned pit correction volume is calculated based on the results obtained by measuring the depth of the pits at various locations on the aforementioned portion of the surface using a laser microscope, where the area of ​​the aforementioned portion of the surface is 0.1 mm. 2 above.

[0025] In one embodiment of the vapor deposition mask of this application, the volumetric density of the aforementioned pit correction can be 10 μm. 3 / mm 2 above.

[0026] The effects of the invention

[0027] According to one embodiment of this application, a metal plate suitable for manufacturing vapor deposition masks can be obtained efficiently. Attached Figure Description

[0028] Figure 1 This is a diagram showing a vapor deposition apparatus having a vapor deposition mask apparatus according to one embodiment of this application.

[0029] Figure 2 It shows the use Figure 1 A cross-sectional view of an organic EL display device (organic EL display device intermediate) manufactured by the vapor deposition mask apparatus shown.

[0030] Figure 3 This is a top view showing a vapor deposition mask apparatus according to one embodiment of this application.

[0031] Figure 4 It is shown Figure 3 A partial top view of the effective area of ​​the vapor deposition mask shown.

[0032] Figure 5 It is along Figure 4 A cross-sectional view of the VV line.

[0033] Figure 6 It is along Figure 4 A cross-sectional view of the VI-VI line.

[0034] Figure 7 It is along Figure 4 A cross-sectional view of line VII-VII.

[0035] Figure 8 This is a partial top view showing a modified example of the effective area of ​​a vapor deposition mask.

[0036] Figure 9 It is along Figure 8 A cross-sectional view of the IX-IX line.

[0037] Figure 10 It is a cross-sectional view showing the through hole and the surrounding area magnified.

[0038] Figure 11 This diagram illustrates the process of rolling a base material to obtain a metal sheet with a desired thickness.

[0039] Figure 12 This diagram illustrates the process of annealing a metal sheet obtained from rolling.

[0040] Figure 13 This diagram illustrates a case where there are more than two pits on the surface of a metal sheet obtained through rolling.

[0041] Figure 14 This is a diagram showing an example of a cross-section of a metal plate.

[0042] Figure 15 It shows the side view from the first face. Figure 14 The diagram shows a cross-sectional view of the process of etching a metal plate to form a second recess.

[0043] Figure 16 This is a cross-sectional view showing the process of forming a second recess that communicates with the first recess on the second side of a metal plate.

[0044] Figure 17 This diagram illustrates how the accuracy of the opening size of a through hole is reduced due to pits in the metal plate.

[0045] Figure 18 This is a top view used to illustrate the inspection process for metal plates.

[0046] Figure 19 This is a cross-sectional diagram used to illustrate the inspection process of metal plates.

[0047] Figure 20 This is a schematic diagram illustrating an example of a method for manufacturing a vapor deposition mask.

[0048] Figure 21 This diagram illustrates the process of forming a resist film on a metal plate.

[0049] Figure 22 This diagram illustrates the process of ensuring a tight seal between the exposure mask and the resist film.

[0050] Figure 23 This is a diagram illustrating the process of developing a resist film.

[0051] Figure 24 This is a diagram showing the etching process on the first side.

[0052] Figure 25 This is a diagram illustrating the process of coating the first recess with resin.

[0053] Figure 26 This diagram illustrates the etching process on the second side.

[0054] Figure 27 It is shown Figure 26 A diagram of the subsequent second-side etching process.

[0055] Figure 28 This diagram illustrates the process of removing resin and resist patterns from a metal plate.

[0056] Figure 29 This is a table showing the results of inspecting the surface pits of each sample using the first inspection example.

[0057] Figure 30 This is a top view showing an example of the patterns formed in the recesses and ribs of the various metal plates.

[0058] Figure 31 yes Figure 30 The cross-sectional view of the metal plate shown.

[0059] Figure 32 This is a top view showing another example of the patterns formed in the recesses and ribs of the various metal plates.

[0060] Figure 33 This is a scatter plot showing the correlation between the indicators obtained through the first inspection example and the dimensional accuracy of the ribs formed in each sample.

[0061] Figure 34 This is a table showing the results of inspecting the surface pits of each metal plate sample through inspection examples two through five.

[0062] Figure 35 This is a scatter plot showing the correlation between the indicators obtained through the second inspection example and the dimensional accuracy of the ribs formed in each sample.

[0063] Figure 36 This is a scatter plot showing the correlation between the indicators obtained through the third inspection example and the dimensional accuracy of the ribs formed in each sample.

[0064] Figure 37 This is a scatter plot showing the correlation between the indicators obtained through the fourth inspection example and the dimensional accuracy of the ribs formed in each sample.

[0065] Figure 38 This is a scatter plot showing the correlation between the indicators obtained through the fifth inspection example and the dimensional accuracy of the ribs formed in each sample.

[0066] Figure 39 This is a diagram illustrating an example of the distribution of the pit-corrected volumetric density of two or more selected metal plates.

[0067] Figure 40 This is a diagram illustrating an example of the distribution of the pit-corrected volumetric density of two or more selected metal plates.

[0068] Figure 41 This is a diagram illustrating an example of the distribution of the pit-corrected volumetric density of two or more manufactured metal plates.

[0069] Symbol Explanation

[0070] 10 Evaporation mask device

[0071] 15 Framework

[0072] 20 Evaporation Mask

[0073] 21 Metal Plate

[0074] 22 Effective Area

[0075] 23 Surrounding Area

[0076] 25 Through Holes

[0077] 30 First recess

[0078] 31 wall

[0079] 35 Second recess

[0080] 36 wall

[0081] 41 Connecting part

[0082] 41a Notch

[0083] 43 Top

[0084] 50 Intermediate products

[0085] 64 long strip metal plates

[0086] 64c dent

[0087] 65a First Anti-corrosion Pattern

[0088] 65b Second Anti-corrosion Pattern

[0089] 65c First resist film

[0090] 65d Second Anti-corrosion Film

[0091] 711 Inspection Area

[0092] 712 unit area

[0093] 713 pixels

[0094] 72 Processing equipment

[0095] 73 Separation device

[0096] 80 samples

[0097] 81 recess

[0098] 82 Ribs

[0099] 90 Evaporation Deposition Unit

[0100] 92 Organic EL substrate

[0101] 98 Evaporation materials Detailed Implementation

[0102] Hereinafter, one embodiment of the present application will be described with reference to the accompanying drawings. It should be noted that, in the drawings accompanying this application specification, the proportions and aspect ratios have been appropriately altered based on the actual object for ease of illustration and understanding.

[0103] It should be noted that the embodiments of this application can be combined with other embodiments or modifications within a scope that does not produce contradictions. Furthermore, other embodiments, as well as other embodiments and modifications, can also be combined with each other within a scope that does not produce contradictions. Additionally, modifications can also be combined with each other within a scope that does not produce contradictions.

[0104] Furthermore, in the embodiments of this application, when two or more steps are disclosed regarding the manufacturing method or other methods, other undisclosed steps may be performed between the disclosed steps. Additionally, the order of the disclosed steps is arbitrary as long as it does not create contradictions.

[0105] Furthermore, the problems to be solved by the embodiments of this application will be explained.

[0106] Sometimes, pits such as oil pits are formed on the surface of rolled metal sheets. The condition of these pits affects the dimensional and positional accuracy of through holes formed in the metal sheet. For example, if the depth of the pits increases, the size of the through holes formed in the metal sheet will be larger than the design value. Therefore, techniques for inspecting the condition of pits on the surface of metal sheets are important.

[0107] As a technique for inspecting the surface undulations such as pits on a metal sheet, it is known to calculate the arithmetic mean surface roughness Ra and the maximum profile height Ry. The arithmetic mean roughness Ra is a value obtained by measuring the position (hereinafter also referred to as height position) of the metal sheet surface in the thickness direction at two or more points on a defined straight line, and calculating its average value. The maximum profile height Ry is the difference between the maximum and minimum values ​​of the measured height positions of the metal sheet surface at two or more points on a defined straight line.

[0108] The inventors conducted in-depth research and found that the correlation between surface undulation indicators such as arithmetic mean roughness Ra in existing technologies and the dimensional accuracy of through holes formed in metal sheets is not necessarily high. Therefore, assuming that the quality of metal sheets is judged based on arithmetic mean roughness Ra, a more stringent threshold for determining whether a sheet is acceptable is needed to prevent erroneous judgments. As a result, the yield of metal sheets decreases.

[0109] The purpose of this application is to provide a metal plate and a method for manufacturing the metal plate that can effectively solve this problem, as well as a vapor deposition mask and a method for manufacturing the vapor deposition mask.

[0110] Figures 1 to 28 This is a diagram illustrating one embodiment of this application. In the following embodiments and variations, a method for manufacturing a vapor deposition mask is used as an example: this method is used to pattern organic materials onto a substrate in a desired pattern during the manufacture of an organic EL display device. However, the application is not limited to this; the embodiments of this application can be applied to vapor deposition masks used in various applications.

[0111] It should be noted that the terms "plate," "sheet," and "membrane" used in this specification are not distinguished from each other solely based on their different names. For example, "plate" also includes components that can be called sheets or membranes.

[0112] Furthermore, "sheet surface (film surface)" refers to the surface of a sheet-like (sheet-like, film-like) component that is aligned with the planar direction when viewed as a whole and in a general manner. Additionally, the normal direction used for sheet-like (sheet-like, film-like) components refers to the normal direction relative to the sheet surface (sheet-like, film-like) surface of that component.

[0113] Furthermore, the specific terms used in this specification regarding the conditions and physical properties of shape or geometry, and their degree, such as "parallel," "perpendicular," "same," "equal," etc., as well as the values ​​of length, angle, and physical properties, are not limited to strict definitions, but are interpreted to include a range of degrees to which the same function can be expected.

[0114] First, refer to Figure 1 The vapor deposition apparatus 90 for performing the vapor deposition process of depositing vapor-deposited material onto an object will be described. For example... Figure 1 As shown, the vapor deposition apparatus 90 may include a vapor deposition source (e.g., a crucible 94), a heater 96, and a vapor deposition mask apparatus 10. Additionally, the vapor deposition apparatus 90 may include an exhaust unit to create a vacuum atmosphere inside the apparatus. The crucible 94 contains vapor deposition materials 98, such as organic light-emitting materials. The heater 96 heats the crucible 94 to evaporate the vapor deposition material 98 under a vacuum atmosphere. The vapor deposition mask apparatus 10 is positioned opposite the crucible 94.

[0115] The vapor deposition mask apparatus 10 will be described below. For example... Figure 1 As shown, the vapor deposition mask apparatus 10 may include a vapor deposition mask 20 and a frame 15 supporting the vapor deposition mask 20. The frame 15 supports the vapor deposition mask 20 in a stretched state along its surface direction to prevent the vapor deposition mask 20 from bending. Figure 1 As shown, the vapor deposition mask apparatus 10 is arranged within the vapor deposition apparatus 90 with the vapor deposition mask 20 and the substrate (e.g., an organic EL substrate) 92, which is the object to which the vapor deposition material 98 is attached, facing each other. In the following description, the surface of the vapor deposition mask 20 on the side of the organic EL substrate 92 is referred to as the first surface 20a, and the surface located on the opposite side of the first surface 20a is referred to as the second surface 20b.

[0116] like Figure 1As shown, the vapor deposition mask apparatus 10 may include a magnet 93, which is disposed on the surface of the organic EL substrate 92 opposite to the vapor deposition mask 20. By providing the magnet 93, the vapor deposition mask 20 can be attracted to the magnet 93 by magnetic force, thereby making the vapor deposition mask 20 and the organic EL substrate 92 fit tightly together.

