Metal shield and its manufacturing method

Abstract

The purpose of this invention is to provide a metal shield that is not easily deformed or broken at its boundary and a method for manufacturing the same. A metal shield has an effective area, a surrounding area, and a dummy area. The effective area has a first through hole and a first vertex portion, the first vertex portion having a height H1. The surrounding area is located around the effective area. The dummy area is located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1.

Description

[Technical Field]

[0001] This invention relates to a metal shield and its manufacturing method. [Previous Technology]

[0002] The pixels of an organic EL (Electroluminescence) display device are formed by depositing the pixel material onto a substrate using a metal mask through vapor deposition. Therefore, improving the performance of the metal mask is more important for improving the image quality of an organic EL display device.

[0003] For example, Patent Document 1 discloses a method for manufacturing a metal mask capable of forming through holes with high precision. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2015-163734 [Summary of the Invention]

[0005] [The problem the invention aims to solve]

[0006] The metal mask, for example, has an effective area configured with a through hole and a surrounding area located around the effective area. Such a metal mask is disposed on a frame for pixel deposition.

[0007] Furthermore, it is known that when an effective area is formed by etching, excessive etching occurs at the boundary between the effective area and the surrounding area. If this excessive etching occurs, the thickness of the boundary between the effective area and the surrounding area will become thinner. As a result, the boundary may deform or break.

[0008] This invention was made in view of the above-mentioned problems, and its object is to provide a metal shield that is not easily deformed or broken, and a method for manufacturing the same. [Technical means to solve the problem]

[0009] A metal shield according to one embodiment of the present invention has an effective area, a surrounding area, and a dummy area. The effective area has a first through hole and a first vertex portion. The first vertex portion has a height H1. The surrounding area is located around the effective area. The dummy area is located between the effective area and the surrounding area. The dummy area has a second vertex portion. The second vertex portion has a height H2, and the height H2 is higher than the height H1.

[0010] A method for manufacturing the aforementioned metal mask according to one embodiment of the present invention includes the following steps: preparing a metal plate having a first surface and a second surface located opposite to the first surface; and an etching step, wherein the metal mask is formed by etching the metal plate; the metal mask has an effective area, a surrounding area, and a dummy area, the effective area having a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1. [Effects of the Invention]

[0011] In at least one embodiment of the present invention, a metal shield that is not easily deformed or broken at the boundary portion and a method thereof are provided.

Implementation Method

[0013] Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings. Furthermore, in the drawings accompanying this specification, sometimes the scale and aspect ratios are appropriately altered and enlarged compared to the actual object for ease of illustration and understanding.

[0014] Unless otherwise specified, in this specification and these drawings, examples of metal masks used for patterning organic materials in a desired pattern on a substrate during the manufacture of an organic EL display device and their manufacturing methods are described in one embodiment of this specification. However, this is not a limitation, and the present invention can be applied to metal masks for various purposes. For example, the metal mask of the present invention can also be used to manufacture a device for displaying or projecting images or videos used to represent virtual reality (VR) or augmented reality (AR).

[0015] Unless otherwise specified, all information in this specification and / or these drawings shall be interpreted as follows.

[0016] Terms referring to substances that form the basis of a composition may not be distinguished solely by their names. For example, terms such as "substrate," "base material," "plate," "sheet," or "film" conform to the above description.

[0017] Terms and / or values ​​referring to shape and / or geometric conditions are not necessarily strictly defined, and can be interpreted to include the range of degrees to which the same function can be expected. For example, terms such as "parallel" and / or "orthogonal" fit the above terms. Also, terms such as "value of length" and / or "value of angle" fit the above values.

[0018] When expressing that a component is located "above," "below," "on the upper side," "on the lower side," "above," or "below," it can include a state in which a component is directly connected to other components, and a state in which another component is included between a component and other components. In other words, a state in which another component is included between a component and other components can also be expressed as a state in which a component is indirectly connected to other components. Furthermore, the expressions "above," "on the upper side," or "above" can be interchanged with the expressions "below," "on the lower side," or "below." In other words, the up and down directions can also be reversed.

[0019] When the same or similar symbols are used to mark the same parts and / or parts with the same function, repeated descriptions are sometimes omitted. Also, the dimensional ratios in the drawings are sometimes different from the actual ratios. Also, sometimes a part of the components of the embodiment is omitted from the drawings.

[0020] Alternatively, one or more embodiments may be combined with one or more variations without causing contradiction. Furthermore, one or more embodiments may be combined with each other without causing contradiction. Also, one or more variations may be combined with each other without causing contradiction.

[0021] When a plurality of steps are disclosed in a manufacturing method or other method, other undisclosed steps may be performed between the disclosed steps. Furthermore, the order of steps is not limited to the extent that no contradiction arises.

[0022] The numerical range expressed by the symbols “~” and / or “-” includes the numerical values ​​before and after the symbols “~” and / or “-”. For example, the numerical range expressed as “34 to 38% of mass” is the same as the numerical range expressed as “more than 34% of mass and less than 38% of mass”.

[0023] Regarding the numerical values ​​described in this invention, the numerical range can also be defined by combining any one of the candidate values ​​of the plurality of upper limits with any one of the candidate values ​​of the plurality of lower limits. In addition, unless otherwise specifically mentioned, the numerical range can also be defined by combining any two of the candidate values ​​of the plurality of upper limits, and the numerical range can also be defined by combining any two of the candidate values ​​of the plurality of lower limits.

[0024] One embodiment of the present invention will be described in the following paragraphs and thereafter. This embodiment is one example of an embodiment of the present invention. The present invention is not to be interpreted as limited to this one embodiment.

[0025] The first embodiment of the present invention is a metal shield having an effective area, a surrounding area, and a dummy area. The effective area has a first through hole and a first vertex portion. The first vertex portion has a height H1. The surrounding area is located around the effective area. The dummy area is located between the effective area and the surrounding area. The dummy area has a second vertex portion. The second vertex portion has a height H2, and the height H2 is higher than the height H1.

[0026] The second state of the present invention is the same as the metal mask of the first state described above, wherein the dummy area may also be an area equal to the range of the second vertex portion having 2 to 5 rows.

[0027] The third state of the present invention is the same as the metal shield of the first or second state described above, wherein the height H2 of the area near the surrounding area is higher than the height H2 of the area near the effective area on the same straight line from the effective area to the surrounding area and across the dummy area.

[0028] The fourth state of the present invention is a metal shield of any of the first to third states described above, wherein the height H2 is more than 1.05 times and less than 4.00 times the height H1.

[0029] The fifth aspect of the present invention is a metal shield as described in any of the first to fourth aspects, wherein the metal shield has a first surface and a second surface located on the opposite side of the first surface. The dummy area has a second through hole. The first through hole has a first recess located on the first surface side, a second recess located on the second surface side, a first connecting portion, and a first angle θ1. The first connecting portion is an edge connecting the first recess and the second recess. The first angle θ1 is the angle formed by the straight line K1 passing through the portion P1a closest to the first vertex of the first connecting portion and the portion P2a closest to the first connecting portion of the first vertex with respect to the thickness direction N of the metal shield. The second through hole has a third recess located on the first surface side, a fourth recess located on the second surface side, a second connecting portion, and a second angle θ2. The second connecting portion is the edge connecting the third recess and the fourth recess. The second angle θ2 is the angle formed by the straight line K2 passing through the portion P1b closest to the second vertex of the second connecting portion and the portion P2b closest to the second connecting portion of the second vertex relative to the thickness direction N of the metal shield. The second angle θ2 is smaller than the first angle θ1.

[0030] The sixth embodiment of the present invention is a metal shield as described in any of the first to fifth embodiments above. Alternatively, the metal shield may have a first surface and a second surface located opposite to the first surface. The dummy area has a second through hole. The first through hole has a first recess on the first surface side, a second recess on the second surface side, a first connecting portion, and a height H3. The first connecting portion is a ridge connecting the first and second recesses. The height H3 is the height from the first surface to the first connecting portion. The second through hole has a third recess on the first surface side, a fourth recess on the second surface side, a second connecting portion, and a height H5. The second connecting portion is a ridge connecting the third and fourth recesses. The height H5 is the height from the first surface to the second connecting part, and the height H5 is greater than the height H3.

[0031] The seventh aspect of the present invention is a metal shield of any of the first to sixth aspects described above, wherein the first through hole has a height H3 and a height H4, the height H3 is the height from the first surface to the first connecting portion, the height H4 is the height from the second surface to the first connecting portion, and the height H3 is shallower than the height H4.

[0032] The eighth state of the present invention is a metal mask of any of the states 1 to 7 described above, wherein the dummy area may also have a vertex portion that has not been etched and remains.

[0033] The ninth aspect of the present invention is a method for manufacturing a metal mask, which includes the following steps: preparing a metal plate having a first surface and a second surface located on the opposite side of the first surface; and an etching step, which is to form the metal mask by etching the metal plate; the metal mask has an effective area, a surrounding area, and a dummy area, the effective area having a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1.

