Vapor deposition mask, method for manufacturing a vapor deposition mask, and method for manufacturing a display device.

Abstract

To provide a vapor deposition mask capable of suppressing deflection in a frame, and increase of the weight.SOLUTION: A vapor deposition mask includes a frame 11 having a lattice shape enclosing multiple openings 11A, and having an outer peripheral part 11B1 enclosing an area containing all the openings 11A, and multiple mask plates attached to the frame 11 so that one opening 11A is covered with one mask plate, which are multiple mask plates in which each mask plate has multiple mask holes. The frame 11 includes a surface 11S1, a rear face 11S2 facing the surface 11S1 in the thickness direction of the frame 11, and a rib 11R protruding from the surface 11S1 in the area enclosed by the outer peripheral part 11B1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vapor deposition mask, a method for manufacturing the vapor deposition mask, and a method for manufacturing a display device.

Background Art

[0002] For forming a display element included in an organic EL device, a vacuum vapor deposition method is used. When forming a display element by the vacuum vapor deposition method, a vapor deposition mask having a plurality of mask holes is used. An example of a vapor deposition mask includes a frame having a plurality of openings and a plurality of mask plates equal in number to the openings. Each mask plate includes a mask region having a plurality of mask holes and a peripheral region surrounding the mask region. The mask plate is attached to the frame in the peripheral region. The vapor deposition mask is attached to a support portion that supports the vapor deposition mask to form a mask device. When the mask device is mounted on a vapor deposition device, a vapor deposition pattern corresponding to the shape of the mask holes of the mask plate is formed on the film formation target (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Incidentally, since the frame of a deposition mask is only about a few tens of micrometers thick, the frame may bend when the mask device is mounted on the deposition apparatus. This bending of the frame reduces the accuracy of the shape and position of the deposition pattern formed on the object to be deposited, so it is desirable to suppress the bending of the frame. In this respect, it is possible to suppress the bending of the frame by increasing its thickness. However, if the object to be deposited has a rectangular shape with sides longer than 1 meter, a frame thick enough to suppress bending would be too heavy to be practical.

[0005] The present invention aims to provide a vapor deposition mask capable of suppressing bending and weight increase in the frame, a method for manufacturing a vapor deposition mask, and a method for manufacturing a display device. [Means for solving the problem]

[0006] A vapor deposition mask for solving the above problems comprises a frame having a grid shape surrounding a plurality of openings and an outer periphery surrounding a region including all of the openings, and a plurality of mask plates attached to the frame such that one of the openings is covered by one mask plate, each of the plurality of mask plates having a plurality of mask holes, wherein the frame has a first surface, a second surface facing the first surface in the thickness direction of the frame, and ribs protruding from the first surface within the region surrounded by the outer periphery.

[0007] A method for manufacturing a vapor deposition mask to solve the above problems includes preparing a frame having a grid shape surrounding a plurality of openings and an outer periphery surrounding a region containing all of the openings, and attaching a plurality of mask plates to the frame such that one of the openings is covered by one mask plate, wherein preparing the frame involves preparing a frame having a first surface, a second surface facing the first surface in the thickness direction of the frame, and ribs protruding from the first surface within the region surrounded by the outer periphery.

[0008] A method for manufacturing a display device to solve the above problems includes forming a pattern on a deposition target using a deposition mask manufactured by the above-described method for manufacturing a deposition mask. According to the above-described vapor deposition mask, method for manufacturing the vapor deposition mask, and method for manufacturing the display device, since the frame is equipped with ribs, it is possible to suppress frame deflection by increasing the rigidity of the frame with the ribs. Furthermore, compared to the case where the thickness of the frame is increased by the height of the ribs, the increase in weight of the frame is suppressed.

[0009] In the above-described vapor deposition mask, the mask plate comprises a surface attached to the second surface and a back surface facing the surface in the thickness direction of the mask plate, and the mask holes comprises a surface opening located on the surface and a back surface opening located on the back surface, and when viewed from a viewpoint facing the surface, the surface opening may be larger than the back surface opening.

[0010] According to the above-described deposition mask, the deposition mask is mounted on the deposition apparatus so that the surface opening of the mask plate faces the deposition source. With the above-described deposition mask, the ribs are located on the first surface opposite the second surface to which the mask plate is attached, so that deposition material flying towards the mask plate at an oblique direction is prevented from entering the mask plate by the ribs. As a result, blurring of the deposition pattern caused by deposition material entering at an oblique direction is suppressed in the film to be deposited.

[0011] In the above-described vapor deposition mask, the distance between the first surface and the second surface is the thickness of the frame, and the height of the ribs may be greater than the thickness of the frame. With this vapor deposition mask, it is possible to increase the rigidity of the frame compared to the case where the height of the ribs is less than the thickness of the frame.

[0012] In the above-described vapor deposition mask, when viewed from a viewpoint opposite to the first surface, the length of the rib in a direction perpendicular to the direction in which the rib extends is the width of the rib, and the height of the rib may be greater than the width of the rib.

[0013] According to the above vapor deposition mask, compared to the case where the width of the rib is greater than the height of the rib, the greater the height of the rib, the more the centroid of the frame can be positioned closer to the rib. This makes it possible to reduce the amount of deflection that occurs in the part of the frame sandwiched between the first and second surfaces.

[0014] In the above-described vapor deposition mask, the ribs may be positioned between the two openings when viewed from a viewpoint opposite to the first surface. With this vapor deposition mask, the portion of the frame where the ribs are located is sandwiched between the two openings, making it prone to bending. In this respect, with the above-described vapor deposition mask, since the ribs are located in the portion prone to bending, the effect of suppressing bending by the ribs is significantly easier to obtain.