[0117] Figure 3 This is a top view of the vapor deposition mask assembly 10 viewed from the first surface 20a of the vapor deposition mask 20. (See image below.) Figure 3 As shown, the vapor deposition mask assembly 10 may include two or more vapor deposition masks 20. Each vapor deposition mask 20 may include a pair of long sides 26 and a pair of short sides 27. For example, each vapor deposition mask 20 may have a rectangular shape. Each vapor deposition mask 20 may be fixed to the frame 15, for example, by spot welding, in the portion of the pair of short sides 27 or nearby.

[0118] The vapor deposition mask 20 may comprise a plate-shaped metal substrate having two or more through holes 25 extending through it. Vapor deposition material 98, evaporated from the crucible 94 and arriving at the vapor deposition mask apparatus 10, adheres to the organic EL substrate 92 through the through holes 25 of the vapor deposition mask 20. Thus, the vapor deposition material 98 can be deposited on the surface of the organic EL substrate 92 in a desired pattern corresponding to the positions of the through holes 25 of the vapor deposition mask 20.

[0119] Figure 2 It shows the use Figure 1 This is a cross-sectional view of an organic EL display device 100 manufactured by a vapor deposition apparatus 90. The organic EL display device 100 includes at least an organic EL substrate 92 and pixels containing vapor deposition material 98 arranged in a pattern. It should be noted that, although not shown, the organic EL display device 100 further includes electrodes electrically connected to the pixels containing the vapor deposition material 98. These electrodes are, for example, pre-positioned on the organic EL substrate 92 before the vapor deposition material 98 is attached to the organic EL substrate 92 in the vapor deposition process. Furthermore, the organic EL display device 100 may also include other components such as sealing members that seal the space surrounding the pixels containing the vapor deposition material 98 from the outside. Therefore, Figure 2 The organic EL display device 100 can also be referred to as an organic EL display device intermediate generated in the intermediate stage of manufacturing the organic EL display device.

[0120] It should be noted that, when it is desired to perform a color display based on multiple colors, a vapor deposition apparatus 90 equipped with a vapor deposition mask 20 corresponding to each color is prepared, and the organic EL substrate 92 is sequentially placed into each vapor deposition apparatus 90. This allows, for example, organic light-emitting materials for red, green, and blue to be sequentially vapor-deposited onto the organic EL substrate 92.

[0121] Furthermore, vapor deposition is sometimes performed inside a vapor deposition apparatus 90 under a high-temperature atmosphere. In this case, during the vapor deposition process, the vapor deposition mask 20, frame 15, and organic EL substrate 92, which are held inside the vapor deposition apparatus 90, are also heated. At this time, the vapor deposition mask 20, frame 15, and organic EL substrate 92 exhibit dimensional changes based on their respective coefficients of thermal expansion. In this case, when there is a large difference in the coefficients of thermal expansion of the vapor deposition mask 20, frame 15, and organic EL substrate 92, positional shifts occur due to these differences in dimensional changes. As a result, the dimensional accuracy and positional accuracy of the vapor deposition material attached to the organic EL substrate 92 are reduced.

[0122] To address this issue, it is preferable that the coefficients of thermal expansion of the vapor deposition mask 20 and the frame 15 are equal to those of the organic EL substrate 92. For example, when using a glass substrate as the organic EL substrate 92, a nickel-containing iron alloy can be used as the main material for the vapor 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 constituting the substrate of the vapor deposition mask 20. Specific examples of nickel-containing iron alloys include: Invar alloy materials containing 34% by mass or more and 38% by mass or less of nickel; super Invar alloy materials containing cobalt in addition to 30% by mass or more and 34% by mass or less of nickel; low thermal expansion Fe-Ni based plating alloys containing 38% by mass or more and 54% by mass or less of nickel; and so on.

[0123] It should be noted that, during the vapor deposition process, if the temperatures of the vapor deposition mask 20, frame 15, and organic EL substrate 92 do not reach high temperatures, there is no particular need to ensure that the coefficients of thermal expansion of the vapor deposition mask 20 and frame 15 are equal to those of the organic EL substrate 92. In this case, materials other than the aforementioned iron alloys can be used as the materials constituting the vapor deposition mask 20. For example, chromium-containing iron alloys or other iron alloys other than the aforementioned nickel-containing iron alloys can be used. As a chromium-containing iron alloy, for example, an iron alloy known as stainless steel can be used. Alternatively, alloys other than iron alloys such as nickel or nickel-cobalt alloys can also be used.

[0124] Next, the vapor deposition mask 20 will be described in detail. For example... Figure 3 As shown, the vapor deposition mask 20 may include: a pair of edge portions (first edge portion 17a and second edge portion 17b) including a pair of short sides 27 of the vapor deposition mask 20; and a middle portion 18 located between the pair of edge portions 17a and 17b.

[0125] First, the edge portions 17a and 17b will be described in detail. Edge portions 17a and 17b are portions of the vapor deposition mask 20 fixed to the frame 15. In this embodiment, the edge portions 17a and 17b are integrally formed with the middle portion 18. It should be noted that the edge portions 17a and 17b may also be formed from components different from the middle portion 18. In this case, the edge portions 17a and 17b are joined to the middle portion 18, for example, by welding.

[0126] Next, the intermediate portion 18 will be described. The intermediate portion 18 may include: at least one effective region 22 having a through hole 25 formed from the first surface 20a to the second surface 20b; and a surrounding region 23 surrounding the effective region 22. The effective region 22 is the region in the vapor deposition mask 20 that faces the display area of ​​the organic EL substrate 92.

[0127] exist Figure 3 In the example shown, the central portion 18 includes a plurality of effective regions 22 arranged at predetermined intervals along the long side 26 of the vapor deposition mask 20. Each effective region 22 corresponds to a display area of ​​an organic EL display device 100. Therefore, according to... Figure 1 The vapor deposition mask apparatus 10 shown is capable of performing segment-by-segment repeated vapor deposition (multi-sided deposition) of the organic EL display device 100. It should be noted that one effective area 22 may sometimes correspond to more than two display areas.

[0128] like Figure 3 As shown, the effective area 22 has an approximately quadrilateral shape when viewed from above, or more precisely, an approximately rectangular outline when viewed from above. It should be noted that, although not shown, each effective area 22 can have various shapes depending on the shape of the display area of ​​the organic EL substrate 92. For example, each effective area 22 can also have a circular outline. Furthermore, each effective area 22 can also have an outline similar to that of a display device such as a smartphone.

[0129] The effective region 22 will be described in detail below. Figure 4 This is a top view showing the effective area 22 magnified from the second surface 20b side of the vapor deposition mask 20. (See image) Figure 4 As shown in the illustrated example, two or more through holes 25 formed in each effective region 22 can be arranged at a predetermined interval along two mutually perpendicular directions within that effective region 22. For an example of the through holes 25, please refer to... Figures 5-7 Further details. Figures 5-7 They are Figure 4 A cross-sectional view of the effective region 22 along the VV direction to the VII-VII direction.

[0130] like Figures 5-7As shown, two or more through holes 25 extend from a first surface 20a, which is on one side of the vapor deposition mask 20 along the normal direction N, to a second surface 20b, which is on the other side of the vapor deposition mask 20 along the normal direction N. In the illustrated example, as detailed below, a first recess 30 is formed by etching on the first surface 21a of the metal plate 21, which is on one side of the vapor deposition mask 20 along the normal direction N, and a second recess 35 is formed on the second surface 21b of the metal plate 21, which is on the other side of the vapor deposition mask 20 along the normal direction N. The first recess 30 is connected to the second recess 35, thereby forming a mutual communication between the second recess 35 and the first recess 30. The through hole 25 is composed of the second recess 35 and the first recess 30 connected to the second recess 35.

[0131] like Figures 5-7 As shown, from the second surface 20b side to the first surface 20a side of the vapor deposition mask 20, the opening area of ​​each second recess 35 in the cross-section along the plate surface of the vapor deposition mask 20 at each position along the normal direction N of the vapor deposition mask 20 gradually decreases. Similarly, the opening area of ​​each first recess 30 in the cross-section along the plate surface of the vapor deposition mask 20 at each position along the normal direction N of the vapor deposition mask 20 gradually decreases from the first surface 20a side to the second surface 20b side of the vapor deposition mask 20.

[0132] like Figures 5-7 As shown, the wall surface 31 of the first recess 30 and the wall surface 36 of the second recess 35 are connected by a circumferential connecting portion 41. The connecting portion 41 is drawn by the ridge line of the following protrusion, which is formed by the confluence of the wall surface 31 of the first recess 30, which is inclined relative to the normal direction N of the vapor deposition mask 20, and the wall surface 36 of the second recess 35, which is also inclined relative to the normal direction N of the vapor deposition mask 20. Furthermore, the connecting portion 41 is drawn as a through portion 42 with the opening area of ​​the through hole 25 minimized when the vapor deposition mask 20 is viewed from above.

[0133] like Figures 5-7 As shown, on the surface of the vapor deposition mask 20 on the other side of the normal direction N, i.e., the first surface 20a of the vapor deposition mask 20, two adjacent through holes 25 are spaced apart from each other along the surface of the vapor deposition mask 20. That is, when the first recess 30 is formed by etching the metal plate 21 from the first surface 21a side corresponding to the first surface 20a of the vapor deposition mask 20, as described in the manufacturing method later, the first surface 21a of the metal plate 21 remains between two adjacent first recesses 30.

[0134] Similarly, as Figures 5-7As shown, on one side along the normal direction N of the vapor deposition mask 20, i.e., on the second surface 20b side of the vapor deposition mask 20, two adjacent second recesses 35 are also spaced apart from each other along the plate surface of the vapor deposition mask 20. That is, the second surface 21b of the metal plate 21 remains between two adjacent second recesses 35. In the following description, the portion of the second surface 21b of the metal plate 21 that is not etched and remains is also referred to as the top 43. By manufacturing the vapor deposition mask 20 with such a remaining top 43, the vapor deposition mask 20 can have sufficient strength. As a result, it is possible to suppress, for example, breakage of the vapor deposition mask 20 during transport. It should be noted that if the width β of the top 43 is too large, shadows will be generated during the vapor deposition process, thereby sometimes reducing the utilization efficiency of the vapor deposition material 98. Therefore, it is preferable to manufacture the vapor deposition mask 20 in a way that the width β of the top 43 is not too large. For example, the width β of the top 43 is preferably 2 μm or less. It should be noted that the width β of the top 43 typically varies depending on the direction in which the vapor deposition mask 20 is cut. For example, Figures 5-7 The width β of the top 43 shown may vary. In this case, the evaporation mask 20 can be constructed such that the width β of the top 43 is less than 2 μm, regardless of whether the evaporation mask 20 is cut in any direction. The so-called shadow is the phenomenon that the adhesion of the evaporation material to the area overlapping the through-hole of the evaporation mask 20 in the evaporation object such as the organic EL substrate 92 is hindered by the second surface 20b or wall surface of the evaporation mask 20.