[0034] First, an example of a vapor deposition apparatus equipped with a metal mask will be described with reference to FIGS. 1 and 2. Here, FIG. 1 is a top view of a metal mask apparatus 10 equipped with a metal mask 20 according to an embodiment of the present invention, viewed from the first surface 20a side of the metal mask 20, and FIG. 2 is a cross-sectional view of the vapor deposition apparatus.

[0035] As shown in FIG. 1, each metal mask 20 may have a generally rectangular shape extending in one direction. Furthermore, the metal mask device 10 may include a plurality of metal masks 20 comprising a generally rectangular metal plate, and a frame 15 mounted on the periphery of the plurality of metal masks 20. Moreover, the plurality of metal masks 20 may be arranged along the width direction intersecting the length direction of the metal masks 20. Additionally, each metal mask 20 may be fixed to the frame 15 at both ends in the length direction of the metal mask 20 by, for example, welding.

[0036] The metal shield device 10 may include a component fixed to the frame 15 and partially overlapping the metal shield 20 in the thickness direction. Examples of such components are not particularly limited, such as components that extend in a direction intersecting the length direction of the metal shield 20 and support the metal shield 20, and components that overlap the gap between two adjacent metal shields.

[0037] As shown in FIG. 2, the metal mask device 10 is supported in the vapor deposition apparatus 90 in a manner opposite to the substrate 92. Here, the substrate 92 is the object to be vapor deposited on the metal mask 20, such as a glass substrate. When the metal mask device 10 is housed in the vapor deposition apparatus 90 as shown in FIG. 2, the surface of the metal mask 20 opposite to the substrate 92 is referred to as the first surface 20a, and the surface of the metal mask 20 located on the side of the crucible 94 holding the vapor deposition material 98 is referred to as the second surface 20b.

[0038] A metal shield 20 is disposed on the crucible 94 side of the substrate 92 within the vapor deposition apparatus 90. Here, the metal shield 20 and the substrate 92 can also be tightly bonded by magnetic force.

[0039] Alternatively, a crucible 94 for containing the vapor deposition material 98 and a heater 96 for heating the crucible 94 may be disposed below the metal mask device 10 within the vapor deposition apparatus 90. Here, as an example, the vapor deposition material 98 may be an organic light-emitting material. The vapor deposition material 98 in the crucible 94 is vaporized or sublimated by heating from the heater 96. The vaporized or sublimated vapor deposition material 98 is attached to the substrate 92 through the first through hole 25a of the metal mask 20. In this way, the vapor deposition material 98 is formed on the surface of the substrate 92 with a desired pattern corresponding to the position of the first through hole 25a of the metal mask 20.

[0040] When it is desired to deposit different types of vapor deposition materials according to RGB pixels, different metal masks 20 can be used according to the color of the organic light-emitting material to deposit the vapor deposition material 98 on the surface of the substrate 92. For example, organic light-emitting materials for red, green and blue can be deposited sequentially on the substrate 92. Alternatively, the metal mask 20 (metal mask device 10) can be moved relative to the substrate 92 little by little along the arrangement direction of the first through hole 25a (one of the above directions) to deposit the organic light-emitting materials for red, green and blue in sequence.

[0041] Furthermore, the frame 15 of the metal shield device 10 can also be installed on the periphery of the rectangular metal shield 20. The frame 15 holds the metal shield 20 in a stretched state. The metal shield 20 and the frame 15 can also be fixed to each other, for example, by spot welding.

[0042] Figure 1 shows an example in which a plurality of long strip metal shields 20 are provided on the frame 15. Alternatively, a large sheet metal shield 20 with a shape substantially the same as the frame 15 may also be provided on the frame 15.

[0043] Hereinafter, the metal mask of the present invention will be described in detail using a metal mask for vapor deposition of organic light-emitting materials for organic EL display devices as an example. However, the application of the metal mask of the present invention is not limited to vapor deposition of organic light-emitting materials for organic EL display devices. In addition, it can also be used to manufacture devices for displaying or projecting images or videos used to represent virtual reality (VR) or augmented reality (AR).

[0044] The metal shield of the present invention has an effective area, a surrounding area, and a dummy area. The effective area has a first through hole and a first vertex portion. The first vertex portion has a first height R1. The surrounding area is located around the effective area. The dummy area is located between the effective area and the surrounding area. The dummy area has a second vertex portion. The second vertex portion has a second height R1, and the second height R1 is higher than the first height R1.

[0045] FIG3 shows a top view of a metal mask 20 according to one embodiment of the present invention. The metal mask 20 can also be obtained by etching a first through hole 25a into a metal plate 51. As shown in FIG3, the metal mask 20 has an effective area 22 with the first through hole 25a disposed therein, a surrounding area 23 located around the effective area 22, and a dummy area 24 located at least a portion of the boundary between the effective area 22 and the surrounding area 23. The metal mask 20 may have a generally rectangular outline when viewed from above.

[0046] The height T from the first surface to the second surface is preferably 50 μm or less, or it can be 40 μm or less, or 35 μm or less, or 30 μm or less, or 25 μm or less, or 20 μm or less, or 18 μm or less, or 15 μm or less, or 13 μm or less. By reducing the height T, it is possible to suppress the adhesion of the vapor-deposited material 98 to the second wall surface 36a of the second recess 35a during the vapor deposition step. Furthermore, this phenomenon, in which the adhesion of the vapor-deposited material to the substrate is hindered by the wall surface of the through hole, is also called shading.

[0047] Furthermore, the height T is preferably 2 μm or more, and may also be 5 μm or more, 10 μm or more, or 15 μm or more. By increasing the height T, there is a tendency to further improve the strength of the metal shield 20. In this way, deformation or breakage of, for example, the effective area 22 can be suppressed.

[0048] Furthermore, the range of height T can also be defined by a combination of any one of the above-mentioned candidate values ​​of the plurality of lower limits and any one of the above-mentioned candidate values ​​of the plurality of upper limits. Also, height T is the thickness of the portion of the metal shield 20 where the first recess 30a and the second recess 35a are not formed. In other words, height T can also be a thickness equal to the thickness of the surrounding area 23 or the thickness of the metal plate 51 of the metal shield 20.

[0049] Preferably, the coefficient of thermal expansion of the metal mask 20 is the same as that of the frame 15 or the substrate 92. This suppresses positional shifts caused by dimensional differences in the metal mask 20, frame 15, and substrate 92 during vapor deposition processes performed at high temperatures. Therefore, it suppresses the reduction in dimensional or positional accuracy of the vapor-deposited material 98 attached to the substrate 92 due to positional shifts.

[0050] For example, when a glass substrate is used as the substrate 92, a nickel-containing iron alloy can be used as the main material for the metal mask 20 and the frame 15. Examples of nickel-containing iron alloys include iron alloys containing 30% to 54% by mass of nickel. More specifically, examples of such iron alloys include Invar alloys containing 34% to 38% by mass of nickel, super Invar alloys containing cobalt in addition to 30% to 34% by mass of nickel, and low thermal expansion Fe-Ni plating alloys containing 48% to 54% by mass of nickel.

[0051] Furthermore, when the temperatures of the metal mask 20, frame 15, and substrate 92 do not reach high temperatures during the vapor deposition process, it is not particularly necessary to set the coefficients of thermal expansion of the metal mask 20 and frame 15 to be the same as those of the substrate 92. In this case, in addition to the nickel-containing iron alloys mentioned above, other materials that can be used for the metal plate 51 constituting the metal mask 20 include chromium-containing iron alloys such as stainless steel, nickel, or nickel-cobalt alloys.

[0052] The metal mask 20 may have a plurality of effective areas 22. For example, as shown in FIG3, the metal mask 20 may have a plurality of effective areas 22 arranged in a row at specific intervals along a direction parallel to the length direction. Such a metal mask 20 is sometimes also referred to as a so-called rod-shaped metal mask. In this case, as shown in FIG1, the metal mask device 10 may have a plurality of metal masks 20 arranged in a width direction orthogonal to its length direction and mounted on the frame 15.

[0053] Furthermore, as another example, the metal shield 20 may also have a plurality of effective regions 22 arranged at specific intervals along a direction parallel to one side of the metal shield 20, and a plurality of effective regions 22 arranged at specific intervals along another direction orthogonal to the aforementioned direction. In other words, the metal shield 20 may also have a plurality of effective regions 22. In this case, the metal shield device 10 may also mount a metal shield 20 that is close in size to the frame 15.

[0054] The effective region 22 has a first through hole 25a and a first vertex portion 32a. The effective region 22 may have a plurality of first through holes 25a and a plurality of first vertex portions 32a. Here, the first vertex portion 32a refers to the portion that has the maximum height on the plane. The first vertex portion 32a may also be formed on the side of the second surface 20b. The effective region 22 may also be a region that is opposite to the region on the substrate 92 on which the pixel is formed by vapor deposition of organic light-emitting material, and functions as a mask during vapor deposition.