[0015] In the above-described deposition mask, a plurality of ribs may be provided, and the plurality of ribs may be positioned on the first surface such that, when viewed from a viewpoint opposite to the first surface, they form a grid pattern surrounding at least one of the openings. With this deposition mask, it is possible to increase the rigidity of the frame around the entire circumference of the opening surrounded by the ribs, and thus it is possible to suppress deflection around the entire circumference of the opening. [Effects of the Invention]

[0016] According to the present invention, it is possible to suppress both frame deflection and weight increase. [Brief explanation of the drawing]

[0017] [Figure 1] A perspective view showing the structure of the frame of a vapor deposition mask according to one embodiment. [Figure 2] A cross-sectional view showing the structure of the frame. [Figure 3] A perspective view showing the structure of a vapor deposition mask. [Figure 4] A cross-sectional view showing the structure of the mask plate in a vapor deposition mask. [Figure 5] A process diagram illustrating the manufacturing method of a vapor deposition mask. [Figure 6]Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 7] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 8] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 9] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 10] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 11] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 12] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 13] Process diagram for explaining the manufacturing method of the vapor deposition mask. [Figure 14] Device configuration diagram schematically showing the configuration of the vapor deposition device together with the object to be vapor-deposited. [Figure 15] Graph showing the relationship between the weight and the amount of deflection in the frame. [Figure 16] Cross-sectional view showing the structure of the mask plate in the modified example.

Embodiments for Carrying Out the Invention

[0018] Referring to FIGS. 1 to 15, an embodiment of the vapor deposition mask will be described. Hereinafter, the vapor deposition mask and the test examples will be described in order.

[0019] [Vapor Deposition Mask] Referring to FIGS. 1 to 4, the vapor deposition mask will be described. Note that, for convenience of explanation, only the frame included in the vapor deposition mask is shown in FIG. 1.

[0020] As shown in Figure 1, the frame 11 has a grid structure surrounding multiple openings 11A and an outer peripheral portion 11B1 surrounding all of the openings 11A. The frame 11 comprises a surface 11S1, which is an example of a first surface, and a back surface 11S2, which is an example of a second surface. The back surface 11S2 faces the surface 11S1 in the thickness direction of the frame 11. The frame 11 has ribs 11R protruding from the surface 11S1 within the region surrounded by the outer peripheral portion 11B1. In this embodiment, the frame 11 has multiple ribs 11R, but the frame 11 only needs to have one or more ribs 11R.

[0021] Since the frame 11 is equipped with ribs 11R, the rigidity of the frame 11 can be increased by the ribs 11R, thereby suppressing the deflection of the frame 11. In addition, the increase in weight of the frame 11 is suppressed compared to the case where the thickness of the frame 11 is increased by the height of the ribs 11R.

[0022] In this embodiment, the multiple ribs 11R include ribs 11R located between two openings when viewed from a viewpoint facing the surface 11S1. Since the portion of the frame 11 where the ribs 11R are located is sandwiched between the two openings 11A, bending is likely to occur in that portion. In this respect, with the above-described vapor deposition mask, since the ribs 11R are located in the portion that is prone to bending, the effect of suppressing bending by the ribs 11R is significantly easier to obtain.

[0023] Furthermore, in this embodiment, the multiple ribs 11R are positioned on the surface 11S1 such that, when viewed from a viewpoint opposite to the surface 11S1, they form a grid pattern surrounding at least one opening 11A. This makes it possible to increase the rigidity of the entire circumference of the opening 11A surrounded by the ribs 11R within the frame 11, and thus suppress deflection around the entire circumference of the opening 11A.

[0024] In this embodiment, the frame 11 has a grid-like structure, and the outer shape of the frame 11 is rectangular. The frame 11 has a rectangular shape that extends along a plane defined by the X direction and the Y direction perpendicular to the X direction. The frame 11 comprises a frame body 11B and a plurality of ribs 11R protruding from the frame body 11B. The frame body 11B comprises the outer peripheral portion 11B1 described above and a plurality of beam portions 11B2 located within the outer peripheral portion 11B1. The outer peripheral portion 11B1 has a rectangular ring shape. The plurality of beam portions 11B2 include beam portions 11B2 having a linear shape extending along the X direction and beam portions 11B2 having a linear shape extending along the Y direction.

[0025] Each rib 11R is located on a different beam section 11B2. Therefore, the multiple ribs 11R include ribs 11R having a linear shape extending along the X direction and ribs 11R having a linear shape extending along the Y direction. Each rib 11R is located across the entire beam section 11B2 on which it is situated, and both ends of the rib 11R in the direction in which it extends are located on the outer periphery 11B1. Preferably, each rib 11R has a length that extends across the entire beam section 11B2. That is, a part of the rib 11R does not need to be located on the outer periphery 11B1.

[0026] In this embodiment, the frame 11 comprises three beam sections 11B2 aligned along the X direction and two beam sections 11B2 aligned along the Y direction. Therefore, the multiple ribs 11R include three ribs 11R aligned along the X direction and two ribs 11R aligned along the Y direction. When viewed from a viewpoint opposite the surface 11S1, the multiple ribs 11R have a grid-like structure surrounding the two openings 11A.

[0027] Figure 2 shows the cross-sectional structure of the rib 11R along a plane that is perpendicular to the surface 11S1 of the frame 11 and perpendicular to the direction in which the rib 11R extends. As shown in Figure 2, in frame 11, the distance between the surface 11S1 and the back surface 11S2 is the thickness T of frame 11. In frame 11, the amount of protrusion of rib 11R relative to surface 11S1 is the height H of rib 11R. When viewed from a viewpoint opposite to surface 11S1, the length of rib 11R in a direction perpendicular to the direction in which rib 11R extends is the width W of rib 11R. That is, for a rib 11R extending along the X direction, the length of rib 11R along the Y direction is the width W of rib 11R. Conversely, for a rib 11R extending along the Y direction, the length of rib 11R along the X direction is the width W of rib 11R.