[0135] like Figure 1 As shown, when the vapor deposition mask device 10 is housed in the vapor deposition apparatus 90, such as Figure 5 As shown by the double-dotted line, the first surface 20a of the vapor deposition mask 20 faces the organic EL substrate 92, and the second surface 20b of the vapor deposition mask 20 is located on the side of the crucible 94 holding the vapor deposition material 98. Therefore, the vapor deposition material 98 adheres to the organic EL substrate 92 through the second recess 35, whose opening area gradually decreases. Figure 5As indicated by the arrow pointing from the second surface 20b towards the first surface 20a, the vapor-deposited material 98 moves not only from the crucible 94 towards the organic EL substrate 92 along the normal direction N of the organic EL substrate 92, but also moves in a direction that is significantly inclined relative to the normal direction N of the organic EL substrate 92. In this case, if the thickness of the vapor-deposited mask 20 is large, the obliquely moving vapor-deposited material 98 is prone to getting stuck on the top 43, the wall surface 36 of the second recess 35, or the wall surface 31 of the first recess 30. As a result, the proportion of vapor-deposited material 98 that cannot pass through the through-hole 25 increases. Therefore, in order to improve the utilization efficiency of the vapor-deposited material 98, it is preferable to reduce the thickness t of the vapor-deposited mask 20, thereby reducing the height of the wall surface 36 of the second recess 35 or the wall surface 31 of the first recess 30. That is, as for the metal plate 21 used to constitute the vapor-deposited mask 20, it is preferable to use a metal plate 21 with the smallest possible thickness t, within the range that ensures the strength of the vapor-deposited mask 20. Considering this, in this embodiment, the thickness t of the vapor deposition mask 20 is, for example, 30 μm or less, preferably 25 μm or less, and more preferably 20 μm or less. The thickness t of the vapor deposition mask 20 can be 18 μm or less, or 15 μm or less. On the other hand, if the thickness of the vapor deposition mask 20 is too small, the strength of the vapor deposition mask 20 decreases, and the vapor deposition mask 20 is prone to damage or deformation. Considering this, the thickness t of the vapor deposition mask 20 can be 5 μm or more, 7 μm or more, 10 μm or more, 13 μm or more, or 15 μm or more. It should be noted that the thickness t is the thickness of the surrounding region 23, that is, the thickness of the portion of the vapor deposition mask 20 where the first recess 30 and the second recess 35 are not formed. Therefore, the thickness t can also be said to be the thickness of the metal plate 21.

[0136] The thickness t of the vapor deposition mask 20 can be determined by a combination of any one of the candidate values ​​for the upper limits and any one of the candidate values ​​for the lower limits. For example, the thickness t of the vapor deposition mask 20 can be 5 μm or more but less than 30 μm, 7 μm or more but less than 25 μm, 10 μm or more but less than 20 μm, or 13 μm or more but less than 18 μm. Furthermore, the thickness t of the vapor deposition mask 20 can be determined by a combination of any two of the candidate values ​​for the upper limits. For example, the thickness t of the vapor deposition mask 20 can be 25 μm or more but less than 300 μm. Additionally, the thickness t of the vapor deposition mask 20 can be determined by a combination of any two of the candidate values ​​for the lower limits. For example, the thickness t of the vapor deposition mask 20 can be 5 μm or more but less than 7 μm.

[0137] exist Figure 5In this context, the minimum angle formed by the straight line L1 relative to the normal direction N of the vapor deposition mask 20 is represented by the symbol θ1. The straight line L1 passes through any other position between the connecting portion 41 of the through hole 25 (which has the smallest opening area) and the wall surface 36 of the second recess 35. Increasing the angle θ1 is advantageous in order to ensure that the obliquely moving vapor deposition material 98 reaches the organic EL substrate 92 as much as possible without reaching the wall surface 36. In increasing the angle θ1, in addition to reducing the thickness t of the vapor deposition mask 20, reducing the width β of the aforementioned top 43 is also effective.

[0138] exist Figure 7 In this text, the symbol α represents the width of the unetched portion (hereinafter also referred to as the rib) remaining in the effective area 22 of the first surface 21a of the metal plate 21. The width α of the rib and the dimension r2 of the through portion 42 are appropriately determined according to the size of the organic EL display device and the number of display pixels. For example, the width α of the rib 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.

[0139] The width α of the rib can be 10 μm or more, 15 μm or more, or 20 μm or more. Alternatively, the width α of the rib can be less than 35 μm, less than 30 μm, or less than 25 μm. The range of the rib width α can be determined by a combination of any one of the candidate values ​​for the upper limits and any one of the candidate values ​​for the lower limits. For example, the rib width α can be 10 μm or more but less than 35 μm, 15 μm or more but less than 30 μm, or 20 μm or more but less than 25 μm. Furthermore, the range of the rib width α can be determined by a combination of any two of the candidate values ​​for the upper limits. For example, the rib width α can be 35 μm or more but less than 40 μm. Additionally, the range of the rib width α can be determined by a combination of any two of the candidate values ​​for the lower limits. For example, the rib width α can be 5 μm or more but less than 10 μm.

[0140] The dimension r2 of the through portion 42 can be 15 μm or more, 20 μm or more, 25 μm or more, or 30 μm or more. Furthermore, the lower limit of the dimension r2 of the through portion 42 can also be less than 10 μm. For example, the dimension r of the through portion 42 can be 5 μm or more. Additionally, the dimension r2 of the through portion 42 can be 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, or 35 μm or less. The range of the dimension r2 of the through portion 42 can be determined by a combination of any one of the candidate values ​​for the upper limits and any one of the candidate values ​​for the lower limits. For example, the dimension r2 of the through portion 42 can be 15 μm or more and 55 μm or less, 20 μm or more and 50 μm or less, 25 μm or more and 45 μm or less, 30 μm or more and 40 μm or less, or 30 μm or more and 35 μm or less. Furthermore, the range of the dimension r2 of the through portion 42 can be determined by a combination of any two of the aforementioned candidate values ​​for the multiple upper limits. For example, the dimension r2 of the through portion 42 can be 55 μm or more and 60 μm or less. Additionally, the range of the dimension r2 of the through portion 42 can be determined by a combination of any two of the aforementioned candidate values ​​for the multiple lower limits. For example, the dimension r2 of the through portion 42 can be 5 μm or more and 10 μm or less.

[0141] It should be noted that, in Figures 4-7 The image shows an example where the second surface 21b of a metal plate 21 remains between two adjacent second recesses 35, but it is not limited to this. Figure 8 As shown, depending on the location, etching can also be performed in such a way that two adjacent second recesses 35 are connected. That is, there may also be a location between two adjacent second recesses 35 where no metal plate 21 remains on the second surface 21b. In addition, although not shown, etching can also be performed in such a way that two adjacent second recesses 35 are connected over the entire area of ​​the second surface 21b. Figure 9 yes Figure 8 A cross-sectional view of the effective region 22 along the IX-IX direction.

[0142] Although not limited, the vapor deposition mask 20 of this embodiment is particularly effective when fabricating organic EL display devices with a pixel density of 450 ppi or higher. Hereinafter, refer to... Figure 10 An example of the size of the vapor deposition mask 20 required to fabricate such a high pixel density organic EL display device will be described. Figure 10 It is Figure 5 The enlarged cross-sectional view of the through hole 25 and the area around the vapor deposition mask 20 shown is shown.

[0143] exist Figure 10In this context, as a parameter related to the shape of the through hole 25, the symbol r1 represents the distance from the first surface 20a of the vapor deposition mask 20 to the connecting portion 41 in the direction along the normal direction N of the vapor deposition mask 20, i.e., the height of the wall surface 31 of the first recess 30. Furthermore, the symbol r2 represents the size of the portion of the first recess 30 that connects to the second recess 35, i.e., the size of the through portion 42. Additionally, in... Figure 10 In the figure, the symbol θ2 represents the angle between the straight line L2 and the normal direction N of the metal plate 21. The straight line L2 is formed by connecting the connecting part 41 to the front edge of the first recess 30 on the first surface 21a of the metal plate 21.

[0144] When manufacturing an organic EL display device with a pixel density of 450 ppi or higher, the dimension r2 of the through portion 42 is preferably set to 10 μm or more and 60 μm or less. This allows for the provision of a vapor deposition mask 20 capable of manufacturing high-pixel-density organic EL display devices. Preferably, the height r1 of the wall surface 31 of the first recess 30 is set to 6 μm or less.

[0145] Next, regarding Figure 10 The angle θ2 shown above will be explained. Angle θ2 corresponds to the maximum value of the tilt angle at which the vapor-deposited material 98, which is inclined relative to the normal direction N of the metal plate 21 and passes through the through-hole 42 near the connecting portion 41, can reach the organic EL substrate 92. This is because the vapor-deposited material 98, which passes through the connecting portion 41 at a tilt angle greater than angle θ2, will adhere to the wall surface 31 of the first recess 30 before reaching the organic EL substrate 92. Therefore, by reducing angle θ2, it is possible to suppress the adhesion of the vapor-deposited material 98, which passes through the through-hole 42 at a large tilt angle, to the organic EL substrate 92. This, in turn, can suppress the adhesion of the vapor-deposited material 98 to the outer part of the portion of the organic EL substrate 92 that overlaps with the through-hole 42. That is, reducing angle θ2 can suppress the deviation in the area and thickness of the vapor-deposited material 98 attached to the organic EL substrate 92. From this perspective, for example, the through-hole 25 is formed with an angle θ2 of 45 degrees or less. It should be noted that in Figure 10 The diagram shows an example where the size of the first recess 30 on the first surface 21a, i.e., the opening size of the through hole 25 on the first surface 21a, is larger than the size r2 of the first recess 30 on the connecting portion 41. That is, it shows an example where the angle θ2 is a positive value. However, although not shown, the size r2 of the first recess 30 on the connecting portion 41 can also be larger than the size of the first recess 30 on the first surface 21a. That is, the angle θ2 can also be a negative value.

[0146] Next, the method for manufacturing the vapor deposition mask 20 will be described.

[0147] First, the manufacturing method of the metal plate used to manufacture the vapor deposition mask will be described. In this embodiment, an example of the metal plate being made of a rolled material of a nickel-containing iron alloy will be described. The rolled material may have a thickness of 30 μm or less. In addition, the rolled material may contain 30% or more but less than 38% by mass of nickel, 0% or more but less than 6% by mass of cobalt, the remainder of iron, and unavoidable impurities.

[0148] First, iron, nickel, and other raw materials are prepared. For example, each raw material is prepared in a proportion of approximately 64% by weight for iron and approximately 36% by weight for nickel relative to the total raw material content. Next, the raw materials are pulverized as needed, and then a melting process is performed to melt the raw materials in a smelting furnace. For example, the raw materials are melted and mixed using a gas discharge such as an electric arc discharge. From this, a base material for metal sheets can be obtained.

[0149] The melting temperature is set according to the raw materials, for example, above 1500°C. The melting process may include the process of adding aluminum, manganese, silicon, etc., into the melting furnace for deoxidation, dehydration, denitrification, etc. In addition, the melting process can be carried out under low pressure conditions below atmospheric pressure and in an atmosphere of inert gases such as argon.

[0150] After the base material is removed from the smelting furnace, a grinding process can be performed to remove its surface. This removes the oxide coating, such as scale. There are no particular limitations on the specific grinding method; methods such as the grinding method (where a grinding wheel rotates to remove the surface of the base material) and the pressing method (where the base material is pressed into a cutting tool to remove its surface) can be used. The grinding process can be performed to achieve a uniform thickness of the base material.

[0151] Next, as Figure 11 As shown, a rolling process is performed on a base material 60 made of a nickel-containing iron alloy. For example, the material is conveyed towards a rolling apparatus 66 containing a pair of rolling rolls 66a and 66b (work rolls) while tensile tension is applied in the direction indicated by arrow D1. The base material 60, reaching between the rolling rolls 66a and 66b, is rolled using the pair of rolling rolls 66a and 66b, resulting in the base material 60 being stretched along the conveying direction while its thickness decreases. Thus, a metal sheet 64 of thickness T0 can be obtained. Figure 11 As shown, a wound body 62 can be formed by winding the metal plate 64 onto the core 61.

[0152] It should be noted that, Figure 11This only shows an overview of the rolling process and does not specifically limit the particular structure and steps used to perform the rolling process. For example, the rolling process may include: a hot rolling process in which the base material is processed at a temperature above the temperature at which the crystal arrangement of the ferroalloy constituting the base material 60 changes; and a cold rolling process in which the base material is processed at a temperature below the temperature at which the crystal arrangement of the ferroalloy changes. Furthermore, the direction in which the base material 60 or the metal sheet 64 passes between a pair of rolling rolls 66a, 66b is not limited to one direction. For example, in Figure 11 and Figure 12 In this process, the base material 60 or metal plate 64 is repeatedly passed between a pair of rolling rolls 66a and 66b in a direction from left to right and from right to left on the paper, thereby slowly rolling the base material 60 or metal plate 64.