[0055] An effective area 22 may also be configured to correspond to the display area of ​​an organic EL display device 100. By using this metal mask device 10, multi-sided vapor deposition of the organic EL display device can be performed. Furthermore, an effective area 22 may also be configured to correspond to the display areas of a plurality of organic EL display devices.

[0056] The effective area 22 may have a roughly rectangular outline when viewed from above. Furthermore, the effective area 22 may also have an outline of various shapes, such as a circle, depending on the shape of the display area of ​​the substrate 92.

[0057] FIG4A shows a perspective view of the effective region 22 as an embodiment of the present invention, viewed from the second surface 20b side. The effective region 22 may have a first through hole 25a formed by etching. As shown in FIG4A, the plurality of first through holes 25a formed in each effective region 22 are arranged in a specific pattern. For example, when viewed from the second surface 20b side, the first through holes 25a may be arranged with a specific spacing along the intersecting first direction D1 and second direction D2. Furthermore, the first through holes 25a may also be surrounded by a plurality of edges 33a including a plurality of first apex portions 32a. Adjacent second recesses 35a may also be connected by edges 33a.

[0058] As shown in Figure 4A, the ridge line 33a refers to the boundary formed by the meeting of the second wall surface 36a of the adjacent second recess 35a. The height of the ridge line 33a may also be variable, like a wave. Furthermore, the height of the ridge line 33a can also be referred to as the position of the ridge line 33a in the thickness direction of the metal shield 20. Generally, the height of the ridge line 33a varies depending on the distance from the center of the first through hole 25a, and the greater the distance, the higher the ridge line 33a.

[0059] Furthermore, the first vertex portion 32a refers to the portion of the edge line 33a that becomes the maximum value of height. In the case of Figure 4A, the first vertex portion 32a is surrounded by four first through holes 25a. The first vertex portion 32a is located in the edge line at a position relatively far from the center of the first through holes 25a.

[0060] The lower the height H1 of the first vertex portion 32a, the easier it is for the first angle θ1 to increase. If the first angle θ1 is larger, the utilization efficiency or deposition accuracy of the vapor-deposited material 98 is easier to improve. According to this viewpoint, it is preferable that the height H1 of the effective region 22 is relatively low.

[0061] The surrounding region 23 is the region surrounding the effective region 22, configured to surround the effective region 22. The surrounding region 23 supports the effective region 22 by being located around it. The surrounding region 23 does not have a first through hole 25a for the vapor deposition material to pass through. However, for various purposes, through holes not provided for the passage of vapor deposition material or recesses formed by semi-etching or the like may also be formed in the surrounding region 23.

[0062] The surrounding area may have the ends of the metal shield fixed to the frame. As shown in FIG1, when the metal shield 20 is a long, rod-shaped piece, the ends 17 may be located at both ends in the length direction. Furthermore, the ends 17 may also have U-shaped cuts, etc. On the other hand, when the metal shield is a large sheet with a shape roughly the same as the frame, the ends may also be located at the periphery of the metal shield. Furthermore, the ends may also be those that are partially cut off after the metal shield is fixed to the frame.

[0063] In one embodiment of the present invention, the end portion 17 may be integrally formed with the surrounding area 23 as shown in FIG3, or it may be formed by a component separate from the surrounding area. In this case, the end portion may also be joined to other parts of the surrounding area by means of welding, for example.

[0064] The dummy region 24 is the region located between the effective region 22 and the surrounding region 23. As shown in FIG3, the dummy region 24 may be located in the entire region between the effective region 22 and the surrounding region 23. Alternatively, as shown in FIG5A or FIG5B, the dummy region 24 may be located on at least one side of the generally rectangular effective region 22 and the surrounding region 23. For example, as shown in FIG5A, the dummy region 24 may also be located on two opposing sides of the boundary between the generally rectangular effective region 22 and the surrounding region 23. Furthermore, as shown in FIG5B, one or more dummy regions 24 may be formed on one side of the boundary between the generally rectangular effective region 22 and the surrounding region 23.

[0065] Furthermore, when the metal shield 20 is rod-shaped as shown in Figure 3, the dummy region 24 can be located on the side parallel to the length direction at the boundary between the effective region 22 and the surrounding region 23, or it can be located on the side parallel to the direction orthogonal to the length direction as shown in Figure 5A. By having the dummy region 24 located on the side parallel to the direction orthogonal to the length direction, deformation or breakage can be easily suppressed when the metal shield 20 is placed on the frame 15.

[0066] The dummy region 24 has a second vertex portion 32b. Here, the second vertex portion 32b refers to the portion that becomes the maximum value of height on the plane. This maximum value may also include the portion that has not been etched and remains. The second vertex portion 32b may also be formed on the side of the second surface 20b. Furthermore, the dummy region 24 may also have a second through hole 25b.

[0067] In one embodiment of the present invention, the height H2 of the second vertex portion 32b is higher than the height H1. This ensures the strength of the metal shield 20 in the area between the effective area 22 and the surrounding area 23, thereby suppressing deformation or breakage.

[0068] When attempting to form an effective region 22 on a metal plate 51 through etching, there is a tendency to over-etch between the effective region 22 and the surrounding region 23. The area between the effective region 22 and the surrounding region 23 can also be considered the boundary between the area with the resist pattern and the area without the pattern. If over-etching occurs, the metal mask 20 will become locally thinner and the bonding strength will decrease in the area between the effective region 22 and the surrounding region 23. As a result, the metal mask 20 is prone to deformation or the effective region 22 is prone to breakage from the surrounding region 23.

[0069] Therefore, in one embodiment of the present invention, the height H2 of the second vertex portion 32b of the dummy region 24 is configured to be greater than the height H1 of the first vertex portion 32a of the effective region 22. This ensures the strength of the metal shield 20 in the region between the effective region 22 and the surrounding region 23, thereby suppressing deformation or breakage.

[0070] The extent of the dummy region 24 located between the effective region 22 and the surrounding region 23 can also be represented by the number of rows of the second vertex portion 32b. For example, the dummy region 24 can be an area equal to the extent of the second vertex portion 32b having one or more rows counted from the side of the surrounding region 23, an area equal to the extent of the second vertex portion having two or more rows, or an area equal to the extent of the second vertex portion 32b having three or more rows. Furthermore, the dummy region 24 can be an area equal to the extent of the second vertex portion 32b having 100 or fewer rows counted from the side of the surrounding region 23, an area equal to the extent of the second vertex portion 32b having 50 or fewer rows, an area equal to the extent of the second vertex portion having 10 or fewer rows, or an area equal to the extent of the second vertex portion having five or fewer rows. The extent of the virtual region can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits for the number of rows of the second vertex portion 32b and any one of the candidate values ​​of the plurality of upper limits. The plurality of rows of the second vertex portion 32b can also extend approximately parallel to the boundaries of the effective region 22 and the surrounding region 23.

[0071] For example, Figure 6 shows a configuration where two rows of the second vertex portions 32b are arranged in direction D1 and one row of the second vertex portions 32b are arranged in direction D2. Furthermore, as described above, the extent of the dummy region 24 can also be an area equal to the extent of a region with one or more rows of second vertex portions 32b. Here, "equal area," for example in Figure 6, refers to an area having an extent equal to the extent of a region with one row of second vertex portions 32b arranged in direction D2.

[0072] The dummy region 24 may have a second through hole 25b. Furthermore, the dummy region 24 is different from the effective region 22. Even if the vapor-deposited material is attached to the substrate 92 through the second through hole 25b present in the dummy region 24, the vapor-deposited material may not be used as a light-emitting element of the display device.

[0073] FIG4B shows a perspective view of the dummy region 24 as an embodiment of the present invention, viewed from the second surface 20b side. As shown in FIG4B, a plurality of second through holes 25b are arranged in the dummy region 24 in a pattern similar to that of the effective region 22. In the dummy region 24, the second through holes 25b can also be surrounded by a plurality of second vertices 32b and a plurality of edges 33b. Furthermore, adjacent second vertices 32b can also be connected by edges 33b.

[0074] The second vertex portion 32b, as shown in Figure 4B, refers to the portion that represents the maximum height when viewed from above, or the portion that remains unetched. In the case of Figure 4B, the second vertex portion 32b is surrounded by four second through holes 25b, and the second vertex portion 32b is located at a position relatively far from the center of each second through hole 25b.

[0075] Furthermore, as shown in Figure 4B, the ridge line 33b refers to the boundary formed by the meeting of the fourth wall surface 36b of the adjacent fourth recess 35b. The height of the ridge line 33b may also be variable, like a wave. Alternatively, the height of the ridge line 33b can be described as the position of the ridge line 33b in the thickness direction of the metal shield. Generally, the height of the ridge line 33b varies depending on the distance from the center of the second through hole 25b; the longer the distance, the higher the ridge line 33b.