[0028] For example, the height of the rib 11R may be greater than the thickness T of the frame 11. In this case, it is possible to increase the rigidity of the frame 11 compared to the case where the height H of the rib 11R is less than the thickness T of the frame 11. Also, for example, the height H of the rib 11R may be greater than the width W of the rib 11R. In this case, compared to the case where the width W of the rib 11R is greater than the height H of the rib 11R, it is possible to position the centroid of the frame 11 closer to the rib 11R by the amount that the height H of the rib 11R is greater. This makes it possible to reduce the amount of deflection that occurs in the frame body 11B of the frame 11.

[0029] The material used to form the frame 11 is metal. The metal may be, for example, stainless steel and iron-nickel alloy. The iron-nickel alloy may contain 36% by mass of nickel. That is, the iron-nickel alloy may be Invar. The thickness T of the frame 11 may be, for example, 1 mm or more and 10 mm or less. The height H of the rib 11R may be, for example, 10 mm or more and 200 mm or less. The width W of the rib 11R may be, for example, 1 mm or more and 10 mm or less.

[0030] Furthermore, in a group of multiple ribs 11R, the height H may be equal for all ribs 11R, or it may include a rib 11R having a first height and a rib 11R having a second height different from the first height. Also, in a group of multiple ribs 11R, the width W may be equal for all ribs 11R, or it may include a rib 11R having a first width and a rib 11R having a second width different from the first width. In addition, a rib 11R extending along the X direction may include a rib 11R having a first length in the X direction and a rib 11R having a second length different from the first length. On the other hand, a rib 11R extending along the Y direction may include a rib 11R having a first length in the Y direction and a rib 11R having a second length different from the first length.

[0031] Figure 3 shows the oblique view structure of the deposition mask as seen from a viewpoint opposite the back surface 11S2 of frame 11. As shown in Figure 3, the deposition mask 10 comprises a plurality of mask plates 12. The plurality of mask plates 12 are attached to the frame 11 such that one mask plate 12 covers one opening 11A. Each mask plate 12 has a plurality of mask holes 12H. In other words, the deposition mask 10 comprises the same number of mask plates 12 as the number of openings 11A in the frame 11. Each mask plate 12 is attached to the back surface 11S2 of the frame 11.

[0032] Each mask plate 12 comprises a mask region 12A and a peripheral region 12B. The mask region 12A has the mask holes 12H described above. The mask holes 12H are passages through which the deposition material passes when deposition is performed using the deposition mask 10. The peripheral region 12B has an annular shape surrounding the mask region 12A. No mask holes 12H are formed in the peripheral region 12B. Each mask plate 12 is attached to the frame 11 in the peripheral region 12B. As a result, the multiple mask holes 12H are located within the opening 11A. Each mask plate 12 may be bonded to the frame 11 with an adhesive. Alternatively, each mask plate 12 may be joined to the frame 11 by welding.

[0033] Figure 4 shows the cross-sectional structure of the mask plate 12, which is perpendicular to the surface 11S1 of the frame 11 and aligns with a plane in the Y direction. As shown in Figure 4, the mask plate 12 comprises a surface 12S1 attached to the back surface 11S2 of the frame 11, and a back surface 12S2 facing the surface 12S1 in the thickness direction of the mask plate 12. The mask hole 12H comprises a surface opening 12H1 located on the surface 12S1 and a back surface opening 12H2 located on the back surface 12S2. Viewed from a viewpoint facing the surface 12S1 of the mask plate 12, the surface opening 12H1 is larger than the back surface opening 12H2.

[0034] The deposition mask 10 is mounted on the deposition apparatus so that the surface opening 12H1 of the mask plate 12 faces the deposition source. With the deposition mask 10, the ribs 11R are located on the surface 11S1 facing the back surface 11S2 to which the mask plate 12 is attached. As a result, deposition material flying towards the mask plate 12 from entering the mask plate 12 at an oblique angle is suppressed by the ribs 11R. This suppresses blurring of the deposition pattern caused by deposition material entering at an oblique angle in the film to be deposited.

[0035] [Method for manufacturing vapor deposition masks] The manufacturing method of the vapor deposition mask 10 will be explained with reference to Figures 5 to 13. The method for manufacturing the deposition mask 10 includes preparing a frame 11 having a grid-like structure surrounding a plurality of openings 11A and an outer peripheral portion 11B1 surrounding the region containing all of the openings 11A, and attaching a plurality of mask plates 12 to the frame 11 so that one opening 11A is covered by one mask plate 12. Preparing the frame 11 involves preparing a frame 11 having a surface 11S1, a back surface 11S2, and ribs 11R protruding from the surface 11S1 within the region surrounded by the outer peripheral portion 11B1. The method for manufacturing the deposition mask 10 will be described in more detail below with reference to the drawings.

[0036] As shown in Figures 5 to 10, in the manufacturing method of the vapor deposition mask 10, first, a substrate 20 for forming the mask plate 12 is prepared (see Figure 5). The substrate 20 of the mask plate 12 comprises a metal plate 21 for forming the mask plate 12 and a support 22 for supporting the metal plate 21. The support 22 is formed from a resin layer 22a and a glass substrate 22b. In the substrate 20, the resin layer 22a is sandwiched between the metal plate 21 and the glass substrate 22b.