[0153] In the rolling process, the surface roughness of the metal sheet 64 can be adjusted by changing the diameters of the rolling rolls 66a and 66b that contact the base material 60. For example, by reducing the diameters of the rolling rolls 66a and 66b, the volume of the pits (described later) present on the surface of the metal sheet 64 can be reduced. Thus, for example, the volumetric density of the pits (described later) can be adjusted to 15000 μm. 3 / mm 2 the following.

[0154] The diameter of the rolling roll is preferably 28 mm or more. The diameter of the rolling roll can be 40 mm or more, or 50 mm or more. Alternatively, the diameter of the rolling roll is preferably 150 mm or less. The diameter of the rolling roll can be 120 mm or less, 100 mm or less, or 80 mm or less.

[0155] The diameter of the rolling roll can be determined by a combination of any one of a plurality of upper limit candidate values ​​and any one of a plurality of lower limit candidate values. For example, the diameter of the rolling roll can be 28 mm or more and 150 mm or less, or 40 mm or more and 120 mm or less. Alternatively, the diameter of the rolling roll can be determined by a combination of any two of the plurality of upper limit candidate values. For example, the diameter of the rolling roll can be 120 mm or more and 150 mm or less. Furthermore, the diameter of the rolling roll can be determined by a combination of any two of the plurality of lower limit candidate values. For example, the diameter of the rolling roll can be 28 mm or more and 40 mm or less. Preferably, the diameter of the rolling roll is 28 mm or more and 150 mm or less, more preferably 40 mm or more and 120 mm or less, more preferably 50 mm or more and 100 mm or less, and even more preferably 50 mm or more and 80 mm or less.

[0156] In addition, during the rolling process, the pressure of the rolling regulator can be adjusted to adjust the shape of the metal sheet 64. Furthermore, in addition to the rolling rolls (work rolls) 66a and 66b, the shape of the support rolls can also be appropriately adjusted, and the position of the support rolls can also be appropriately adjusted in the width direction of the sheet.

[0157] Furthermore, the rolling speed, i.e., the feed speed of the base material, can be adjusted during the rolling process. It should be noted that, from the perspective of further reducing the volumetric density of the pit correction, it is preferable to slow down the rolling speed. By slowing down the rolling speed, the amount of rolling oil or other coolant drawn between the base material 60 and the rolling rolls 66a and 66b can be reduced. This, in turn, reduces the number and area of ​​oil pits formed on the surface of the metal sheet 64.

[0158] The rolling speed is preferably 30 m / min or higher. The rolling speed can be 50 m / min or higher, 70 m / min or higher, or 100 m / min or higher. Alternatively, the rolling speed is preferably 200 m / min or lower. The rolling speed can be 150 m / min or lower, 100 m / min or lower, or 80 m / min or lower.

[0159] The rolling speed can be determined by a combination of any one of several upper limit candidate values ​​and any one of several lower limit candidate values. For example, the rolling speed can be between 30 m / min and 200 m / min, or between 50 m / min and 150 m / min. Furthermore, the range of the rolling speed can be determined by a combination of any two of the several upper limit candidate values. For example, the rolling speed can be between 150 m / min and 200 m / min, or between 100 m / min and 150 m / min. Additionally, the range of the rolling speed can be determined by a combination of any two of the several lower limit candidate values. For example, the range of the rolling speed can be between 30 m / min and 50 m / min, or between 50 m / min and 70 m / min. The rolling speed is preferably 30 m / min to 200 m / min, more preferably 30 m / min to 150 m / min, even more preferably 30 m / min to 100 m / min, and even more preferably 30 m / min to 80 m / min.

[0160] Furthermore, during the cold rolling process, a coolant such as kerosene or neatoil can be supplied between the base material 60 and the rolling rolls 66a and 66b. This allows for control of the base material temperature. It should be noted that, from the perspective of further reducing the volumetric density of the pit correction, it is preferable to reduce the amount of coolant supplied.

[0161] Furthermore, by appropriately selecting a coolant, the number and area of ​​oil pits or rolling stripes formed on the surface of the metal sheet 64 can be adjusted. For example, purified oil can be used as a coolant. Purified oil has the characteristic that its viscosity is unlikely to increase during rolling. Therefore, by using purified oil as a coolant, the amount of coolant wound between the base material 60 and the rolling rolls 66a and 66b can be reduced. As a result, the formation of oil pits on the surface of the metal sheet 64 can be suppressed.

[0162] Furthermore, by appropriately selecting the surface roughness of the rolling rolls, the number and area of ​​oil pits or rolling stripes formed on the surface of the metal sheet 64 can be adjusted. For example, by reducing the surface roughness Ra of the rolling rolls, the formation of rolling stripes on the surface of the metal sheet 64 can be suppressed. The surface roughness Ra of the rolling rolls is preferably 0.2 μm or less. The surface roughness Ra of the rolling rolls can be 0.15 μm or less, 0.1 μm or less, or 0.05 μm or less. The surface roughness Rz of the rolling rolls is preferably 2.0 μm or less. The surface roughness Rx of the rolling rolls can be 1.5 μm or less, 1.0 μm or less, or 0.5 μm or less. Furthermore, the surface roughness Rz of the rolling rolls is preferably 2.0 μm or less. The surface roughness Rz of the rolling rolls can be 1.5 μm or less, 1.0 μm or less, or 0.5 μm or less. The surface roughness Ra and Rz are measured based on JIS B 0601:2013.

[0163] Furthermore, analytical processes can be performed before, during, or between rolling processes to analyze the quality or characteristics of the base material 60 or the metal sheet 64. For example, the base material 60 or the metal sheet 64 can be irradiated with fluorescent X-rays to analyze its composition. Additionally, the thermal expansion of the base material 60 or the metal sheet 64 can be determined using thermomechanical analysis (TMA).

[0164] Then, in order to remove the residual stress accumulated in the metal plate 64 due to rolling, such as Figure 12 As shown, an annealing process can be performed by annealing apparatus 67 to anneal the metal plate 64. For example... Figure 12 As shown, the annealing process can be performed simultaneously with stretching the metal sheet 64 in the conveying direction (length direction). That is, the annealing process can be performed as continuous annealing, not intermittent annealing, but rather during conveying. In this case, to suppress deformation such as bending and breakage of the metal sheet 64, it is preferable to set the temperature and conveying speed. By performing the annealing process, a metal sheet 64 with residual strain removed to some extent can be obtained. It should be noted that... Figure 12The illustration shows an example of conveying the metal plate 64 in the horizontal direction during the annealing process, but it is not limited to this. The metal plate 64 may also be conveyed in other directions such as the vertical direction during the annealing process.

[0165] The conditions for the annealing process are appropriately set according to the thickness and reduction rate of the metal plate 64. For example, the annealing process is carried out for 30 to 90 seconds within a temperature range of 500°C to 600°C. It should be noted that the aforementioned number of seconds represents the time required for the metal plate 64 to pass through the space within the annealing apparatus 67 adjusted to the specified temperature. The temperature of the annealing process is set to prevent softening of the metal plate 64.

[0166] The lower limit of the annealing process temperature can also be lower than the aforementioned 500°C. For example, the annealing process temperature can be above 400°C or above 450°C. Furthermore, the upper limit of the annealing process temperature can also be higher than the aforementioned 600°C. For example, the annealing process temperature can be below 700°C or below 650°C. Additionally, the range of the annealing process temperature can be determined by a combination of any one of the candidate values ​​for the upper limits and any one of the candidate values ​​for the lower limits. For example, the annealing process temperature can be above 400°C and below 700°C, or above 450°C and below 650°C. Furthermore, the range of the annealing process temperature can be determined by a combination of any two of the candidate values ​​for the upper limits. For example, the annealing process temperature can be above 650°C and below 700°C. Additionally, the range of the annealing process temperature can be determined by a combination of any two of the candidate values ​​for the lower limits. For example, the annealing process temperature can be above 400°C and below 450°C.

[0167] The annealing process can take 40 seconds or more, or 50 seconds or more. However, the lower limit of the annealing process time can also be shorter than the aforementioned 30 seconds. For example, the annealing process time can be 10 seconds or more, or 20 seconds or more. Furthermore, the annealing process time can be less than 80 seconds, less than 70 seconds, or less than 60 seconds. Additionally, the upper limit of the annealing process time can be longer than the aforementioned 90 seconds. For example, the annealing process time can be less than 100 seconds. Moreover, the range of the annealing process time can be determined by a combination of any one of the candidate values ​​for the upper limit and any one of the candidate values ​​for the lower limit. For example, the annealing process time can be 10 seconds or more but less than 100 seconds, 20 seconds or more but less than 90 seconds, 30 seconds or more but less than 80 seconds, 40 seconds or more but less than 70 seconds, or 50 seconds or more but less than 60 seconds. Furthermore, the range of the annealing process time can be determined by a combination of any two of the candidate values ​​for the upper limit. For example, the annealing process time can be 90 seconds or more but less than 100 seconds. Furthermore, the time range for the annealing process can be determined by any two of the aforementioned candidate lower limits. For example, the annealing process time can be between 10 and 20 seconds.

[0168] The annealing process described above is preferably performed in a non-reducing atmosphere or an inert gas atmosphere. Here, a non-reducing atmosphere refers to an atmosphere free of reducing gases such as hydrogen. "Free of reducing gases" means that the concentration of reducing gases such as hydrogen is 10% or less. In the annealing process, the concentration of reducing gases can be 8% or less, 6% or less, 4% or less, 2% or less, or 1% or less. Furthermore, an inert gas atmosphere refers to an atmosphere with a concentration of inert gases such as argon, helium, or nitrogen of 90% or more. In the annealing process, the concentration of inert gases can be 92% or more, 94% or more, 96% or more, 98% or more, or 99% or more. By performing the annealing process in a non-reducing atmosphere or an inert gas atmosphere, the formation of nickel compounds such as nickel hydroxide on the surface layer of the metal plate 64 can be suppressed. The annealing apparatus 67 may have a mechanism for monitoring the concentration of inert gases and a mechanism for adjusting the concentration of inert gases.

[0169] Before the annealing process, a cleaning process can be performed to clean the metal plate 64. This helps to prevent foreign matter from adhering to the surface of the metal plate 64 during the annealing process. For example, a hydrocarbon-based liquid can be used as the cleaning fluid.

[0170] In addition, Figure 12The example shown illustrates an annealing process performed while stretching the metal sheet 64 along its length. However, this is not a limitation; the annealing process can also be performed while the metal sheet 64 is wound onto the core 61. That is, batch annealing can be performed. It should be noted that when the annealing process is performed while the metal sheet 64 is wound onto the core 61, the metal sheet 64 may sometimes exhibit warping corresponding to the winding diameter of the winding body 62. Therefore, it is advantageous to perform the annealing process while stretching the metal sheet 64 along its length, depending on the winding diameter of the winding body 62 or the material constituting the base material 60.

[0171] Subsequently, to ensure that the width of the metal sheet 64 is within a specified range, a slitting process can be performed to cut off a specified range from both ends of the metal sheet 64 in the width direction obtained by the rolling process. This slitting process is performed to remove cracks that may have been generated at both ends of the metal sheet 64 due to rolling. By performing such a slitting process, it is possible to prevent the metal sheet 64 from breaking (so-called sheet cracking) starting from cracks.

[0172] Regarding the width of the portion cut off during the slitting process, it can be adjusted symmetrically in the width direction according to the shape of the metal plate 64 after the slitting process. Alternatively, the slitting process can be performed before the annealing process described above.

[0173] It should be noted that a long strip of metal 64 of a specified thickness can also be produced by repeating at least two of the above-mentioned rolling, annealing and slitting processes more than twice.

[0174] Additionally, after the rolling or annealing process, a visual inspection process can be performed to check the appearance of the metal sheet 64. This visual inspection process may include using an automatic inspection machine to check the appearance of the metal sheet 64. Alternatively, the visual inspection process may include visually inspecting the appearance of the metal sheet 64.