[0076] The higher the height H2 of the second vertex portion 32b, the stronger the connection between the effective area 22 and the surrounding area 23 is, thus suppressing deformation or breakage.

[0077] An example of the second through hole 25b having the effective area 22 and the dummy area 24 will be described in more detail with reference to Figures 6 to 9. Figure 6 is a partial top view of the effective area 22, surrounding area 23, and dummy area 24 of the metal shield 20 as viewed from the second surface 20b side. Also, Figure 7 is a cross-sectional view along line IV-IV of Figure 6, Figure 8 is a cross-sectional view along line VV of Figure 6, and Figure 9 is a cross-sectional view along line VI-VI of Figure 6.

[0078] Specifically, Figures 7 and 8 are cross-sectional views showing the effective area 22, surrounding area 23, and dummy area 24 of the metal shield 20 cut off in the direction of the ridge line 33a between the first through holes 25a and the ridge line 33b between the second through holes 25b. Figure 9 is a cross-sectional view showing the effective area 22, surrounding area 23, and dummy area 24 of the metal shield 20 cut off in the direction of the first vertex portion 32a between the first through holes 25a and the second vertex portion 32b between the second through holes 25b.

[0079] As shown in FIG6, at least a portion of the first through hole 25a and the second through hole 25b are arranged at specific intervals along the intersecting first direction D1 and second direction D2, respectively. The first direction D1 and the second direction D2 may be aligned with the length direction or the width direction of the metal mask 20, or they may be inclined relative to the length direction or the width direction of the metal mask 20. For example, the first direction D1 may also be inclined at 45 degrees relative to the length direction of the metal mask 20.

[0080] There is no particular limitation on the distance between the first through hole 25a in the effective area 22 and the second through hole 25b in the dummy area 24. For example, when the metal cover 20 is used to manufacture a display (approximately 2 inches to 5 inches) for mobile phones or digital cameras, the distance between the first through hole 25a and the second through hole 25b may be approximately 28 μm to 254 μm in each of the first direction D1 and the second direction D2.

[0081] The first through hole 25a extends through the thickness direction of the metal mask 20. As shown in Figures 6 to 9, the first through hole 25a can also be formed by connecting the first recess 30a formed on the first surface 20a side and the second recess 35a formed on the second surface 20b side. The etching of the metal plate 51 can be performed isotropically from the hole of the resist pattern in various directions. Therefore, it becomes such that the cross-sectional area of ​​the first recess 30a or the second recess 35a at each position along the thickness direction of the metal mask 20 gradually decreases as it advances from the surface along the thickness direction.

[0082] The first through hole 25a may have a first connecting portion 41a, a first angle θ1, and a height H3. Here, the first connecting portion 41a is the edge connecting the first recess 30a and the second recess 35a. At the first connecting portion 41a, the direction of the wall expansion of the first through hole 25a changes discontinuously. In one embodiment of the present invention, at the first connecting portion 41a, the opening area of ​​the first through hole 25a viewed from above can be minimized. Also, the opening area of ​​the first through hole 25a can be minimized at a position in the thickness direction of the metal shield 20 other than the first connecting portion 41a.

[0083] Furthermore, the first angle θ1 is the angle formed by the straight line K1 relative to the thickness direction N of the metal shield. Here, the straight line K1 is a straight line passing through the portion P1a closest to the first vertex 32a in the first connecting portion 41a and the portion P2a closest to the first connecting portion 41a in the first vertex 32a. Furthermore, the height H3 is the height from the first surface 20a to the first connecting portion 41a.

[0084] Furthermore, the first recess 30a and the second recess 35a can also be distinguished by their depths. For example, as shown in FIG7, the first through hole 25a may have a first recess 30a with a height H3 and a second recess 35a with a height H4. Here, the height H3 is the height from the first surface 20a to the first connecting portion 41a. Also, the height H4 is the height from the second surface 20b to the first connecting portion 41a. In this case, the height H3 is preferably lower than the height H4. It is also possible to designate the surface having the first recess 30a at this depth relationship as the first surface 20a and the surface having the second recess 35a as the second surface 20b.

[0085] The ratio of height H3 to height H4 (H4 / H3) is preferably 1.5 or higher, or it can be 2.0 or higher, or it can be 3.0 or higher.

[0086] By increasing the ratio (H4 / H3) as described above, there is a tendency to further improve the utilization efficiency or deposition accuracy of the vapor-deposited material. Furthermore, by decreasing the ratio (H4 / H3), there is a tendency to suppress deformation or breakage in the effective region 22. Moreover, the range of the ratio (H4 / H3) can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits and any one of the candidate values ​​of the plurality of upper limits described above.

[0087] The depth relationship between the first recess 30a and the second recess 35a can also be replaced by the size of the openings of the first recess 30a and the second recess 35a. For example, the opening size of the first recess 30a can also be smaller than the opening size of the second recess 35a.

[0088] On the first surface 20a side of the effective region 22, two adjacent first through holes 25a are spaced apart along the surface direction of the first surface 20a. In other words, the first surface 51a of the metal plate 51 may also remain between two adjacent first recesses 30a. Such first through holes 25a can also be formed by etching the metal plate 51 in such a way that the first surface 51a of the metal plate 51 remains between two adjacent first recesses 30a, as described in the manufacturing method below. Furthermore, the first surface 51a of the metal plate 51 corresponds to the first surface 20a of the metal mask 20.

[0089] On the second surface 20b side of the effective region 22, the second recesses 35a of the two adjacent first through holes 25a can also be connected. In other words, the second surface 51b of the metal plate 51 constituting the metal mask 20 may not remain between the two adjacent second recesses 35a. Such first through holes 25a can also be formed by etching the metal plate 51 in such a way that the second surface 51b of the metal plate 51 does not remain between the two adjacent second recesses 35a, as described in the manufacturing method below. Furthermore, the second surface 51b of the metal plate 51 corresponds to the second surface 20b of the metal mask 20.

[0090] In the effective region 22, the second surface 20b of the metal plate 51 may not remain between two adjacent second recesses 35a. Furthermore, the first surface 51a of the metal plate 51 may not remain in the entire second surface 20b of the effective region 22. In other words, the first surface 20a of the effective region 22 may also not have a vertex portion with the same thickness as the metal plate 21.

[0091] The second through hole 25b extends through the thickness direction of the metal mask 20. As shown in Figures 6 to 9, the second through hole 25b can also be formed by connecting the third recess 30b formed on the first surface 20a side and the fourth recess 35b formed on the second surface 20b side. The etching of the metal plate 51 can be carried out isotropically from the holes of the resist pattern in various directions. Therefore, it becomes such that the cross-sectional area of ​​the third recess 30b or the fourth recess 35b at each position along the thickness direction of the metal mask 20 gradually decreases as it advances from the surface along the thickness direction.

[0092] The second through hole 25b may have a second connecting portion 41b and a second angle θ2. Here, the second connecting portion 41b is the edge connecting the third recess 30b and the fourth recess 35b. At the second connecting portion 41b, the direction of the wall expansion of the second through hole 25b changes discontinuously. In one embodiment of the present invention, at the second connecting portion 41b, the opening area of ​​the second through hole 25b viewed from above can be minimized. Also, the opening area of ​​the second through hole 25b can be minimized at a position in the thickness direction of the metal shield 20 other than the second connecting portion 41b.

[0093] Furthermore, the second angle θ2 is the angle formed by the straight line K2 relative to the thickness direction N of the metal shield. Here, the straight line K2 is a straight line passing through the portion P1b closest to the second vertex 32b in the second connecting portion 41b and the portion P2b closest to the second connecting portion 41b in the second vertex 32b. Furthermore, the height H5 is the height from the first surface 20a to the second connecting portion 41b.

[0094] Furthermore, the third recess 30b and the fourth recess 35b can also be distinguished by their depths. For example, as shown in FIG7, the second through hole 25b has a third recess 30b with a height H5 and a fourth recess 35b with a height H6. Here, the height H5 is the height from the first surface 20a to the second connecting portion 41b. Also, the height H6 is the height from the second surface 20b to the second connecting portion 41b. In this case, the height H5 is preferably lower than the height H6. It is also possible to designate the surface having the third recess 30b at this depth as the first surface 20a and the surface having the fourth recess 35b as the second surface 20b.

[0095] The ratio of height H5 to height H6 (H6 / H5) is preferably 1.5 or higher, or it can be 2.0 or higher, or it can be 3.0 or higher.

[0096] By reducing the ratio (H6 / H5) as described above, it is possible to suppress the tendency of deformation or fracture in the effective region 22. Furthermore, the range of the ratio (H6 / H5) can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits and any one of the candidate values ​​of the plurality of upper limits.

[0097] The relationship between the depths of the third recess 30b and the fourth recess 35b can also be replaced by the dimensions of the openings of the third recess 30b and the fourth recess 35b. For example, the opening dimension of the third recess 30b can also be smaller than the opening dimension of the fourth recess 35b.