[0037] Next, the thickness of the metal plate 21 is reduced by etching from the surface 21F. For example, it is possible to reduce the thickness of the metal plate 21 to less than half the thickness of the metal plate 21 before etching (see Figure 6). Then, a resist layer PR is formed on the surface 21F of the metal plate 21 (see Figure 7). By exposure and development of the resist layer PR, a resist mask RM is formed on the surface 21F (see Figure 8).

[0038] Next, the metal plate 21 is wet-etched from the surface 21F using a resist mask RM. This creates multiple mask holes 12H in the metal plate 21 (see Figure 9). In the wet etching of the metal plate 21, a surface opening 12H1 is formed on the surface 21F, and then a smaller back surface opening 12H2 is formed on the back surface 21R. Subsequently, the resist mask RM is removed from the surface 21F to manufacture the mask plate 12 (see Figure 10). The surface 21F of the metal plate 21 corresponds to the surface 12S1 of the mask plate 12, and the back surface 21R of the metal plate 21 corresponds to the back surface 12S2 of the mask plate 12.

[0039] The process of preparing the base material 20 includes a step of sandwiching a resin layer 22a between a metal plate 21 and a glass substrate 22b, and joining the metal plate 21 and the glass substrate 22b via the resin layer 22a. When the metal plate 21, the resin layer 22a, and the glass substrate 22b are joined, first, a CB (Chemical Bonding) treatment is performed on at least the surfaces of the metal plate 21 and the glass substrate 22b that are in contact with the resin layer 22a. The surfaces of the metal plate 21 and the glass substrate 22b on which the CB treatment is performed are the target surfaces. In the CB treatment, for example, a chemical solution is applied to the target surface, thereby imparting functional groups that are reactive with the resin layer 22a to the target surface. In the CB treatment, for example, a Si-based compound is imparted to the target surface.

[0040] Then, the metal plate 21, the resin layer 22a, and the glass substrate 22b are stacked in the order described above, and then they are heat-pressed together. At this time, the target surface of the metal plate 21 and the target surface of the glass substrate 22b are brought into contact with the resin layer 22a. As a result, the functional groups attached to the target surface react with the functional groups located on the surface of the resin layer 22a, thereby bonding the metal plate 21 and the resin layer 22a, and also bonding the glass substrate 22b and the resin layer 22a. The material forming the resin layer 22a may be, for example, polyimide.

[0041] The metal sheet 21 can be manufactured by electrolysis or rolling. Polishing or annealing may be used as post-treatment for the metal sheet 21 obtained by these methods. When electrolysis is used to manufacture the metal sheet 21, the metal sheet 21 is formed on the surface of the electrode used for electrolysis. The metal sheet 21 is then released from the electrode surface. This completes the production of the metal sheet 21. When rolling is used to manufacture the metal sheet 21, the base material for manufacturing the metal sheet 21 is rolled. The rolled base material is then annealed to obtain the metal sheet 21.

[0042] In the thinning process to reduce the thickness of the metal plate 21 before forming a resist mask RM on the metal plate 21, wet etching can be used. The process of reducing the thickness of the metal plate 21 can be omitted. If the metal plate is formed from Invar, an etching solution capable of etching Invar, i.e., an acidic etching solution, can be used in the thinning process. The acidic etching solution may be, for example, a solution obtained by mixing perchloric acid, hydrochloric acid, sulfuric acid, formic acid, or acetic acid with either ferric perchlorate solution or a mixture of ferric perchlorate solution and ferric chloride solution. For etching the surface 21F, dip etching, spray etching, or spin etching can be used.

[0043] In etching to form multiple mask holes 12H in the metal plate 21, an acidic etching solution can be used as the etching solution. When the metal plate 21 is formed from Invar, any of the etching solutions that can be used in the thinning process described above can be used as the etching solution. Any of the etching methods that can be used in the thinning process can also be used for etching to form the mask holes 12H.

[0044] The process of preparing the base material 20 may include a step of thinning the metal plate 21 from one side before joining the metal plate 21, the resin layer 22a, and the glass substrate 22b to each other. By etching both the first and second sides of the metal plate 21, it is possible to adjust the residual stress of the metal plate 21 from both sides. This suppresses unevenness in the residual stress of 21 after etching compared to etching only one side. Therefore, when the mask plate 12 obtained from the metal plate 21 is joined to the frame 11, wrinkles in the mask plate 12 are suppressed.

[0045] As shown in Figures 11 to 13, a portion of the frame 11 and a portion of the mask plate 12 are joined together (see Figure 11). At this time, multiple mask plates 12 and a single frame 11 are joined together such that each mask plate 12 covers one opening 11A. Then, the glass substrate 22b is peeled off from the resin layer 22a (see Figure 12). Next, the resin layer 22a is peeled off from each mask plate 12 (see Figure 13). This gives rise to the vapor deposition mask 10 described above.

[0046] In the process of joining a part of the mask plate 12 to a part of the frame 11, the frame 11 is prepared. When forming the frame 11, metal plate members are prepared. As described above, the plate members may be made of materials such as Invar and stainless steel. When preparing the metal plate members, plate members for the frame body 11B and plate members for the ribs 11R are prepared separately. It is preferable that the forming material for the plate member for the frame body 11B is the same as the forming material used for the plate member for the ribs 11R, but different materials may be used.

[0047] Next, multiple openings 11A are formed in the plate member for the frame body 11B. The openings 11A may be formed by wet etching or by cutting with a laser beam. This forms the frame body 11B having a grid pattern. Then, ribs 11R having a predetermined shape are formed from the plate member for the ribs 11R, and the formed ribs 11R are attached to the frame body 11B. The ribs 11R may be attached to the frame body 11B by, for example, screwing, adhesive bonding, or welding.