[0175] Additionally, a shape inspection process can be performed after the rolling or annealing process to check the shape of the metal sheet 64. For example, a three-dimensional measuring instrument can be used to measure the position of the surface of the metal sheet 64 in the thickness direction within a specified area of ​​the metal sheet 64.

[0176] In addition, the inventors conducted in-depth research and found that there are a large number of pits on the surface of the rolled metal plate 64. Figure 13This diagram illustrates a case where two or more pits 64c exist on the surface (e.g., the first surface 64a) of a metal sheet 64 obtained by rolling. The pits 64c are, for example, oil pits 64e or rolling stripes 64f. An oil pit 64e refers to a recess on the surface of the metal sheet 64 formed due to oil present between the base material 60 and the rolling rolls 66a, 66b. In this embodiment, a pit 64c refers to a recess with a depth of 0.2 μm or more among the oil pits 64e and other recesses present on the surface of the metal sheet 64. The density of pits 64c present on the surface of the metal sheet 64 is, for example, 3 pits / mm². 2 Above and 500 pieces / mm 2 It should be noted that the value of 0.2 μm is a preferred value for the correction distance dC, which will be described later. Furthermore, the size of the pit 64c in the face direction of the metal plate 64 is, for example, 1 μm or more and 60 μm or less.

[0177] As a technique for inspecting the surface undulations such as pits 64c on the surface of metal plate 64, a known technique is to calculate the arithmetic mean surface roughness Ra and the maximum profile height Ry. Both the arithmetic mean roughness Ra and the maximum profile height Ry are calculated using... Figure 13 The positions of the surface of the metal plate 64 in the thickness direction are determined by two or more points on a specified straight line such as R1 or R2. On the other hand, as shown... Figure 13 As shown, the density of pit 64c is sometimes uneven depending on the location. The result is, as... Figure 13 As shown, the density of pits 64c located on line R2 is significantly lower than the density of pits 64c located on line R1. Therefore, in techniques such as arithmetic mean roughness Ra and maximum profile height Ry, the deviation in inspection results becomes relatively large.

[0178] Furthermore, techniques such as arithmetic mean roughness Ra and maximum profile height Ry are considered insufficient to obtain information about the shape or volume of the pit 64c. Regarding issues such as arithmetic mean roughness Ra and maximum profile height Ry, refer to... Figure 14 Please provide an explanation. Figure 14 This is a diagram showing an example of a cross-section of the metal plate 64.

[0179] Figure 14Three types of recesses are shown. Recess 64c_1 on the left and recess 64c_2 in the center have the same opening diameter A. The wall of recess 64c_1 protrudes towards the metal plate. Conversely, the wall of recess 64c_2 protrudes outwards, unlike recess 64c_1. The two recesses 64c_3 on the right have an opening diameter A / 2. That is, the sum of the opening diameters of the two recesses 64c_3 is the same as the opening diameters of recesses 64c_1 and 64c_2. The depth of all three recesses 64c_1, 64c_2, and 64c_3 is B.

[0180] When the surface roughness caused by three types of pits 64c_1, 64c_2, and 64c_3 is measured using a measuring instrument, the arithmetic mean roughness Ra is expressed by the following formula.

[0181] Ra=∫A×B / 2dx

[0182] Therefore, the three types of pits, 64c_1, 64c_2, and 64c_3, have the same effect on the measured value of the arithmetic mean roughness Ra.

[0183] On the other hand, such as Figures 15-17 As shown, the dimensions of the through hole 25, the first recess 30, the second recess 35, the top 43, the rib, etc., formed by etching the metal plate 64 are affected not only by the depth of the pit 64c but also by the volume of the pit 64c. As described later, in this embodiment, the surface roughness is evaluated based on the volume of the pit. In this case, the three types of pits 64c_1, 64c_2, and 64c_3 have different degrees of influence on the pit correction volume density described later. Specifically, pit 64c_1 has the greatest influence on the pit correction volume density. In addition, the influence of one pit 64c_2 on the pit correction volume density is less than the influence of two pits 64c_3 on the pit correction volume density.

[0184] Figure 15 This illustrates etching the first resist pattern 65a as a mask from the first surface 64a side. Figure 14 The diagram shows a cross-sectional view of the process of forming the first recess 30 on the metal plate 64. The volume of the recess 64c_1 on the left is larger than the volume of the recess 64c_2 on the right. Therefore, compared to the location where the recess 64c_2 exists on the right, the etching of the recess 64c_1 on the left is performed earlier in both the thickness and surface directions of the metal plate 64. Consequently, the size of the first recess 30_1 formed at the location where the recess 64c_1 exists on the left is larger than the size of the first recess 30_2 formed at the location where the recess 64c_2 exists on the right.

[0185] Figure 16This illustrates etching the second resist pattern 65b as a mask from the second surface 64b side. Figure 15 The diagram shows a cross-sectional view of the process in which a second recess 35 communicating with the first recesses 30_1 and 30_2 is formed on the second surface 64b of the metal plate 64. Since the size of the first recess 30_1 on the left is larger than the size of the first recess 30_2 on the right, the size of the outline of the connecting portion 41 connecting the first recess 30_1 and the second recess 35 on the left is also larger than the size of the outline of the connecting portion 41 connecting the first recess 30_2 and the second recess 35 on the right.

[0186] Figure 17 This diagram illustrates the situation where the accuracy of the opening size of the through-hole 25 on the first surface 20a side is reduced due to the pit 64c of the metal plate 64. In the portion where the pit 64c has a large volume, the etching solution can penetrate into the interior of the pit 64c at the start of the etching process. Therefore, compared to other portions, etching can proceed earlier in the thickness and surface directions of the metal plate 64 in the portion where the pit 64c has a large volume. Therefore, for example, if a large pit 64c exists near the end of the opening of the first resist pattern 65a or the end of the opening of the second resist pattern 65b in the metal plate 64, the size of the through-hole 25 in the surface direction of the metal plate 64 will increase in the portion where the pit 64c exists. As a result, as... Figure 17 As shown by symbol 30_1, in the area where the large-volume recess 64c exists, the dimension r3 on the first surface 20a of the first recess 30 constituting the through hole 25 will deviate. Furthermore, the dimension r2 of the through portion 42 formed by the connecting portion 41 connecting the first recess 30 and the second recess 35 will also deviate. As a result, the dimensional accuracy and positional accuracy of the vapor-deposited material attached to the organic EL substrate 92 are considered to be reduced. It should be noted that this deviation in opening size will also occur in the second recess 35 on the second surface 20b side.

[0187] As described above, the ability to precisely form the through-hole 25 on the metal plate 64 depends not only on the depth of the recess 64c formed on the surface of the metal plate 64, but also significantly on the volume of the recess 64c. On the other hand, existing techniques based on arithmetic mean roughness Ra and the like cannot adequately obtain information about the volume of the recess 64c. Therefore, when inspecting the metal plate 64 using arithmetic mean roughness Ra, in order to prevent metal plates 64 unsuitable for manufacturing the vapor deposition mask 20 from passing inspection, a more stringent threshold for determining acceptance or rejection needs to be set than necessary. As a result, the yield of the metal plate 64 is considered to decrease.

[0188] To address this issue, this embodiment proposes to consider the volume of the recess 64c when inspecting the metal plate 64. This allows for a more accurate prediction of the degree of dimensional accuracy reduction in the through-hole 25 of the vapor deposition mask 20 caused by the recess 64c. Therefore, the metal plate 64 can be inspected without setting a more stringent threshold for acceptance or rejection, thus improving the yield of the metal plate 64. Hereinafter, refer to... Figure 18 and Figure 19 An example of an inspection procedure that takes into account the volume of pit 64c will be explained.

[0189] Figure 18 This is a top view showing an enlarged portion of the first surface 64a of the metal plate 64. Two or more recesses 64c are formed on the first surface 64a. Figure 19 In the diagram, symbol D1 indicates the conveying direction of the metal sheet 64 during the rolling process (hereinafter also referred to as the first direction). Additionally, symbol D2 indicates the direction perpendicular to the first direction D1 (hereinafter also referred to as the second direction).

[0190] During the inspection process, based on the location Figure 18 The quality of the metal plate 64 is determined by the volume of two or more pits 64c in the inspection area 711 of the first surface 64a. The area U1 of the inspection area 711 is, for example, 0.1 mm². 2 Above and 1.5mm 2 The following is done by making the area U1 of the inspection area 711 0.1 mm. 2 The above measures can suppress deviations in inspection results based on the position of the inspection area 711. Furthermore, by setting the area U1 of the inspection area 711 to 1.5 mm... 2 The following measures can prevent the examination from taking too long.

[0191] The inspection process includes a calculation step S1 and a judgment step S2. In the calculation step S1, the pit correction volume density is calculated. As demonstrated in the embodiments described later, the pit correction volume density is an indicator that is highly correlated with the dimensional accuracy of the components of the vapor deposition mask 20. In the judgment step, if the pit correction volume density is below a specified threshold, the metal plate 64 is judged to be good.

[0192] First, the calculation process S1 will be described. The calculation process S1 includes a measurement process S11 and a processing process S12. In the measurement process S11, firstly, as... Figure 18 As shown, images are taken in two or more unit regions 712, and the depth of the pit 64c is determined from the obtained images. For example, as... Figure 18 As shown, unit region 712 is a rectangular region with sides of length W1 and length W2. Unit region 712 corresponds to the range of an image that can be captured in a single shot. Figure 18 In the example shown, the side of length W1 is parallel to the first direction D1, and the side of length W2 is parallel to the second direction D2. For example, W1 is 270 μm and W2 is 202 μm. It should be noted that "the side of length W1 is parallel to the first direction D1" means that the angle between the side of length W1 and the first direction D1 is within the range of -10° to +10°. Similarly, "the side of length W2 is parallel to the second direction D2" means that the angle between the side of length W2 and the second direction D2 is within the range of -10° to +10°.

[0193] like Figure 18 As shown, two or more images are captured in the following manner: two adjacent unit regions 712 in the first direction D1 partially overlap, and two adjacent unit regions 712 in the second direction D2 also partially overlap. The two or more images obtained are then linked using image linking software, thereby obtaining an image with a wider area than a single unit region 712. Afterwards, the image obtained from the linking is, for example... Figure 18 The area indicated by the symbol 711 is extracted as the inspection area. For example, the inspection area 711 is determined as follows: enclosing... Figure 18 The nine unit regions 712 shown include one central unit region 712, which partially surrounds the other eight unit regions 712. The length of the inspection region 711 in the first direction D1 is, for example, 700 μm, and the length of the inspection region 711 in the second direction D2 is, for example, 500 μm.

[0194] exist Figure 18 In this text, the symbol 713 represents a pixel corresponding to the resolution of the inspection device. A pixel 713, for example, corresponds to a point on the metal plate 64 illuminated by a laser beam from the inspection device. The lengths W3 and W4 of the pixels 713 in the first direction D1 and the second direction D2 are preferably 0.1 μm or more and 0.4 μm or less. Furthermore, the area U2 of the pixel 713 is preferably 0.01 μm. 2 Above and 0.2μm 2 The following applies when the area of ​​unit region 712 is 270μm × 202μm, and the resolution of the first direction D1 and the second direction D2 of unit region 712 is 1024 × 768. The lengths W3 and W4 of pixels 713 in the first direction D1 and the second direction D2 are both 0.263μm. Furthermore, the area U2 of pixel 713 is 0.069μm. 2 .

[0195] Figure 19 This is a cross-sectional view showing a metal plate 64 with a recess 64c formed when cut parallel to the first direction D1. Figure 19In the image, the symbol d(k) represents the distance from the first surface 64a to the bottom surface of the pit 64c in pixel 713 located at coordinate x(k) in the first direction D1. k is an integer, and the range of k is determined by the resolution of the image.