[0098] On the first surface 20a side of the dummy region 24, two adjacent second through holes 25b may be spaced apart along the surface direction of the first surface 20a. In other words, the first surface 51a of the metal plate 51 may also remain between two adjacent third recesses 30b. Such second through holes 25b may also be formed by etching the metal plate 51 in such a way that the first surface 51a of the metal plate 51 remains between two adjacent third recesses 30b, as described in the manufacturing method below. Furthermore, the first surface 51a of the metal plate 51 corresponds to the first surface 20a of the metal mask 20.

[0099] On the second surface 20b side of the dummy region 24, the fourth recesses 35b of the two adjacent second through holes 25b can also be connected. In other words, the second surface 51b of the metal plate 51 constituting the metal mask 20 may not remain between the two adjacent fourth recesses 35b. Such second through holes 25b can also be formed by etching the metal plate 51 in such a way that the second surface 51b of the metal plate 51 does not remain between the two adjacent fourth recesses 35b, as described in the manufacturing method below. Furthermore, the second surface 51b of the metal plate 51 corresponds to the second surface 20b of the metal mask 20.

[0100] In the dummy region 24, the second surface 20b of the metal plate 51 may also remain between two adjacent fourth recesses 35b, or the second surface 51b of the metal plate 51 may remain throughout the entire second surface 20b in the effective region 22. In other words, the second surface 20b in the effective region 22 may also have a vertex portion with the same thickness as the metal plate 21.

[0101] In the vapor deposition step using the metal mask 20, the vapor deposition material 98 is attached to the substrate 92 through the second recess 35a, whose opening area gradually decreases. A portion of the vapor deposition material 98 moves from the crucible 94 toward the substrate 92 along the thickness direction N of the substrate 92. At this time, as shown by arrow F in FIG9, a portion of the vapor deposition material 98 moves in a direction inclined relative to the thickness direction N of the substrate 92. The portion of the vapor deposition material 98 moving in the inclined direction reaches and attaches to the second wall surface 36a before reaching the substrate 92 through the through hole 25. The higher the proportion of vapor deposition material 98 attached to the second wall surface 36a, the lower the utilization efficiency of the vapor deposition material 98 in the vapor deposition step.

[0102] Regarding the utilization efficiency of the vapor-deposited material 98, it is preferable that, as shown in FIG. 7, the second wall surfaces 36 of two adjacent second recesses 35a meet on the second surface 20b side. In this way, the second wall surface 36a forming most of the first through-hole 25a is effectively inclined relative to the thickness direction of the metal mask. This effectively improves the utilization efficiency of the vapor-deposited material 98, while simultaneously enabling stable and high-precision vapor deposition according to the desired pattern.

[0103] According to this viewpoint, the height H1 of the first vertex portion 32a of the effective region 22 is preferably configured as follows. Here, the first vertex portion 32a refers to the portion whose height is maximized on the side of the second surface 20b of the effective region 22.

[0104] Preferably, the first vertex portion 32a is located in the central region 22' of the effective region 22, as shown in FIG3 or FIG5. Here, the central region 22' refers to the central part of the effective region 22. The central region 22' can also refer to the region in the effective region 22 that is at a certain distance from the surrounding region 23. There is no particular limitation on this central region 22'. For example, it can be the inner range of 150 rows or more from the surrounding region 23 toward the center of the effective region 22, or it can be the inner range of 200 rows or more, or it can be the inner range of 300 rows or more, or it can be the inner range of 500 rows or more. There is no particular limit to the upper limit of the number of through holes, as long as they are at a certain distance or more from the surrounding region 23 toward the center of the effective region 22.

[0105] The height H1 relative to the height T is preferably 0.15 times or more, or it can be 0.20 times or more, or it can be 0.25 times or more, or it can be 0.30 times or more, or it can be 0.35 times or more, or it can be 0.40 times or more, or it can be 0.45 times or more.

[0106] The height H1 is preferably 6 μm or more, but may also be 7 μm or more, 8 μm or more, 9 μm or more, or 10 μm or more. Also, the height H1 is preferably 16 μm or less, but may also be 15 μm or less, 14 μm or less, 13 μm or less, or 12 μm or less.

[0107] By setting the height H1 above the aforementioned lower limit value, deformation or breakage of the effective area 22 can be suppressed. Furthermore, by setting the height H1 below the aforementioned upper limit value, there is a tendency to further improve the utilization efficiency of the vapor-deposited material 98 or to further improve the vapor deposition accuracy. Moreover, the range of the height H1 can also be defined by a combination of any one of the aforementioned candidate values ​​of the plurality of lower limits and any one of the aforementioned candidate values ​​of the plurality of upper limits.

[0108] The height H2 of the second vertex portion 32b of the dummy region 24 is higher than the height H1 of the first vertex portion 32a of the effective region 22. As a result, the strength in the dummy region 24 is further increased, thereby suppressing deformation or breakage of the effective region 22.

[0109] Furthermore, the second vertex portion 32b of the dummy region 24 may also be an unetched vertex portion, as shown in FIG16. In other words, the second surface 51b of the metal plate 51 may remain between two adjacent fourth recesses 35b on the second surface 20b of the dummy region 24. By creating the metal mask 20 with the second vertex portion 32b remaining, the strength in the dummy region 24 is further improved, thereby suppressing deformation or breakage of the effective region 22.

[0110] The height H2 relative to the height H1 is preferably 1.05 times or more, or it can be 1.15 times or more, or it can be 1.25 times or more, or it can be 1.35 times or more, or it can be 1.45 times or more. Furthermore, the height H2 relative to the height H1 is preferably 4.25 times or less, or it can be 4.00 times or less, or it can be 3.75 times or less, or it can be 3.50 times or less, or it can be 3.25 times or less. Moreover, the range of height H2 relative to height H1 can be any combination of the above-mentioned upper and lower limits, for example, it can be 1.05 times or more and 4.25 times or less, or it can be 1.05 times or more and 4.00 times or less, or it can be 1.15 times or more and 3.75 times or less, or it can be 1.25 times or more and 3.50 times or less, or it can be 1.35 times or more and 3.25 times or less, or it can be 1.45 times or more and 3.25 times or less. When the height H2 is 1.05 times or more than the height H1, the occurrence of fractures or depressions tends to be further suppressed. Furthermore, when the height H2 is 4.00 times or less than the height H1, the occurrence of wrinkles tends to be further suppressed.

[0111] The height H2 relative to the height T is preferably 0.40 times or more, or may be 0.45 times or more, or may be 0.50 times or more, or may be 0.55 times or more, or may be 0.60 times or more. Furthermore, the height H2 relative to the height T is preferably 1.00 times or less, or may be 0.95 times or less, or may be 0.90 times or less, or may be 0.85 times or less, or may be 0.80 times or less.

[0112] The height H2 is preferably 8.0 μm or more, and may also be 10.0 μm or more, 11.0 μm or more, 12.0 μm or more, or 13.0 μm or more. Furthermore, the height H2 is preferably 32.5 μm or less, and may also be 30.0 μm or less, 27.5 μm or less, 25.0 μm or less, or 22.5 μm or less.

[0113] By increasing the height H2 as described above, deformation or breakage of the effective region 22 can be suppressed. Furthermore, the range of the height H2 can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits and any one of the candidate values ​​of the plurality of upper limits.

[0114] Furthermore, it is preferable that, along the same straight line from the effective region 22 to the surrounding region 23 and across the dummy region 24, the height H2 near the surrounding region 23 is higher than the height H2 near the effective region 22. If the height difference between the first vertex in the effective region 22 and the second vertex in the dummy region 24 is large, stress may locally concentrate in the part with the larger height difference. However, by constructing it in such a way that the height H2 in the dummy region 24 gradually increases towards the surrounding region 23, local stress concentration can be further mitigated. Therefore, deformation or fracture of the effective region 22 is further suppressed.

[0115] The method for measuring height H1 and height H2 will be explained. First, samples 20s are taken from the effective area 22 and the dummy area 24 of the metal shield 20 for measuring height H1 and height H2. Then, height H1 and height H2 can be measured by observing from the first surface 20a side using a scanning electron microscope or the like. Furthermore, here, height H1 and height H2 are heights measured along the thickness direction of the metal shield, starting from the first surface 20a. Then, height H1 and height H2 are measured for a plurality of samples 20s using the above method, and the average value is calculated. This average value is used as height H1 and height H2.

[0116] The second angle θ2 is preferably smaller than the first angle θ1. This can suppress deformation or breakage of the effective area 22, and also tends to further improve the utilization efficiency of the vapor-deposited material or the vapor deposition accuracy. The first angle θ1 can also be adjusted according to the amount of etching when the second recess 35a is formed from the second surface by etching or the like.

[0117] The second angle θ2 relative to the first angle θ1 is preferably 1.60 times or less, or 1.30 times or less, or 1.00 times or less, or 0.95 times or less, or 0.90 times or less, or 0.85 times or less. Furthermore, the second angle θ2 relative to the first angle θ1 is preferably 0.30 times or more, or 0.35 times or more, or 0.40 times or more, or 0.45 times or more, or 0.50 times or more.