[0048] In the process of joining a portion of the mask plate 12 to a portion of the frame 11, the surface 12S1 of the mask plate 12 is joined to the frame 11. Laser welding can be used as a method for joining the mask plate 12 to the frame 11. A laser beam L is irradiated through the glass substrate 22b and the resin layer 22a to the portion of the mask plate 12 where the joining portion 10Aa is located. At this time, intermittent joining portions are formed by intermittently irradiating the laser beam L along the edge of the opening 11A. On the other hand, continuous joining portions are formed by continuously irradiating the laser beam L along the edge of the opening 11A. As a result, the mask plate 12 is welded to the frame 11.

[0049] The process of peeling the support 22 from the mask plate 12 includes a first step and a second step. In the first step, a laser beam L having a wavelength that is transmitted by the glass substrate 22b and absorbed by the resin layer 22a is irradiated onto the interface between the resin layer 22a and the glass substrate 22b. This peels the glass substrate 22b from the resin layer 22a. In the first step, by irradiating the interface between the resin layer 22a and the glass substrate 22b with the laser beam L, the thermal energy from the laser beam L is absorbed by the resin layer 22a. This heats the resin layer 22a, thereby lowering the strength of the chemical bond between the resin layer 22a and the glass substrate 22b. Then, the glass substrate 22b is peeled off from the resin layer 22a.

[0050] In the second step, after the first step, the resin layer 22a is peeled off the mask plate 12 by dissolving it with a chemical solution LM. The chemical solution LM can be a liquid that can dissolve the material forming the resin layer 22a and does not react with the material forming the mask plate 12. For example, an alkaline solution can be used as the chemical solution LM. The alkaline solution may be, for example, an aqueous sodium hydroxide solution. In Figure 13, a spray method is shown as an example of a method for contacting the resin layer 22a with the chemical solution LM, but dip method and spin method can also be used as methods for contacting the resin layer 22a with the chemical solution LM.

[0051] [Method of manufacturing a display device] A method for manufacturing a display device will be described with reference to Figure 14. The method for manufacturing the display device includes forming a pattern on the deposition target S using the deposition mask 10 manufactured by the method for manufacturing the deposition mask 10. The process of forming the pattern will be described below with reference to the drawings, along with an example of a deposition apparatus.

[0052] As shown in Figure 14, the deposition apparatus 30 includes a deposition mask 10 and a storage tank 31 for housing the deposition target S. The storage tank 31 is configured to hold the deposition target S and the deposition mask 10 in predetermined positions within the storage tank 31. Inside the storage tank 31 are a holding section 32 for holding the deposition material Mvd and a heating section 33 for heating the deposition material Mvd. The deposition material Mvd held in the holding section 32 is, for example, an organic light-emitting material. The storage tank 31 positions the deposition target S and the deposition mask 10 such that the deposition mask 10 is positioned between the deposition target S and the holding section 32, and the deposition mask 10 and the holding section 32 face each other. The deposition mask 10 is placed inside the storage tank 31 with the back surface 12S2 of the mask plate 12 in close contact with the deposition target S.

[0053] In the pattern formation process, the deposition material Mvd is heated by the heating unit 33, causing the deposition material Mvd to vaporize or sublimate. The vaporized or sublimated deposition material Mvd passes through the mask holes 12H of the deposition mask 10 mask plate 12 and adheres to the deposition target S. As a result, for example, if the deposition material Mvd is a material for forming the organic layer of an organic EL element, an organic layer having a shape corresponding to the shape and position of the mask holes 12H of the deposition mask 10 is formed on the deposition target S. The deposition material Mvd may also be a metallic material for forming the pixel electrodes of the pixel circuit of the display layer.

[0054] [Example Test] Refer to Figure 15 to explain the test example. Below, we will explain the relationship between the frame weight and deflection obtained by simulation using analysis simulation software (Femtet, manufactured by Murata Software, Inc.) (Femtet is a registered trademark). The magnitude of the deflection described below is the maximum deflection that occurs in each frame. Deflection is the distance between the XY plane and the point on the frame furthest from the XY plane, when the back surface of the frame is positioned on the XY plane, which is the reference plane.

[0055] [Frame Thickness] For frames without ribs, the weight (kg) and deflection (mm) were calculated when the frame thickness was changed. The weight and deflection were calculated for both the first and second frames. Specifically, the first frame was designed with a grid structure where three openings were aligned in the X direction and two openings in the Y direction. The second frame was designed with a grid structure where four openings were aligned in the X direction and three openings in the Y direction.

[0056] For both the first and second frames, the weight and deflection were calculated when the frame thickness was set to 1 mm, 3 mm, 5 mm, 7 mm, 10 mm, 15 mm, 30 mm, 50 mm, and 100 mm. The calculation results for each frame are shown in Figure 15. In Figure 15, the calculation results for the first frame are shown by black circles, and the calculation results for the second frame are shown by white circles.

[0057] Furthermore, the forming material for the first and second frames was set to an iron-nickel alloy containing 36 mass% nickel, i.e., Invar. Therefore, when calculating the weight and deflection, the Young's modulus was set to 140 GPa, the Poisson's ratio to 0.22, and the density to 8 g / cm³. 3 The settings were adjusted as follows. Additionally, the dimensions of each part in the first and second frames were set as follows. The size of the openings in each frame was set to match the size of a 21-inch PC monitor with a 4:3 aspect ratio.