[0196] It should be noted that, on the first surface 64a of the metal plate 64, except for Figure 19 Besides the clearly defined pit 64c, there may be minor unevenness or undulations. Therefore, when measuring the depth of the pit 64c using the first surface 64a as a reference, the measurement result of the pit 64c's depth will be deviated due to the state of the first surface 64a surrounding the pit 64c. Considering this issue, in the measurement step S11 and the processing step S12, the position of the first surface 64a in the thickness direction of the metal plate 64 can be taken as the position of a reference plane RP, which is an imaginary plane. The reference plane RP will be explained below.

[0197] The reference plane RP of the first surface 64a is, for example, a plane estimated by the least squares method. Specifically, firstly, the position of the inspection area 711 in the thickness direction of the surface of the first surface 64a of the metal plate 64 is determined using a laser microscope (described later). Next, the predetermined plane is temporarily set as the reference plane RP, and the square of the distance from the position on the surface of the first surface 64a to the reference plane RP is calculated in each pixel 713. In this case, the plane with the smallest sum of the squares of the distances can be used as the reference plane RP.

[0198] In the measurement process S11, such as Figure 19 As shown, in each pixel 713 of the inspection area 711, the depth d(k) of the pit 64c is measured. The measured value of the depth is the distance from the measured value of the position of the first surface 64a of the metal plate 64 in the thickness direction to the reference surface RP estimated by the least squares method.

[0199] As an inspection device used in the measurement process S11, a laser microscope can be used, for example. In the measurement using a laser microscope, firstly, a laser is irradiated onto the inspection area 711 of the first surface 64a of the metal plate 64. Next, the laser reflected from the inspection area 711 is used as a two-dimensional reflection image of the inspection area 711, which is then captured using a CCD or CMOS image sensor. Furthermore, based on the principle of confocal microscopy, the two-dimensional reflection image is analyzed to determine the position of each pixel 713 of the inspection area 711 in the thickness direction of the surface of the first surface 64a of the metal plate 64. For example, a VK-X200 series laser microscope manufactured by KEYENCE Corporation can be used as the laser microscope.

[0200] In the processing step S12, information about the volume of the pit 64c in the inspection area 711 is calculated based on the depth of the pit 64c measured in each pixel 713 within the inspection area 711.

[0201] In this embodiment, firstly, as Figure 19 As shown, a correction surface CP is set in the thickness direction of the metal plate 64, and this correction surface CP is located at a predetermined correction distance dC from the reference surface RP towards the second surface 64b. Next, the sum of the volumes of the portions of the pit 64c in the inspection area 711 located on the second surface 64b side relative to the correction distance dC in the thickness direction of the metal plate 64 is calculated. For example, for the portion of the pit 64c in the inspection area 711 with a depth greater than the correction distance dC, the value d(k) - dC, which is the depth d(k) minus the correction distance dC, is calculated. Then, the value d(k) - dC is multiplied by the area U2 of the pixel 713. Therefore, in each pixel 713, the volume V(k) of the portion of the pit 64c relative to the side of the correction surface CP located on the second surface 64b is calculated (={(d(k)-dC)×U2}). Then, each volume V(k) is accumulated over the entire area of ​​the inspection region 711. Thus, the sum of the volumes of the portion of the pit 64c located in the inspection region 711 relative to the side of the correction surface CP located on the second surface 64b (hereinafter also referred to as the pit correction volume) V1 can be calculated.

[0202] Next, the pit correction volume V1 is divided by the area U1 of the inspection area 711. From this, the pit correction volume per unit area (hereinafter also referred to as pit correction volume density) V2 can be calculated.

[0203] The aforementioned correction distance dC is preferably 0.1 μm or more and 0.5 μm or less, for example, 0.2 μm. By appropriately setting the correction distance dC and calculating the pit correction volume density V2, as demonstrated in the embodiments described later, the correlation between the pit correction volume density V2 and the dimensional accuracy of the constituent elements of the vapor deposition mask 20 can be improved. It should be noted that in the following description, the pit correction volume V1 and pit correction volume density V2 obtained when the correction distance dC is z μm are sometimes referred to as pit correction volume V1 (z μm) and pit correction volume density V2 (z μm), respectively. For example, when the correction distance dC is 0.2 μm, the expressions pit correction volume V1 (0.2 μm) and pit correction volume density V2 (0.2 μm) are sometimes used.

[0204] Next, the following judgment step S2 is performed: if the pit correction volume density V2 is below the specified threshold TH1, the metal plate 64 is judged to be good. Thus, metal plates 64 that can form the components of the vapor deposition mask 20 such as through holes 25 with good precision can be selected.

[0205] The threshold TH1 is appropriately set based on the dimensional accuracy required by the constituent elements of the vapor deposition mask 20, or the setting of the correction distance dC. For example, if the error of the opening size of the through hole 25 of the vapor deposition mask 20, such as the size r3 of the first recess 30 and the size r2 of the through portion 42, is required to be ±1.0 μm or less, and the correction distance dC is 0.2 μm, the threshold TH1 can be set to 15000 μm. 3 / mm 2 The threshold TH1 can be 12000 μm. 3 / mm 2 It can be 10000μm 3 / mm 2 It can be 9000μm 3 / mm 2 It can be 6000μm 3 / mm 2 It can be 5000μm 3 / mm 2 It can be up to 3000μm 3 / mm 2 It can also be 1000μm 3 / mm 2 .

[0206] In judgment step S2, if the pit correction volume density V2 is above threshold TH2 and below threshold TH1, the metal plate 64 can be judged to be good. That is, in addition to using threshold TH1, which specifies the upper limit of pit correction volume density V2, judgment step S2 also uses threshold TH2, which specifies the lower limit of pit correction volume density V2. By making the metal plate 64 have a pit correction volume density V2 above threshold TH2, the adhesion of the resist film to the surface of the metal plate 64 can be improved. The upper threshold TH1 can be called the first threshold, and the lower threshold TH2 can be called the second threshold. The threshold TH2 can be 10 μm. 3 / mm 2 It can be 100μm 3 / mm 2 It can be 500μm 3 / mm 2 It can be 1000μm 3 / mm 2 It can be up to 3000μm 3 / mm 2 It can be 4000μm 3 / mm 2 It can also be 5000μm 3 / mm 2 .

[0207] The range of the pit correction volumetric density V2 of the metal plate 64 judged as good in the judgment process S2 can be determined by a combination of any one of the candidates for the upper limit threshold TH1 and any one of the candidates for the lower limit threshold TH2. For example, the pit correction volumetric density V2 of the metal plate 64 judged as good, that is, the screened metal plate 64, can be 10 μm. 3 / mm 2 Above 15000μm 3 / mm 2 The following can be 100μm 3 / mm 2 Above 12000μm 3 / mm 2 The following can be 500μm 3 / mm 2 Above 10000μm 3 / mm 2 The following can be 1000μm 3 / mm 2 Above 9000μm 3 / mm 2 The following can be 3000μm 3 / mm 2 Above 6000μm 3 / mm 2 The following can also be 4000μm 3 / mm 2 Above 6000μm 3 / mm 2 The following applies. Furthermore, the range of the pit-corrected volumetric density V2 of the selected metal plate 64 can be determined by any two of the candidates for the upper limit threshold TH1 mentioned above. For example, the pit-corrected volumetric density V2 of the selected metal plate 64 can be 12000 μm. 3 / mm 2 Above 15000μm 3 / mm 2 The following applies. Furthermore, the range of the pit-corrected volumetric density V2 of the selected metal plate 64 can be determined by any two of the candidate thresholds TH2 of the aforementioned plurality of lower limits. For example, the pit-corrected volumetric density V2 of the selected metal plate 64 can be 10 μm. 3 / mm 2 Above 100μm 3 / mm 2 the following.

[0208] Figure 39It is a diagram showing an example of the distribution of the pit correction volume density V2 of two or more metal plates 64 selected based on the determination condition that a metal plate with a pit correction volume density V2 of less than or equal to the threshold value TH1 is determined as a qualified product. In Figure 39 the horizontal axis represents the value of the pit correction volume density V2 calculated for each metal plate 64. In addition, the vertical axis represents the number of metal plates 64 having a pit correction volume density V2 within the range shown on the horizontal axis. For example, among the two or more selected metal plates 64, the number of metal plates 64 having a pit correction volume density V2 of 3 / mm 2 more than 6000μm 3 / mm 2 and less than 9000μm is 17.

[0209] In Figure 39 the example, the threshold value TH1 is 15000μm 3 / mm 2 . In this case, most (for example, more than 95%) of the metal plates 64 determined as qualified products have a pit correction volume density V2 of 3 / mm 2 or less. It should be noted that as Figure 39 shown, due to measurement errors, etc., a part of the selected metal plates 64 sometimes has a pit correction volume density V2 exceeding 15000μm 3 / mm 2 .

[0210] Figure 40 It is a diagram showing an example of the distribution of the pit correction volume density V2 of two or more metal plates 64 selected based on the determination condition that a metal plate with a pit correction volume density V2 greater than or equal to the threshold value TH2 and less than or equal to the threshold value TH1 is determined as a qualified product. Figure 40 The meanings of the horizontal axis and the vertical axis shown are the same as those in Figure 39 . In Figure 40 the example, the threshold value TH2 is 3000μm 3 / mm 2 , and the threshold value TH1 is 15000μm 3 / mm 2 . Thus, in Figure 40 the example, compared with the example of Figure 39 , the range of the metal plates 64 selected as qualified products is narrower. In this case, if the screening shown in Figure 40 is implemented, then the screening shown in Figure 39 is also implemented.

[0211] The above description illustrates an example of using an inspection process to examine the metal plate 64 based on the pit-corrected volumetric density V2 to determine the quality of the metal plate 64, i.e., to screen the metal plate 64. That is, it illustrates an example of the inspection process functioning as a screening process for the metal plate 64 in the manufacturing method of the metal plate 64. However, the inspection process may also be used for purposes other than screening the metal plate 64 in the manufacturing method of the metal plate 64.

[0212] It should be noted that the screening conditions in the screening process are arbitrary. For example, the screening process can screen out metal plates 64 with a pit-corrected volumetric density V2 that falls within the range determined by a combination of any one of the candidates for the multiple upper limit thresholds TH1 and any one of the candidates for the multiple lower limit thresholds TH2. Alternatively, the screening process can screen out metal plates 64 with a pit-corrected volumetric density V2 that falls within the range determined by a combination of any two of the candidates for the multiple upper limit thresholds TH1. Similarly, the screening process can screen out metal plates 64 with a pit-corrected volumetric density V2 that falls within the range determined by a combination of any two of the candidates for the multiple lower limit thresholds TH2.

[0213] An example of using an inspection process for purposes other than screening of the metal sheet 64 in the manufacturing process of the metal sheet 64 will be described. For example, the inspection process can be used to optimize the conditions used for manufacturing the metal sheet 64, such as the rolling rate or the amount of oil. Specifically, the inspection process can be used to manufacture the metal sheet 64 with various rolling rates and amounts of oil, calculate the pit correction volumetric density V2 of each obtained metal sheet 64, and set appropriate manufacturing conditions that can reduce the pit correction volumetric density V2. In this case, it is not necessary to perform screening based on the inspection process on all the metal sheets 64 in the manufacturing process of the metal sheet 64. For example, the inspection process can be performed only on a portion of the metal sheets 64. Alternatively, once the manufacturing conditions are set, the inspection process can be omitted entirely.

[0214] Figure 41 This is a diagram illustrating an example of the distribution of the pit correction volumetric density V2 of two or more metal plates 64 manufactured under manufacturing conditions discovered based on the judgment condition that a metal plate with a pit correction volumetric density V2 below the threshold TH1 is determined to be a qualified product. Figure 41 The meanings of the horizontal and vertical axes shown are as follows: Figure 39 The situation is the same. Figure 41 In the example, the threshold TH1 is 15000μm 3 / mm 2 .exist Figure 41 In the example, even without a screening process, the two or more metal plates 64 manufactured have a diameter of 15000 μm. 3 / mm 2 The following is the corrected volumetric density V2 for the pit.