[0118] The first angle θ1 is preferably 30 degrees or more, or it can be 35 degrees or more, or it can be 40 degrees or more, or it can be 45 degrees or more, or it can be 50 degrees or more. Also, the first angle θ1 is preferably 80 degrees or less, or it can be 75 degrees or less, or it can be 70 degrees or less, or it can be 65 degrees or less, or it can be 60 degrees or less.

[0119] The second angle θ2 is preferably 10 degrees or more, but may also be 15 degrees or more, 20 degrees or more, 25 degrees or more, 30 degrees or more, or 35 degrees or more. Also, the second angle θ2 is preferably 70 degrees or less, but may also be 60 degrees or less, 55 degrees or less, or 50 degrees or less.

[0120] By setting the first angle θ1 and the second angle θ2 as described above, deformation or breakage of the effective area 22 can be suppressed, and there is a tendency to further improve the utilization efficiency of the vapor-deposited material or the vapor deposition accuracy. Furthermore, the numerical range of the first angle θ1 and the second angle θ2 can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits and any one of the candidate values ​​of the plurality of upper limits.

[0121] Preferably, the height H5 is higher than the height H3. This can suppress deformation or breakage in the effective area 22, and also tends to further improve the utilization efficiency of the vapor-deposited material or the vapor deposition accuracy. The height H5 can also be adjusted, for example, by the etching amount of the first surface 20a and the second surface 20b.

[0122] The height H5 is preferably 0.90 times or more than the height H3, or it can be 1.00 times or more than the height H3, or it can be 1.10 times or more than the height H3, or it can be 1.20 times or more than the height H3.

[0123] The height H3 relative to the height H5 is preferably 0.01 times or more, or 0.05 times or more, or 0.10 times or more, or 0.15 times or more. Furthermore, the height H3 relative to the height H5 is preferably 1.10 times or less, or 1.00 times or less, or 0.95 times or less, or 0.90 times or less, or 0.85 times or less, or 0.80 times or less, or 0.75 times or less, or 0.70 times or less, or 0.65 times or less, or 0.60 times or less. Furthermore, the range of height H3 relative to height H5 can be any combination of the aforementioned upper and lower limits. For example, it can be 0.01 times or more but less than 0.95 times, or 0.05 times or more but less than 0.90 times, or 0.10 times or more but less than 0.85 times, or 0.10 times or more but less than 0.80 times, or 0.10 times or more but less than 0.75 times. By making height H5 larger relative to height H3, the tendency for fractures or depressions to occur is further suppressed.

[0124] The height H3 relative to the height H1 is preferably 0.10 times or more, or may be 0.15 times or more, or may be 0.20 times or more, or may be 0.25 times or more. Furthermore, the height H3 relative to the height H1 is preferably 0.70 times or less, or may be 0.60 times or less, or may be 0.50 times or less, or may be 0.45 times or less, or may be 0.40 times or less.

[0125] The height H3 is preferably 0.1 μm or more, and may also be 0.3 μm or more, 0.5 μm or more, 0.7 μm or more, or 1.0 μm or more. Furthermore, the height H3 is preferably 5.0 μm or less, and may also be 4.7 μm or less, 4.4 μm or less, 4.1 μm or less, 3.8 μm or less, or 3.5 μm or less.

[0126] The height H5 relative to the height H2 is preferably 0.05 times or more, or may be 0.10 times or more, or may be 0.15 times or more. Furthermore, the height H5 relative to the height H2 is preferably 0.70 times or less, or may be 0.60 times or less, or may be 0.50 times or less, or may be 0.45 times or less, or may be 0.40 times or less, or may be 0.35 times or less.

[0127] The height H5 is preferably 0.1 μm or more, but may also be 0.5 μm or more, 1.0 μm or more, 1.5 μm or more, or 2.0 μm or more. Furthermore, the height H5 is preferably 12 μm or less, but may also be 10 μm or less, 8.0 μm or less, or 6.0 μm or less.

[0128] By setting heights H3 and H5 as described above, deformation or breakage of the effective area 22 can be suppressed, and there is a tendency to further improve the utilization efficiency or deposition accuracy of the vapor-deposited material. Furthermore, the numerical ranges of heights H3 and H5 can also be defined by a combination of any one of the candidate values ​​of the plurality of lower limits and any one of the candidate values ​​of the plurality of upper limits.

[0129] A method for manufacturing a metal mask according to one embodiment of the present invention includes the following steps: preparing a metal plate 51 having a first surface 51a and a second surface 51b located on the opposite side of the first surface 51a; and an etching step, which forms a metal mask 20 by etching the metal plate 51; the metal mask 20 has an effective area 22, a surrounding area 23, and a dummy area 24, the effective area 22 having a first through hole 25a and a first vertex portion 32a, the first vertex portion 32a having a height H1, the surrounding area 23 being located around the effective area 22, the dummy area 24 being located between the effective area 22 and the surrounding area 23, the dummy area 24 having a second vertex portion 32b, the second vertex portion 32b having a height H2, and the height H2 being higher than the height H1.

[0130] A method for manufacturing a metal mask 20 according to one embodiment of the present invention will be described mainly with reference to FIGS. 10 to 16. FIG. 10 is a diagram showing a manufacturing apparatus 70 for manufacturing a metal mask 20 using a metal plate 51. First, a winding body 50 comprising a metal plate 51 wound around a shaft member 52 is prepared. Then, the metal plate 51 of the winding body 50 is wound out from the shaft member 52, and the metal plate 51 is sequentially conveyed toward the resist film forming apparatus 71, the exposure and developing apparatus 72, the etching apparatus 73, the stripping apparatus 74, and the separation apparatus 75 shown in FIG. 10. During this process, through holes 25 are formed in the metal plate 51, and then, by cutting the long strip of metal plate, a metal mask 20 composed of a single sheet of metal plate can be obtained.

[0131] Furthermore, Figure 10 shows an example of the metal plate 51 moving between devices by being conveyed in its length direction, but it is not limited to this. For example, the metal plate 51 after being coated with a resist film in the resist film forming apparatus 71 can be wound again onto the shaft member 52, and the wound metal plate 51 can be supplied to the exposure and development apparatus 72. Also, the metal plate 51 with a resist film after being exposed and developed in the exposure and development apparatus 72 can be wound again onto the shaft member 52, and the wound metal plate 51 can be supplied to the etching apparatus 73. Also, the metal plate 51 after being etched in the etching apparatus 73 can be wound again onto the shaft member 52, and the wound metal plate 51 can be supplied to the stripping apparatus 74. Alternatively, after the metal plate 51, after the resin 54 and the like have been removed in the film stripping device 74, is wound again onto the shaft member 52, the wound metal plate 51 can be supplied to the separation device 75.

[0132] The resist film forming apparatus 71 forms a resist film on the surface of the metal plate 51. The exposure and development apparatus 72 then patterns the resist film to form a resist pattern by performing exposure and development processes on the resist film. The etching apparatus 73 uses the resist pattern as a mask to etch the metal plate 51, forming the first through-hole 25a and the second through-hole 25b on the metal plate 51. The stripping apparatus 74 removes the resist pattern or the resin 54 and other components provided to protect the unetched portions of the metal plate 51 from the etching solution. The separation apparatus 75 performs a separation step, which separates the portions of the metal plate 51 in which the first through-hole 25a and the second through-hole 25b corresponding to a single metal mask 20 are formed from the metal plate 51. In this manner, the metal mask 20 can be obtained.

[0133] In one embodiment of the present invention, a plurality of effective regions 22 are formed in such a way that a plurality of metal shields 20 can be fabricated from the metal plate 51. In other words, a plurality of metal shields 20 are distributed on the metal plate 51. For example, a plurality of through holes 25 may be formed in the metal plate 51 such that a plurality of effective regions 22 are arranged in the width direction of the metal plate 51 and a plurality of effective regions 22 for the metal shields 20 are arranged in the length direction of the metal plate 51.

[0134] The following describes in detail each step of the manufacturing method of the metal shield 20.

[0135] First, a wound body 50 comprising a metal plate 51 wound around the shaft member 52 is prepared. As a method for manufacturing a metal plate 51 having the required thickness, a rolling method, a film coating method, etc., can be used.

[0136] Next, using the resist film forming apparatus 71, resist films 53a and 53b are formed on the first surface 51a and the second surface 51b of the metal plate 51 rolled out from the winding device, as shown in FIG11. The resist films 53a and 53b can also be formed, for example, by attaching a dry film containing a photosensitive resist material such as an acrylic photocurable resin to the first surface 51a and the second surface 51b of the metal plate 51. Alternatively, the resist films 53a and 53b can also be formed, for example, by coating the first surface 51a and the second surface 51b of the metal plate 51 with a coating liquid containing a photosensitive resist material and then drying the coating liquid.