[0058] [First frame] • External dimensions: Length in the X direction 1700mm • Outer dimensions: Length in the Y direction 1100mm • Opening: Length in the X direction 471.0 mm • Opening: Length in the Y direction 355.0 mm • Distance between apertures in the X direction: 18.5 mm • Distance between openings in the Y direction: 165.0 mm

[0059] [Frame 2] • External dimensions: Length in the X direction 2360mm • Outer dimensions: Length in the Y direction 1430mm • Opening: Length in the X direction 471.0 mm • Opening: Length in the Y direction 355.0 mm • Distance between apertures in the X direction: 75.3 mm • Distance between openings in the Y direction: 70.0 mm

[0060] As shown in Figure 15, it was observed that the amount of deflection of the frame tends to decrease as the weight of the frame increases. However, in the case of a frame without ribs, for example, in order to achieve a deflection of 0.01 mm or less, it was found that the first frame needed to weigh about 700 kg and the second frame needed to weigh 1000 kg or more. Thus, in the case of a frame without ribs, it was found that an excessive weight is required for the vapor deposition mask in order to suppress the amount of frame deflection to a range that is practically preferable for the vapor deposition mask.

[0061] [Number of ribs] For each of the first and second frames, the weight and deflection were calculated when the number of ribs aligned along the X direction and the number of ribs aligned along the Y direction were changed. In this calculation, the thickness of each frame was set to 7 mm, the rib height to 30 mm, and the rib width to 7 mm. The results of the weight and deflection calculations are shown in Table 1.

[0062] Note that in Table 1, Test Examples 1-1 to 1-3 are test examples for the first frame. On the other hand, in Table 1, Test Examples 1-4 to 1-6 are test examples for the second frame. Furthermore, the frames of Test Examples 1-2 and 1-5 have ribs extending along the beam section but no ribs extending along the outer perimeter. In contrast, the frames of Test Examples 1-3 and 1-6 have both ribs extending along the beam section and ribs extending along the outer perimeter.

[0063] [Table 1]

[0064] As is clear from comparing the calculation results in Test Examples 1-1 to 1-3, in the first frame, it was observed that increasing the number of ribs reduced the amount of deflection in the frame. Similarly, in the second frame, as is clear from comparing the calculation results in Test Examples 1-4 to 1-6, it was observed that increasing the number of ribs reduced the amount of deflection in the frame.

[0065] Furthermore, as is clear from Figure 15 and Table 1, the first frame was found to be lighter than the first frame without ribs and with a thickness of 30 mm, even when equipped with ribs. Also, as is clear from Figure 15 and Table 1, the second frame was found to be lighter than the second frame without ribs and with a thickness of 30 mm, even when equipped with ribs.

[0066] [Rib width] For both the first and second frames, the weight and deflection were calculated when the width of each rib was changed. The number of ribs in each frame was set to the same number as in Test Example 1-3 for the first frame, and to the same number as in Test Example 1-6 for the second frame. The thickness of each frame was set to 7 mm, and the rib height was set to 30 mm. The results of the weight and deflection calculations are shown in Table 2.

[0067] Note that in Table 2, Test Examples 2-1 to 2-6 are test examples for the first frame. On the other hand, in Table 2, Test Examples 2-7 to 2-15 are test examples for the second frame.

[0068] [Table 2]

[0069] As is clear from comparing the calculation results in Test Examples 2-1 to 2-6, in the first frame, it was observed that the amount of deflection in the frame decreased as the width of the ribs increased. Also, as is clear from comparing the calculation results in Test Examples 2-7 to 2-15, in the second frame, when the width of the ribs was 30 mm or less, it was observed that the amount of deflection in the frame decreased as the width of the ribs increased. In contrast, when the width of the ribs was 50 mm or more, it was observed that the amount of deflection in the frame increased compared to when the frame width was 30 mm.

[0070] As is clear from Figure 15 and Table 2, the first frame with ribs was found to be lighter than the first frame without ribs and with a thickness of 30 mm. Also, as is clear from Figure 15 and Table 2, in the range where the rib width is 50 mm or less, the second frame with ribs was found to be lighter than the second frame without ribs and with a thickness of 30 mm. In contrast, as is clear from Figure 15 and Table 2, when the rib width is 70 mm, the second frame with ribs was found to have the same weight as the second frame without ribs and with a thickness of 30 mm.

[0071] [Rib height] For both the first and second frames, the weight and deflection were calculated when the height of each rib was changed. The number of ribs in each frame was set to the same number as in Test Example 1-3 for the first frame, and to the same number as in Test Example 1-6 for the second frame. The thickness of each frame was set to 7 mm, and the width of the ribs was set to 10 mm. The results of the weight and deflection calculations are shown in Table 3.

[0072] Note that in Table 3, Test Examples 3-1 to 3-6 are test examples for the first frame. On the other hand, in Table 3, Test Examples 3-7 to 3-12 are test examples for the second frame.

[0073] [Table 3]

[0074] As is clear from comparing the calculation results in Test Examples 3-1 to 3-6, in the first frame, it was observed that the amount of deflection in the frame decreased as the rib height increased. Furthermore, as is clear from comparing the calculation results in Test Examples 3-7 to 3-12, in the second frame, it was observed that the amount of deflection in the frame decreased as the rib height increased.

[0075] Furthermore, as is clear from Figure 15 and Table 3, when the rib height is 100 mm or less, the first frame with ribs was found to be lighter than the first frame without ribs and with the same thickness as the ribs. Also, as is clear from Figure 15 and Table 3, when the rib height is 100 mm or less, the second frame with ribs was found to be lighter than the second frame without ribs and with the same thickness as the ribs.

[0076] Furthermore, in Test Example 3-6, the rib width was changed to several values, and the weight and deflection of the first frame were calculated. On the other hand, in Test Example 3-12, the rib width was changed to several values, and the weight and deflection of the second frame were calculated. Specifically, the thickness of each frame was set to 7 mm, and the rib height to 200 mm. The calculation results for weight and deflection are shown in Table 4. Note that Test Example 4-1, shown below, is the same frame as Test Example 3-6, and Test Example 4-6 is the same frame as Test Example 3-12.