[0215] According to the metal plate manufacturing method of this embodiment, a metal plate 64 having a pit-corrected volumetric density V2 that satisfies the above-described determination criteria can be obtained. For example, a metal plate with a pit correction volumetric density V2 of 15000 μm can be obtained. 3 / mm 2 The following is a metal plate 64 with a recessed volumetric density V2. This suppresses the reduction in dimensional accuracy of the through-holes 25 of the vapor deposition mask 20 caused by the recesses 64c. Consequently, the dimensional and positional accuracy of the vapor-deposited material attached to the organic EL substrate 92 through the through-holes 25 can be improved.

[0216] Next, mainly refer to Figures 20-28 The method for manufacturing a vapor deposition mask 20 using the qualified metal plate 64 from the above inspection process is explained. Figure 20 This is a diagram showing a manufacturing apparatus 70 for fabricating a vapor deposition mask 20 using a metal plate 64. First, a wound body 62 is prepared, onto a core 61, to wind the metal plate 64. Then, the core 61 is rotated to unwind the wound body 62, thereby achieving the desired shape. Figure 20 As shown, a strip of metal plate 64 is supplied.

[0217] The supplied metal plate 64 is sequentially conveyed to the processing unit 72 and the separation unit 73 via the conveyor roller 75. The processing unit 72 performs the following processing steps: processing the metal plate 64 that has passed the inspection step to form through holes 25 in the metal plate 64. It should be noted that in this embodiment, multiple through holes 25 corresponding to multiple vapor deposition masks 20 are formed in the metal plate 64. In other words, multiple vapor deposition masks 20 are distributed to the metal plate 64. The separation unit 73 performs the following separation step: separating the portion of the metal plate 64 with two or more through holes 25 corresponding to one vapor deposition mask 20 from the metal plate 64. In this way, a thin sheet-like vapor deposition mask 20 can be obtained.

[0218] Reference Figures 20-28The processing steps are described below. The processing steps include: etching a strip-shaped metal plate 64 using photolithography to form a first recess 30 on the metal plate 64 from the first surface 64a side; and etching a strip-shaped metal plate 64 using photolithography to form a second recess 35 on the metal plate 64 from the second surface 64b side. Furthermore, the first recess 30 and the second recess 35 formed on the metal plate 64 are made interconnected, thereby creating a through hole 25 in the metal plate 64. In the example described below, the formation step of the first recess 30 is performed before the formation step of the second recess 35, and a sealing step of the formed first recess 30 is performed between the formation steps of the first recess 30 and the second recess 35. The details of each step are described below.

[0219] First, such as Figure 21 As shown, resist films 65c and 65d comprising a negatively typed 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 comprising a photosensitive resist material such as casein is applied to 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 and 65d. Alternatively, a dry film may be attached to the first surface 64a and the second surface 64b of the metal plate 64 to form the resist films 65c and 65d. The dry film comprises, for example, an acrylic photocurable resin.

[0220] Next, prepare exposure masks 68a and 68b to prevent light from passing through the areas to be removed in the resist films 65c and 65d, such as... Figure 22 As shown, exposure masks 68a and 68b are respectively disposed on resist films 65c and 65d. At this time, an alignment process can be performed to adjust the relative positional relationship between the exposure mask 68a on the first surface 64a side and the exposure mask 68b on the second surface 64b side. For example, glass plates that prevent light from passing through the areas to be removed in the resist films 65c and 65d are used as exposure masks 68a and 68b. Then, vacuum sealing is used to ensure that the exposure masks 68a and 68b are fully sealed to the resist films 65c and 65d.

[0221] It should be noted that positive photosensitive resists can also be used as photosensitive resists. In this case, an exposure mask is used as the exposure mask to allow light to pass through the area in the resist film that is to be removed.

[0222] Subsequently, the resist films 65c and 65d are exposed through exposure masks 68a and 68b (exposure process). Furthermore, in order to form an image on the exposed resist films 65c and 65d, the resist films 65c and 65d are developed (development process). As described above, Figure 23As shown, 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. It should be noted that the developing process may also include a resist heat treatment process, which is used to increase the hardness of the resist films 65c and 65d, or to make the resist films 65c and 65d adhere more firmly to the metal plate 64. The resist heat treatment process can, for example, be performed above room temperature and below 400°C.

[0223] Next, as Figure 24 As shown, a first-side etching process is performed: the area of ​​the first side 64a of the metal plate 64 not covered by the first resist pattern 65a is etched using a first etching solution. For example, the first etching solution is sprayed onto the first side 64a of the metal plate 64 through the first resist pattern 65a from a nozzle positioned facing the first side 64a of the conveyed metal plate 64. The result is as follows: Figure 24 As shown, in the area of ​​the metal plate 64 not covered by the first resist pattern 65a, erosion occurs due to the first etching solution. This results in a large number of first recesses 30 being formed on the first surface 64a of the metal plate 64. The first etching solution used is, for example, an etching solution containing ferric chloride solution and hydrochloric acid.

[0224] After that, as Figure 25 As shown, the first recess 30 is coated with a resin 69 that is resistant to the second etching solution used in the subsequent second-side etching process. That is, the first recess 30 is sealed using the resin 69 that is resistant to the second etching solution. Figure 25 In the example shown, the resin 69 film is formed in such a way that it not only covers the first recess 30 but also the first surface 64a (first resist pattern 65a).

[0225] Next, as Figure 26 As shown, a second etching process is performed: the area in the second surface 64b of the metal plate 64 not covered by the second resist pattern 65b is etched to form a second recess 35 in the second surface 64b. The second etching process is performed until the first recess 30 and the second recess 35 communicate with each other, thereby forming a through hole 25. As the second etching solution, similar to the first etching solution described above, an etching solution containing, for example, ferric chloride solution and hydrochloric acid is used.

[0226] It should be noted that the erosion caused by the second etching solution occurs in the portion of the metal plate 64 that is in contact with the second etching solution. Therefore, the erosion occurs not only in the normal direction N (thickness direction) of the metal plate 64, but also along the direction of the surface of the metal plate 64. Here, the second-side etching process preferably ends before the two second recesses 35, which are respectively formed at positions facing each other with the two adjacent holes 67b of the second resist pattern 65b, converge on the back side of the bridge portion 67a located between the two holes 67b. Thus, as Figure 27 As shown, the aforementioned top 43 can remain on the second side 64b of the metal plate 64.

[0227] After that, as Figure 28 As shown, resin 69 is removed from metal plate 64. Resin 69 can be removed, for example, by using an alkaline stripping solution. When using an alkaline stripping solution, such as... Figure 28 As shown, resist patterns 65a and 65b are also removed simultaneously with resin 69. It should be noted that after removing resin 69, a different stripping solution than that used to strip resin 69 can be used to remove resist patterns 65a and 65b separately from resin 69.

[0228] Then, the portion of the metal plate 64 having two or more through holes 25 corresponding to a vapor deposition mask 20 is separated from the metal plate 64, thereby obtaining the vapor deposition mask 20.

[0229] Next, the method for manufacturing the vapor deposition mask apparatus 10 by combining the vapor deposition mask 20 and the frame 15 will be described. First, the frame 15 is prepared. Next, the second surface 20b of the vapor deposition mask 20 is fixed to the frame 15 by welding or the like. For example, first, with the frame 15 and the vapor deposition mask 20 overlapping, the vapor deposition mask 20 is photographed from the first surface 20a side using a camera or the like. At this time, tension can be applied to the vapor deposition mask 20. Next, based on the image obtained by the photograph, the position of the vapor deposition mask 20 relative to the frame 15 is detected. For example, the position of the outline of the vapor deposition mask 20 in the length direction D1 is detected. Next, the position of the vapor deposition mask 20 is adjusted so that the position of the vapor deposition mask 20 relative to the frame 15 is a predetermined position.

[0230] Next, the deposition method for depositing deposition material 98 on a substrate such as an organic EL substrate 92 using a deposition mask 20 will be described. First, the deposition mask apparatus 10 is arranged so that the deposition mask 20 faces the organic EL substrate 92. Then, 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 carried toward the organic EL substrate 92 through the deposition mask 20, thereby allowing the deposition material 98 to adhere to the organic EL substrate 92 in a pattern corresponding to the through-holes 25 of the deposition mask 20.

[0231] In the manufacturing method of the vapor deposition mask 20 of this embodiment, the vapor deposition mask 20 is manufactured using a metal plate 64 that has passed an inspection process based on the total volume of the recesses 64c formed on the surface of the metal plate 64. Therefore, the reduction in dimensional accuracy of the through-holes 25 of the vapor deposition mask 20 due to the recesses 64c can be suppressed. Consequently, the dimensional and positional accuracy of the vapor deposition material attached to the organic EL substrate 92 through the through-holes 25 can be improved.

[0232] It should be noted that various modifications can be made to the above embodiments. Hereinafter, variations will be described with reference to the accompanying drawings as needed. In the following description and the accompanying drawings used in the description, parts that can be constructed in the same way as the corresponding parts in the above embodiments are represented by the same symbols as those used in the above embodiments, so as to omit repeated descriptions. Furthermore, where the effects obtained in the above embodiments are obvious and can also be obtained in the variations, their descriptions are sometimes omitted.

[0233] In the above embodiment, during the inspection process, an example is shown where the first surface 64a of the metal plate 64, where the first recess 30 is formed, is the object of inspection. However, this is not a limitation; during the inspection process, the second surface 64b of the metal plate 64, where the second recess 35 is formed, may also be the object of inspection. Alternatively, both the first surface 64a and the second surface 64b of the metal plate 64 may be the object of inspection.

[0234] In the above embodiments, an example is shown of performing the inspection process of the metal plate 64 using equipment different from the equipment used in the manufacturing method of the vapor deposition mask 20, such as the processing steps or separation steps described above. In other words, an example is shown where the inspection process of the metal plate 64 is a step in the manufacturing method of the metal plate 64. However, this is not a limitation; the inspection process of the metal plate 64 can also be performed in the equipment used in the manufacturing method of the vapor deposition mask 20. In other words, the inspection process of the metal plate 64 can also be a step in the manufacturing method of the vapor deposition mask 20.

[0235] Furthermore, in the above embodiment, the pit correction volume density of the surface of the metal plate 64 before the through hole 25 is shown to be 15000 μm. 3 / mm 2 The following is an example. In the metal plate 64 after the through hole 25 is formed, i.e., in the metal plate 21 of the vapor deposition mask 20, the surface pit correction volume density can also be 15000 μm. 3 / mm 2As described above, during the etching process, the portion of the metal plate 64 where the through-hole 25 is not formed is covered by the resist pattern. Therefore, in the portion of the metal plate 21 of the vapor deposition mask 20 located at the edges 17a, 17b and the surrounding area 23, there will be pits 64c that are the same as those in the metal plate 64 before the through-hole 25 was formed. Therefore, the portion of the edges 17a, 17b and the surrounding area 23 on the surface of the metal plate 21 of the vapor deposition mask 20 can be designated as an inspection area, and the above-described inspection process taking into account the volume of the pits 64c can be performed, thereby calculating the pit correction volume density on the surface of the metal plate 21 of the vapor deposition mask 20.

[0236] Example

[0237] The embodiments of this application will be described in more detail below, but the embodiments of this application are not limited to those described in the following embodiments as long as they do not go beyond the essential points.

[0238] (First inspection case)

[0239] First, a base material is prepared, consisting of an iron alloy containing 36% by mass of nickel and the remainder of iron and unavoidable impurities. Next, the base material is subjected to the rolling, slitting, and annealing processes described above, thereby producing two types of wound bodies (hereinafter referred to as Sample 1 and Sample 2) with a strip of metal having a thickness of 15 μm. Similarly, seven types of wound bodies (hereinafter referred to as Sample 3 to Sample 10) with a strip of metal having a thickness of 20 μm are produced.