[0137] The resist films 53a and 53b can be either negative or positive, but it is preferable to use the negative type.

[0138] The thickness of the resist films 53a and 53b may be, for example, 15 μm or less, or 10 μm or less, or 6 μm or less, or 4 μm or less. Furthermore, the thickness of the resist films 53a and 53b may be, for example, 1 μm or more, or 3 μm or more, or 5 μm or more, or 7 μm or more. The range of the thickness of the resist films 53a and 53b may also be defined by a combination of any one of the above-mentioned candidate values ​​for the upper limits and any one of the above-mentioned candidate values ​​for the lower limits.

[0139] Next, the resist films 53a and 53b are exposed and developed using the exposure and development apparatus 72. As shown in FIG12, a first resist pattern 53c can be formed on the first surface 51a of the metal plate 51, and a second resist pattern 53d can be formed on the second surface 51b of the metal plate 51. For example, when using a negative resist film, a glass plate that prevents light from passing through the area to be removed in the resist film can be placed on the resist film, and the resist film can be exposed through the glass plate, thereby developing the resist film.

[0140] Subsequently, an etching step is performed using an etching apparatus 73, which involves etching the metal plate 51 using the first resist pattern 53c and the second resist pattern 53d as masks, thereby forming a metal mask 20. The etching step may also include a first-side etching step and a second-side etching step.

[0141] First, as shown in FIG13, the first surface etching step is performed. In the first surface etching step, the first etching solution is used to etch the area of ​​the first surface 51a of the metal plate 51 that is not covered by the first resist pattern 53c. For example, the first etching solution is sprayed from a nozzle disposed on the side opposite to the first surface 51a of the transported metal plate 51, through the first resist pattern 53c, toward the first surface 51a of the metal plate 51. At this time, the second surface 51b of the metal plate 51 may also be covered by a film or the like that is resistant to the first etching solution.

[0142] The result of the first surface etching step is, as shown in FIG13, that the area of ​​the metal plate 51 not covered by the first resist pattern 53c is etched using the first etching solution. This forms a plurality of first recesses 30a and third recesses 30b on the first surface 51a of the metal plate 51. For example, a solution containing ferric chloride and hydrochloric acid can be used as the first etching solution.

[0143] Next, as shown in FIG. 14, a second-side etching step is performed. In the second-side etching step, the area of ​​the second side 51b of the metal plate 51 not covered by the second resist pattern 53d is etched using a second etching solution. This forms a second recess 35a and a fourth recess 35b on the second side 51b of the metal plate 51. The etching of the second side 51b is performed until the first recess 30a and the second recess 35a communicate with each other, thereby forming a first through-hole 25a. Also, at this time, the third recess 30b and the fourth recess 35b can be made to communicate with each other, thereby forming a second through-hole 25b. As the second etching solution, similar to the first etching solution described above, a solution containing, for example, ferric chloride solution and hydrochloric acid can be used. Furthermore, during the etching of the second surface 51b, as shown in FIG14, the first recess 30 can also be covered with a resin 54 that is resistant to the second etching solution.

[0144] In the second etching step, as shown in FIG15, etching can also be performed until two adjacent second recesses 35 are connected. At the location where two adjacent second recesses 35a are connected, the two adjacent second recesses 35a meet and the ridge line 33 is separated from the first resist pattern 53c. The etching produced by etching at the ridge line 33a is also performed in the thickness direction of the metal plate 51. In this way, the second resist pattern 53d is peeled off from the metal plate 51. Furthermore, the second surface 51b can also be partially retained between two adjacent second recesses 35.

[0145] In this invention, during the second surface etching step, in the effective area 22, etching can also be performed in a manner where two adjacent second recesses 35a are connected, as shown in FIG15. Furthermore, in the dummy area 24, etching can also be performed in a manner where two adjacent second recesses 35a are not connected, as shown in FIG14, or in a manner where two adjacent second recesses 35a are connected, as shown in FIG15.

[0146] This makes it easy to make the height H2 of the second vertex portion 32b of the dummy region 24 greater than the height H1 of the first vertex portion 32a of the effective region 22. Furthermore, as shown in FIG16, by adjusting the size or shape of the holes in the second resist pattern 53d, the effective region 22 and the dummy region 24 can be formed simultaneously in the second surface etching step.

[0147] Next, a method for manufacturing an organic EL display device using the metal mask 20 of this embodiment will be described with reference to FIG2. The organic EL display device may also have a substrate 92 in a laminated state and a vapor deposition layer containing vapor deposition material 98 disposed in a patterned manner. The method for manufacturing an organic EL display device includes a vapor deposition step of using the metal mask 20 to vapor deposit the vapor deposition material 98 onto a substrate such as the substrate 92.

[0148] In the vapor deposition step, firstly, the metal mask device 10 is arranged with the metal mask 20 facing the substrate. Alternatively, a magnet can be used to make the metal mask 20 tightly adhere to the substrate 92. Alternatively, the interior of the vapor deposition device 90 can be made into a vacuum environment. In this state, the vapor deposition material 98 is evaporated and flies through the metal mask 20 to the substrate 92, thereby enabling the vapor deposition material 98 to adhere to the substrate 92 in a pattern corresponding to the through holes 25 of the metal mask 20.

[0149] Furthermore, the method for manufacturing an organic EL display device may include, in addition to the vapor deposition step of depositing vapor deposition material 98 onto a substrate such as a substrate 92 using a metal mask 20, various other steps. For example, the method for manufacturing an organic EL display device may also include a step of forming a first electrode on the substrate. A vapor deposition layer is formed on the first electrode. Furthermore, the method for manufacturing an organic EL display device may also include a step of forming a second electrode on the vapor deposition layer. Furthermore, the method for manufacturing an organic EL display device may also include a sealing step of sealing the first electrode, the vapor deposition layer, and the second electrode disposed on the substrate 92.

[0150] The vapor-deposited layer formed on the substrate 92 or the like using the metal mask 20 is not limited to the light-emitting layer described above, and may also include other layers. For example, the vapor-deposited layer may also include, in sequence from the first electrode side, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. In this case, vapor deposition steps using the metal mask 20 corresponding to each layer can also be performed separately.

[0151] Furthermore, various modifications can be made to the above embodiments. Hereinafter, variations will be described with reference to the drawings as needed. In the following description and the drawings used in the following description, parts that can be constructed in the same way as the corresponding parts in the above embodiments are represented by the same symbols, and repeated descriptions are omitted. Also, when it is clear that the effects obtainable in the above embodiments can also be obtained in the variations, the description is sometimes omitted.

[0152] (Variation Example) As a first variation, the dummy region 24 may also have a non-through recess formed by half-etching or the like to replace the second through hole 25b. A perspective view of the dummy region 24 having a non-through recess 25b' is shown in FIG17.

[0153] As a second variation, the step of forming the second recess 35 may be performed before the step of forming the first recess 30, or the steps of forming the first recess 30 and forming the second recess 35 may be performed in parallel.

[0154] As a third variation, a through hole can also be formed by irradiating the first recess 30 or the second recess 35 with laser light using a laser irradiation machine, so that the light reaches the other side of the metal plate 51 from the inside of the first recess 30 or the second recess 35.

[0155] As a fourth variation, the shape of the first through hole 25a can also be a circle or an ellipse, or other polygons. Furthermore, the arrangement of the first through holes 25a can also be lattice-shaped, diamond-shaped, or any other arbitrary arrangement.

[0156] Figure 18 shows another example of the arrangement of the first through hole 25a. The arrangement shown in Figure 18 includes a first through hole 25a having a major axis 26 parallel to direction D1 and a first through hole 25a having a major axis 26 parallel to direction D2. [Example]

[0157] Hereinafter, the present invention will be described in more detail using examples and comparative examples. The present invention is not limited to the following examples.

[0158] (Example) Using the above-described method for manufacturing a metal mask, a first recess and a second recess are formed on a metal plate to manufacture a metal mask having a through hole including the first recess and the second recess.

[0159] In this metal shield, as shown in FIG3, a dummy region is formed around the effective region. At this time, the height H2 of the second vertex of the dummy region is greater than the height H1 of the first vertex of the effective region. The metal plate that becomes the raw material of the metal shield is made of Invar alloy.

[0160] (Comparative Example) The height H2 of the second vertex portion of the dummy region is made smaller than the height H1 of the first vertex portion of the effective region. Otherwise, a metal mask is obtained in the same manner as in the embodiment.

[0161] (Evaluation) From the metal mask manufacturing process until the metal mask is installed and welded to the frame, the metal mask is visually inspected for deformation or breakage, and the results are recorded in Table 1. Furthermore, wrinkles or dents are identified as deformations in the metal mask. Here, "dent" refers to a slight indentation or bending that occurs locally from the metal mask manufacturing process until the metal mask is installed and welded to the frame. Also, "breakage" refers to a local breakage of the metal mask within the effective area or at the boundary between the effective area and the surrounding area, from the metal mask manufacturing process until the metal mask is installed and welded to the frame. Such deformation or breakage occurs when the strength of the metal mask is insufficient or when stress is concentrated in a weaker area.