[0077] [Table 4]

[0078] As is clear from the comparison of the calculation results in Test Examples 4-1 to 4-5, in the first frame, it was observed that the amount of deflection in the frame increased as the rib width decreased. However, in all test examples, it was observed that the amount of deflection in the frame was 10 μm or less. Furthermore, as is clear from the comparison of the calculation results in Test Examples 4-6 to 4-10, in the second frame, it was observed that the amount of deflection in the frame increased as the rib width decreased. However, as shown in the calculation results of Test Examples 4-6 and 4-7, it was observed that when the rib width was 7 mm or more, the amount of deflection in the frame was 10 μm or less. Furthermore, as shown in the calculation results of Test Examples 4-8 to 4-10, it was observed that even when the rib width was less than 7 mm, the amount of deflection in the frame could be kept to about 10 μm.

[0079] [Frame Thickness] For both the first and second frames, the weight and deflection were calculated when the frame thickness was changed. In this process, the rib conditions for the first frame were the same as those in Test Example 4-4, namely the rib height was set to 200 mm and the rib width to 3 mm, while the thickness of the first frame was changed to several values. Similarly, the rib conditions for the second frame were the same as those in Test Example 4-9, namely the rib height was set to 200 mm and the rib width to 4.5 mm, while the thickness of the second frame was changed to several values.

[0080] Note that Test Examples 5-1 to 5-5 shown below are test examples for the first frame. Test Example 5-2 is the same frame as Test Example 4-4. Also, Test Examples 5-6 to 5-12 are test examples for the second frame. Test Example 5-7 is the same frame as Test Example 4-9.

[0081] [Table 5]

[0082] As is clear from comparing the calculation results in Test Examples 5-1 to 5-5, in the first frame, it was found that the amount of deflection in the frame was minimal when the frame thickness was 7 mm. Furthermore, as is clear from comparing the calculation results in Test Examples 5-6 to 5-12, in the second frame, it was found that the amount of deflection in the frame was minimal when the frame thickness was 3 mm.

[0083] In other words, the calculation results from Test Examples 5-1 to 5-12 showed that, from the perspective of suppressing the amount of deflection in the frame, it is necessary to set the thickness of the frame to a specific value. In contrast, as mentioned above, it is possible to suppress the amount of deflection in the frame by setting multiple values ​​for the number, width, and height of the ribs provided in the frame. Therefore, by using ribs as a means of suppressing the amount of deflection in the frame, it is possible to increase the design freedom of the frame. Moreover, it is also possible to prevent the frame from becoming excessively heavy.

[0084] As described above, according to one embodiment of the vapor deposition mask, the following effects can be obtained. (1) Since the frame 11 is equipped with ribs 11R, the rigidity of the frame 11 is increased by the ribs 11R, thereby suppressing the deflection of the frame 11. In addition, the increase in weight of the frame 11 is suppressed compared to the case where the thickness of the frame 11 is increased by the height of the ribs 11R.

[0085] (2) In the frame 11, the portion where the rib 11R is located is sandwiched between two openings 11A, so the rib 11R can be located in a portion that is prone to bending. As a result, the effect of suppressing bending by the rib 11R is significantly easier to obtain.

[0086] (3) Since it is possible to increase the rigidity of the entire circumference of the opening 11A surrounded by the rib 11R of the frame 11, it is possible to suppress deflection around the entire circumference of the opening 11A.

[0087] (4) Compared to the case where the height H of the rib 11R is less than the thickness T of the frame 11, it is possible to increase the rigidity of the frame 11. (5) Compared to the case where the width W of the rib 11R is greater than the height H of the rib 11R, the greater the height H of the rib 11R, the more the centroid of the frame 11 can be positioned closer to the rib 11R. This makes it less likely for the frame body 11B of the frame 11 to bend.

[0088] The above-described embodiment can be implemented with the following modifications. [frame] As described above in the test example, the frame 11 may be provided with a rib 11R located on the outer periphery 11B1. When the rib 11R is located on the outer periphery 11B1, it is possible to further increase the rigidity of the outer periphery 11B1.

[0089] [Mask board] The mask plate 12 may have mask holes having the shape shown in Figure 16. In the example shown in Figure 16, the mask region 12A has multiple mask holes 12H. Each mask hole 12H has a large hole 12HL and a small hole 12HS. The large hole 12HL is connected to the small hole 12HS on the way from the surface 12S1 to the back surface 12S2 of the mask plate 12. The large hole 12HL has a shape that tapers along the direction from the surface 12S1 to the back surface 12S2. The small hole 12HS has a shape that tapers along the direction from the back surface 12S2 to the surface 12S1. The large hole 12HL opens to the surface 12S1, and the opening of the large hole 12HL is the surface opening 12H1. The small hole 12HS opens to the back surface 12S2, and the opening of the small hole 12HS is the back surface opening 12H2.

[0090] Furthermore, if the mask plate 12 has large holes 12HL and small holes 12HS, for example, etching is performed on the metal plate to form the small holes 12HS, and then etching is performed to form the large holes 12HL. At this time, multiple mask regions are formed on the metal plate so that multiple mask plates 12 can be formed from the metal plate. Then, multiple mask plates are formed by cutting the metal plate so that each mask plate contains one mask region.

[0091] The vapor deposition mask 10 is formed by attaching each mask plate 12 to the frame 11. At this time, each mask plate 12 may be supported by, for example, a glass support plate, and then welded to the frame 11. Alternatively, the mask plates 12 may be attached to the frame 11 with an adhesive.