[0240] Next, the aforementioned inspection procedure of checking the surface undulation of each sample is performed. First, a sample is cut out from the center of its width direction to create a square test piece with one side of 5 cm. Next, a measurement procedure is performed: using a laser microscope, the position of the surface in each pixel 713 of the inspection area 711 of the test piece is measured. The laser microscope used is a VK-X200 series laser microscope manufactured by KEYENCE Corporation.

[0241] The laser microscope settings for measuring the position of the sample surface are as follows.

[0242] • Laser: Blue (wavelength 408nm)

[0243] Objective lens: 50x

[0244] • Optical zoom: 1.0x

[0245] • Measurement mode: Surface shape

[0246] • Measurement size: Standard (1024×768)

[0247] • Quality Measurement: High Speed

[0248] •RPD: Yes

[0249] • Test piece fixing method: Place it on the KOKUYO magnetic sheet

[0250] RPD stands for Real Peak Detection. "RPD: Yes" refers to a method that uses the detection of the peak of the reflected light from a laser to determine the position of the sample surface.

[0251] The area of ​​inspection area 711 is explained below. For samples 1 through 4 and samples 7 through 10, the nine areas (images) measured under the aforementioned "standard (1024×768)" setting are linked together to form inspection area 711. In this case, the area U1 of inspection area 711 is 0.35 mm². 2 Furthermore, for samples 5 and 6, the four regions (images) measured under the aforementioned "standard (1024×768)" setting will be linked together to form inspection region 711. In this case, the area U1 of inspection region 711 is 0.175 mm². 2 .

[0252] Next, the processing steps are performed: Based on the measurement results, the pit correction volume V1 and pit correction volume density V2 of the specimen surface are calculated. First, using the [Reference Plane Setting] function of the laser microscope, the aforementioned reference plane RP is calculated based on the least squares method. At this time, no region is specified; the entire object is treated as the target. Other settings for the laser microscope are described below.

[0253] [Surface Shape Correction] Includes correction methods: ripple removal, correction intensity: 5.

[0254] [Smoothing] Size: 3×3, Type: Simple Average

[0255] [High-level cutting]

[0256] Next, based on the measurement results of the surface position of the specimens obtained from the samples and the calculation results of the reference plane RP, the pit correction volume V1 and pit correction volume density V2 of each specimen are calculated. At this time, the correction distance dC between the reference plane RP and the correction plane CP is set to 0.2 μm. The calculation results of the pit correction volume density V2 are shown below. Figure 29 .

[0257] Next, the thin sheet-shaped metal plates 21 cut from the above samples are etched to form patterns of recesses and ribs on each metal plate 21, and the dimensional accuracy of the patterns at this time is evaluated. Figure 30 This is a top view showing an example of the pattern formed on the recesses 81 and ribs 82 of each metal plate 21. Additionally, Figure 31 yes Figure 30 The cross-sectional view of the metal plate 21 shown. Figure 30 and Figure 31 In the example shown, the metal plate 21 is etched to form a recess 81 such that the rib 82, extending along the first direction D1, remains in the metal plate 21. In the direction perpendicular to the direction in which the rib 82 extends (here, the rolling direction D1) (here, the width direction D2), the designed values ​​for the dimensions Z1 of the recess 81 and Z2 of the rib 82 are 30 μm.

[0258] Next, the width of the ribs 82 formed on each metal plate 21 was measured using a laser microscope. Specifically, the width of the ribs 82 was measured at a total of 25 locations at 2 μm intervals along the direction in which the ribs 82 extend (here, the first direction D1). Furthermore, three times the standard deviation of the measured width of the ribs 82 at the 25 locations (also denoted as 3σ(D1) below) was calculated. The values ​​of 3σ(D1) for the metal plates 21 cut from each sample are shown above. Figure 29 middle.

[0259] As a laser microscope, a laser microscope manufactured by KEYENCE Corporation, which is equipped with a measuring unit and a control unit, is used. The measuring unit is model VK-X160, and the control unit is model VK-X150.

[0260] The laser microscope settings for measuring the width of rib 82 are as follows.

[0261] Brightness: 7140

[0262] • Measurement mode: Surface shape

[0263] • Measurement dimensions: High precision (2048×1536)

[0264] • Measurement quality: High precision

[0265] • Aperture and shutter speed: Open

[0266] Laser shutter: Open

[0267] • Objective lens: 100x

[0268] • Optical zoom: 1.0x

[0269] • Measurement: Reflectance measurement

[0270] • Width measurement repeatability: 3σ = 0.03 μm

[0271] Next, the thin sheet-shaped metal plates 21 cut from the above samples are used in conjunction with... Figure 30The examples shown depict different patterns etched to form recesses 81 and ribs 82 on each metal plate 21. Specifically, as... Figure 32 As shown, the metal plate 21 was etched to form a recess 81, with the rib 82 extending along the second direction D2 remaining in the metal plate 21. Next, the width of the rib 82 formed on each metal plate 21 was measured using a laser microscope. Specifically, the width of the rib 82 was measured at a total of 25 locations at 2 μm intervals along the direction in which the rib 82 extends (here, the second direction D2). Furthermore, three times the standard deviation of the measured width of the rib 82 at the 25 locations (also denoted as 3σ(D2) below) was calculated. The values ​​of 3σ(D2) for the metal plates 21 cut from each sample are shown above. Figure 29 middle.

[0272] Furthermore, for the metal plates 21 cut from each sample, the average value 3σ(ave) of the aforementioned 3σ(D1) and 3σ(D2) was calculated. The values ​​of 3σ(ave) for the metal plates 21 cut from each sample are shown above. Figure 29 .

[0273] Next, the correlation coefficient R between the calculated pit-corrected volumetric density V2 (0.2 μm) and the 3σ (ave) width of rib 82 for each sample was determined. 2 The correlation coefficient R was obtained. 2 It is 0.8081. Figure 33 This is a scatter plot showing the correlation between the pit correction volume density V2 (0.2 μm) and the 3σ (ave) of the width of rib 82.

[0274] (Examples 2 through 5)

[0275] The correction distance dC between the reference plane RP and the correction plane CP is changed. Otherwise, similar to the first inspection example described above, the surface undulation of the first to tenth samples is inspected based on the pit correction volume density V2. Specifically, in the second inspection example, the correction distance dC is set to 0.1 μm, and the pit correction volume density V2 (0.1 μm) is calculated. In the third inspection example, the correction distance dC is set to 0.3 μm, and the pit correction volume density V2 (0.3 μm) is calculated. In the fourth inspection example, the correction distance dC is set to 0.4 μm, and the pit correction volume density V2 (0.4 μm) is calculated. In the fifth inspection example, the correction distance dC is set to 0.5 μm, and the pit correction volume density V2 (0.5 μm) is calculated. The calculated results of the pit correction volumetric density V2 (0.1 μm), V2 (0.3 μm), V2 (0.4 μm), and V2 (0.5 μm) for each sample are presented together with the above-mentioned pit correction volumetric density V2 (0.2 μm). Figure 34 .

[0276] Next, the correlation coefficient R between the calculated pit correction volume density V2 (0.1 μm) for each sample and the 3σ (ave) of the width of rib 82 was determined. 2 The correlation coefficient R was obtained. 2 It is 0.0136. Figure 35 This is a scatter plot showing the correlation between the pit correction volume density V2 (0.1 μm) and the 3σ (ave) of the width of rib 82.

[0277] In addition, the correlation coefficient R between the calculated pit correction volume density V2 (0.3 μm) and the 3σ (ave) width of rib 82 for each sample was determined. 2 The correlation coefficient R was obtained. 2 It is 0.6653. Figure 36 This is a scatter plot showing the correlation between the pit correction volume density V2 (0.3 μm) and the 3σ (ave) of the width of rib 82.

[0278] In addition, the correlation coefficient R between the calculated pit correction volume density V2 (0.4 μm) and the 3σ (ave) width of rib 82 for each sample was determined. 2 The correlation coefficient R was obtained. 2 It is 0.4811. Figure 37 This is a scatter plot showing the correlation between the pit correction volumetric density V2 (0.4 μm) and the 3σ (ave) of the width of rib 82.

[0279] In addition, the correlation coefficient R between the calculated pit correction volume density V2 (0.5 μm) and the 3σ (ave) width of rib 82 for each sample was determined.2 The correlation coefficient R was obtained. 2 It is 0.3791. Figure 38 This is a scatter plot showing the correlation between the pit correction volume density V2 (0.5 μm) and the 3σ (ave) of the width of rib 82.

[0280] According to the first inspection example, the surface undulation of the metal plate is inspected based on the volume of the pit, thereby obtaining an index that is highly correlated with the dimensional accuracy of the rib 82 formed by etching.

[0281] Furthermore, a comparison between the first inspection example and the second to fifth inspection examples above shows that, according to the first inspection example, by setting the correction distance dC between the reference surface RP and the correction surface CP to 0.2 μm, an index that is highly correlated with the dimensional accuracy of the rib 82 formed by etching can be obtained.

[0282] In the second inspection example where the correction distance dC was set to 0.1 μm, because the correction distance dC was too small, not only were specific pits that significantly affected the dimensional accuracy of rib 82 detected, but also pits that had almost no effect on the dimensional accuracy of rib 82 were detected. As a result, the correlation coefficient was considered to be reduced. In the third to fifth inspection examples where the correction distance dC was set to 0.3 μm or more, because the correction distance dC was too large, when evaluating relatively smooth metal plates with low pit density, the differences in pit density and size could not be properly reflected by the pit correction volumetric density V2. As a result, the correlation coefficient was considered to be reduced.

Claims

1. A method for manufacturing a metal plate, which is a method for manufacturing a metal plate used to manufacture a vapor deposition mask, wherein, The method for manufacturing the metal sheet includes a rolling process, wherein the metal sheet is obtained by rolling a base material. The metal plate has two or more recesses located on the surface of the metal plate. When the sum of the volumes of the portions of two or more pits located on a portion of the surface that are at least 0.2 μm away from the reference plane in the thickness direction of the metal plate is defined as the pit correction volume, the pit correction volume density calculated by dividing the pit correction volume by the area of ​​the portion of the surface is 15000 μm. 3 / mm 2 Hereinafter, the reference plane is the plane estimated from the surface using the least squares method. The pit correction volume is calculated based on the results obtained by measuring the depth of the pit at various locations on the portion of the surface using a laser microscope. The area of ​​the portion of the surface is 0.1 mm. 2 above.

2. The method for manufacturing a metal plate as described in claim 1, wherein, The corrected volumetric density of the pit is 10 μm. 3 / mm 2 above.

3. The method for manufacturing a metal plate as described in claim 1 or 2, wherein, The metal plate is made of a nickel-containing iron alloy.

4. A method for manufacturing a vapor deposition mask, comprising a method for manufacturing a vapor deposition mask having two or more through holes, wherein, The manufacturing method includes the following steps: The process of preparing a metal plate that includes a first side and a second side; The process of forming an anti-corrosion film on the first and second surfaces of the metal plate; The process of exposing the resist film; The process of developing the exposed resist film to form a first resist pattern on the first surface and a second resist pattern on the second surface; A process of heat-treating the first and second resist patterns at a temperature above room temperature and below 400°C; In the first etching process, a first etching solution is used to etch the area of ​​the first surface that is not covered by the first resist pattern, thereby forming a first recess on the first surface; The process of coating the first recessed portion with resin; In the second etching process, a second etching solution is used to etch the area of ​​the second surface that is not covered by the second resist pattern, thereby forming a second recess on the second surface. The process of removing the resin; and The process of removing the first resist pattern and the second resist pattern.

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