[0162] [Table 1] Virtual area Effective area defect Number of lines H2 H2 / T θ2 H5 H1 H1 / T θ1 H3 T θ2 / θ1 H2 / H1 H5 / H3 H3 / H5 H3 / H1 H5 / H2 unit OK [μm] - [Spend] [μm] [μm] - [Spend] [μm] [μm] - - - - - - - Example 1 3 13.1 0.66 45.0 5.5 12.0 0.60 46.2 4.7 20 0.98 1.09 1.17 0.85 0.39 0.42 none Example 2 2 14.0 0.56 41.2 4.1 11.0 0.44 47.7 3.1 25 0.86 1.27 1.32 0.76 0.28 0.29 none Example 3 2 13.5 0.54 44.0 4.4 6.9 0.28 60.4 1.9 25 0.73 1.96 2.32 0.43 0.28 0.33 none Example 4 3 25.0 0.83 24.4 3.1 8.0 0.27 59.8 2.2 30 0.41 3.13 1.41 0.71 0.28 0.12 none Example 5 3 31.1 0.78 20.3 3.9 7.9 0.20 60.0 2.1 40 0.34 3.94 1.86 0.54 0.27 0.13 none Comparative Example 1 2 8.9 0.45 52.7 2.3 10.1 0.51 49.8 2.8 20 1.06 0.88 0.82 1.22 0.28 0.26 fracture Comparative Example 2 2 9.1 0.36 52.8 3.3 8.9 0.36 56.3 3.8 25 0.94 1.02 0.87 1.15 0.43 0.36 dent Comparative Example 3 2 35.0 0.70 17.9 15.0 8.1 0.16 42.7 1.1 50 0.42 4.32 13.64 0.07 0.14 0.43 wrinkles

[0163] As shown in Table 1, the metal shield of the embodiment further enhances the strength of the boundary portion between the effective area and the surrounding area by having a specific dummy area. As a result, from the metal shield manufacturing step until the metal shield is installed and welded to the frame, no deformation or breakage was found in the metal shield.

[0164] On the other hand, it is known that in comparative examples without a specific dummy area, in addition to deformations such as dents or wrinkles, fractures also occur in the metal shield. The reason for this is believed to be that in comparative examples without a specific dummy area, there is a strength difference between the effective area and the surrounding area; therefore, stress concentrates at the boundary between the effective area and the surrounding area, resulting in deformation or fracture. However, the cause is not limited to this.

[0165] Furthermore, by having a height H2 that is 1.05 times or more than the height H1, the strength in the dummy region is further increased, thereby suppressing deformation or fracture in the effective region. Moreover, by having a height H2 that is 4.00 times or less than the height H1, there is a tendency to further suppress the generation of wrinkles by suppressing stress concentration in areas with extremely low strength.

[0166] Furthermore, by making the height H5 higher than the height H3, the strength in the dummy area is further increased, thereby suppressing deformation or fracture in the effective area. Also, by setting the height H5 below a specific value relative to the height H3, there is a tendency to further suppress stress concentration in areas of extremely low strength, thus further suppressing the formation of wrinkles. [Industrial Applicability]

[0167] The metal mask of the present invention is industrially applicable as a metal mask for manufacturing organic EL display devices, etc. [Simplified Explanation of the Diagram]

[0012] FIG1 is a diagram showing a metal mask apparatus having a metal mask according to one embodiment of the present invention. FIG2 is a cross-sectional view showing a vapor deposition apparatus according to one embodiment of the present invention. FIG3 is a top view showing a metal mask according to one embodiment of the present invention. FIG4A is a perspective view of the effective area of ​​the metal mask according to one embodiment of the present invention viewed from the second side. FIG4B is a perspective view of the dummy area of ​​the metal mask according to one embodiment of the present invention viewed from the second side. FIG5A is a top view showing the state of the dummy area of ​​the metal mask according to one embodiment of the present invention. FIG5B is a top view showing the state of the dummy area of ​​the metal mask according to one embodiment of the present invention. FIG6 is a top view of the effective area and the dummy area of ​​the metal mask according to one embodiment of the present invention viewed from the second side. FIG7 is a cross-sectional view along line IV-IV of FIG6. FIG8 is a cross-sectional view along line VV of FIG6. FIG9 is a cross-sectional view along line VI-VI of FIG6. FIG10 is a schematic diagram illustrating an example of a method for manufacturing a metal mask. Figure 11 is an example of the steps involved in forming a resist film on a metal plate. Figure 12 is an example of the steps involved in patterning the resist film. Figure 13 is an example of the first side etching step. Figure 14 is an example of the second side etching step. Figure 15 is an example of the second side etching step. Figure 16 is an example of the second side etching step. Figure 17 is a perspective view of a dummy area with non-through recesses. Figure 18 is a top view of an example of the pattern of a vapor-deposited layer in an organic EL display device.

Claims

1. A metal shield having an effective area, a surrounding area, and a dummy area, wherein the effective area has a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1, wherein on a straight line extending from the effective area toward the surrounding area and across the dummy area, the height H2 closer to the surrounding area is higher than the height H2 closer to the effective area.

2. The metal mask as claimed in claim 1, wherein the aforementioned dummy area is an area equal to the range of the aforementioned second vertex portion having 2 to 5 rows.

3. The metal shield as claimed in claim 1, wherein the height H2 is more than 1.05 times and less than 4.00 times the height H1.

4. A metal shield having an effective area, a surrounding area, and a dummy area, wherein the effective area has a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1, the metal shield having a first surface and a second surface located on the opposite side of the first surface, the dummy area having a second through hole, the first through hole having a first recess on the side of the first surface, a second recess on the side of the second surface, a first connecting portion, and a first angle θ1, the first connecting portion being an edge portion connecting the first recess and the second recess. The first angle θ1 is the angle formed by the straight line (K1) of the portion (P1a) closest to the first vertex of the first connecting portion and the portion (P2a) closest to the first connecting portion of the first vertex of the first connecting portion, relative to the thickness direction N of the metal shield. The second through hole has a third recess on the first surface side, a fourth recess on the second surface side, a second connecting portion, and a second angle θ2. The second connecting portion is the edge connecting the third recess and the fourth recess. The second angle θ2 is the angle formed by the straight line (K2) of the portion (P1b) closest to the second vertex of the second connecting portion and the portion (P2b) closest to the second connecting portion of the second vertex of the second connecting portion, relative to the thickness direction N of the metal shield, and the second angle θ2 is smaller than the first angle θ1.

5. A metal shield having an effective area, a surrounding area, and a dummy area, wherein the effective area has a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1, the metal shield having a first surface and a second surface located on the opposite side of the first surface, the dummy area having a second through hole, the first through hole having a first recess on the side of the first surface, a second recess on the side of the second surface, a first connecting portion, and a height H3, the first connecting portion being a ridge portion connecting the first recess and the second recess, and the height H3 being the height from the first surface to the first connecting portion. The second through hole has a third recess on the first surface side, a fourth recess on the second surface side, a second connecting portion, and a height H5. The second connecting portion is the edge connecting the third recess and the fourth recess. The height H5 is the height from the first surface to the second connecting portion, and the height H5 is higher than the height H3.

6. A metal shield having an effective area, a surrounding area, and a dummy area, wherein the effective area has a first through hole and a first vertex portion, the first vertex portion having a height H1, the surrounding area being located around the effective area, the dummy area being located between the effective area and the surrounding area, the dummy area having a second vertex portion, the second vertex portion having a height H2, and the height H2 being higher than the height H1, the metal shield having a first surface and a second surface located on the opposite side of the first surface, the dummy area having a second through hole, the first through hole having a first recess on the side of the first surface, a second recess on the side of the second surface, a first connecting portion, and a first angle θ1, the first connecting portion being an edge portion connecting the first recess and the second recess. The first angle θ1 is the angle formed by the straight line (K1) passing through the portion of the first connecting part closest to the first vertex (P1a) and the portion of the first vertex closest to the first connecting part (P2a), relative to the thickness direction N of the metal shield. The second through hole has a third recess on the first surface side, a fourth recess on the second surface side, a second connecting part, and a second angle θ2. The second connecting part is the edge connecting the third recess and the fourth recess. The second angle θ2 is the angle formed by the straight line (K2) passing through the portion of the second connecting part closest to the second vertex (P1b) and the portion of the second vertex closest to the second connecting part (P2b), relative to the thickness direction N of the metal shield, and the second angle θ2 is smaller than the first angle θ1. The first through hole has a height H3 and a height H4. The height H3 is the height from the first surface to the first connecting part, and the height H4 is the height from the second surface to the first connecting part, and the height H3 is lower than the height H4.

7. The metal mask of any of claims 1 to 6, wherein the aforementioned dummy area has apex portions that remain unetched.

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