[0092] Each mask plate 12 may have multiple mask regions 12A. That is, the mask plate 12 may have multiple mask regions 12A separated by a peripheral region 12B. [Explanation of Symbols]

[0093] 10… Vapor deposition mask 11...frame 11B1…Outer periphery 11R…Rib 11S1,12S1…Surface 11S2,12S2…Back side 12… Mask board 12H… Mask holes 12H1…Surface opening 12H2…back opening

Claims

1. A metal frame having a grid-like structure surrounding multiple openings and an outer periphery surrounding the region containing all of the openings, A vapor deposition mask comprising: a plurality of mask plates attached to the frame such that one of the openings is covered by one metal mask plate, each of the plurality of mask plates having a plurality of mask holes; The aforementioned frame is Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises at least one rib protruding from the first surface, Each rib includes a portion protruding from the first surface of the first beam and has a linear shape extending along the first direction, or includes a portion protruding from the second surface of the second beam and has a linear shape extending along the second direction. The mask plate comprises a surface attached to the second surface and a back surface facing the surface in the thickness direction of the mask plate. The mask hole comprises a surface opening located on the surface and a back opening located on the back surface, and when viewed from a viewpoint facing the surface, the surface opening is larger than the back opening. Vapor deposition mask.

2. A metal frame having a grid shape surrounding a plurality of openings and an outer periphery surrounding a region including all of the openings, A vapor deposition mask comprising: a plurality of mask plates attached to the frame such that one of the openings is covered by one metal mask plate, each of the plurality of mask plates having a plurality of mask holes; The aforementioned frame is Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises at least one rib protruding from the first surface, Each rib includes a portion protruding from the first surface of the first beam and has a linear shape extending along the first direction, or includes a portion protruding from the second surface of the second beam and has a linear shape extending along the second direction. The distance between the first surface and the second surface is the thickness of the frame. The height of the rib is greater than the thickness of the frame. Vapor deposition mask.

3. A metal frame having a grid-like structure surrounding a plurality of openings and an outer periphery surrounding a region including all of the openings, A vapor deposition mask comprising: a plurality of mask plates attached to the frame such that one of the openings is covered by one metal mask plate, each of the plurality of mask plates having a plurality of mask holes; The aforementioned frame is Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises a plurality of ribs protruding from the first surface, The plurality of ribs include a portion of the rib that protrudes from the first surface of the first beam and has a linear shape extending along the first direction, and a portion of the rib that protrudes from the second surface of the second beam and has a linear shape extending along the second direction. The plurality of ribs are positioned on the first surface such that, when viewed from a viewpoint opposite to the first surface, they form a grid pattern surrounding at least one of the openings. Vapor deposition mask.

4. Viewed from a viewpoint opposite to the first surface, the length of the rib in a direction perpendicular to the direction in which the rib extends is the width of the rib. The height of the rib is greater than the width of the rib. A vapor deposition mask according to any one of claims 1 to 3.

5. The rib is located between the two openings when viewed from a viewpoint opposite to the first surface. The vapor deposition mask according to claim 1 or 2.

6. Prepare a metal frame having a grid structure surrounding multiple openings and an outer periphery surrounding the area containing all of the openings, and This includes attaching a plurality of the mask plates to the frame such that one of the openings is covered by one of the metal mask plates, Preparing the aforementioned frame means Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises at least one rib protruding from the first surface, Each rib is provided, having a linear shape extending along the first direction and including a portion protruding from the first surface of the first beam, or a linear shape extending along the second direction and including a portion protruding from the second surface of the second beam, The mask plate comprises a surface attached to the second surface, a back surface facing the surface in the thickness direction of the mask plate, and a plurality of mask holes. The mask hole comprises a surface opening located on the surface and a back opening located on the back surface, and when viewed from a viewpoint facing the surface, the surface opening is larger than the back opening. A method for manufacturing a vapor deposition mask.

7. A metal frame having a grid-like structure surrounding multiple openings and an outer periphery surrounding the region containing all of the openings, and This includes attaching a plurality of the mask plates to the frame such that one of the openings is covered by one of the metal mask plates, Preparing the aforementioned frame means Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises at least one rib protruding from the first surface, Each rib is provided, having a linear shape extending along the first direction and including a portion protruding from the first surface of the first beam, or a linear shape extending along the second direction and including a portion protruding from the second surface of the second beam, The distance between the first surface and the second surface is the thickness of the frame. The height of the rib is greater than the thickness of the frame. A method for manufacturing a vapor deposition mask.

8. A metal frame having a grid-like structure surrounding multiple openings and an outer periphery surrounding the region containing all of the openings, and This includes attaching a plurality of the mask plates to the frame such that one of the openings is covered by one of the metal mask plates, Preparing the aforementioned frame means Page 1 and, A second surface facing the first surface in the thickness direction of the frame, A frame body having a grid shape comprising the outer periphery, a first beam portion located within the outer periphery and extending along a first direction, having a first surface included in the first surface, and a second beam portion located within the outer periphery and extending along a second direction intersecting the first direction, having a second surface included in the first surface, It comprises a plurality of ribs protruding from the first surface, The frame is prepared such that the plurality of ribs include portions that protrude from the first surface of the first beam and have a linear shape extending along the first beam, and portions that protrude from the second surface of the second beam and have a linear shape extending along the second beam, and the plurality of ribs are positioned on the first surface such that, when viewed from a viewpoint facing the first surface, they form a grid pattern surrounding at least one of the openings. A method for manufacturing a vapor deposition mask.

9. This includes forming a pattern on a deposition target using a deposition mask manufactured by the deposition mask manufacturing method described in any one of claims 6 to 8. A method for manufacturing a display device.

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