CN106350768A - Metal mask for vapor deposition and method for manufacturing metal mask for vapor deposition - Google Patents

Abstract

The invention provides a metal mask for vapor deposition and a method for manufacturing the metal mask for vapor deposition, which can improve both the structural accuracy of a pattern formed by vapor deposition and the operability of the metal mask for vapor deposition. The disclosed device is provided with: a mask section (32) which has a contact surface for contacting a deposition target and a non-contact surface on the opposite side of the contact surface, is formed in a sheet shape, and has a plurality of mask holes that penetrate from first openings located on the contact surface to second openings located on the non-contact surface, respectively, wherein the first openings are smaller in size than the second openings; and a mask frame (31) having higher rigidity than the mask portion and formed in a frame shape surrounding the plurality of mask holes. The mask portion (32) has a portion surrounding the plurality of mask holes in the non-contact surface, and is joined to the mask frame at the portion via a joint portion.

Description

Metal mask for vapor deposition and method for manufacturing metal mask for vapor deposition

technical field

The present invention relates to a metal mask for vapor deposition and a method for manufacturing the metal mask for vapor deposition.

Background technique

When vapor-depositing a vapor-deposition target such as a substrate with a vapor-deposition substance, a metal mask may be used. This vapor deposition metal mask has a contact surface and a non-contact surface. The contact surface is a surface that comes into contact with a vapor deposition target. The non-contact surface is the surface opposite to the contact surface. The mask hole penetrating from the non-contact surface to the contact surface has a non-contact side opening and a contact side opening. The opening on the non-contact side is an opening on the non-contact surface through which vapor deposition substances enter. The contact side opening is located on the contact surface and faces the vapor deposition target. The vapor deposition substance entering from the opening on the non-contact side and passing through the opening on the contact side deposits on the vapor deposition target. Thereby, a pattern depending on the position and shape of the opening on the contact side is formed (for example, refer to JP-A-2015-055007).

In order to improve the accuracy of the position on the pattern, etc., the via cross-sectional area of the mask hole of the metal mask for vapor deposition decreases monotonously from the non-contact side opening toward the contact side opening. In recent years, in order to improve the accuracy of pattern film thickness uniformity, etc., it is also desired to reduce the distance between the non-contact side opening and the contact side opening, that is, the thickness of the metal mask for vapor deposition.

On the other hand, in a thin metal mask for vapor deposition, sufficient mechanical resistance of the metal mask for vapor deposition cannot be obtained, so the handleability of the metal mask for vapor deposition is remarkably low.

Contents of the invention

An object of the present invention is to provide a metal mask for vapor deposition capable of achieving both improvement in structural accuracy such as the position and film thickness of a pattern formed by vapor deposition, and improvement in the operability of the metal mask for vapor deposition. A method of manufacturing a mold and a metal mask for vapor deposition.

A metal mask for vapor deposition for solving the above-mentioned problems includes a mask portion having a contact surface for contacting a vapor deposition object and a non-contact surface opposite to the contact surface, and is formed in a sheet shape, Moreover, the mask portion has a plurality of mask holes respectively penetrating from the first opening on the contact surface to the second opening on the non-contact surface, and the size of the first opening is smaller than that of the second opening. In addition, the metal mask for vapor deposition further includes a mask frame which has higher rigidity than the mask portion and is formed in a frame shape surrounding the plurality of mask holes. The mask portion has a portion surrounding the plurality of mask holes on the non-contact surface, and the portion is joined to the mask frame by a joint portion.

A method of manufacturing a metal mask for vapor deposition for solving the above-mentioned problems includes: a step of forming a mask portion having a contact surface for contacting a vapor deposition object and a non-contact surface opposite to the contact surface. The contact surface is formed in a sheet shape, and the mask portion has a plurality of mask holes respectively penetrating from the first opening on the contact surface to the second opening on the non-contact surface, and the size of the first opening is smaller than the size of said second opening; and

A step of joining the mask portion to a mask frame, the mask frame having a higher rigidity than the mask portion and being formed in a frame shape surrounding the plurality of mask holes, and the mask portion is placed on the The non-contact surface has a portion surrounding the plurality of mask holes, and in the step of bonding the mask portion to the mask frame, the mask portion is bonded to the mask frame through a bonding portion at this portion.

According to each of the above configurations, the vapor deposition substance entering the mask hole from the second opening is deposited on the vapor deposition target through the first opening having a smaller size than the second opening. Therefore, it is possible to improve the structural accuracy of the pattern made of the vapor-deposited substance. And, the non-contact surface where the second opening is located is joined to the mask frame having higher rigidity than the mask portion. Therefore, it is easy to bring the contact surface into contact with the vapor deposition target, and the rigidity of the metal mask for vapor deposition itself can be increased, and the handleability of the metal mask for vapor deposition can also be improved.

In the said metal mask for vapor deposition, you may provide the some said mask part joined to the common one said mask frame.

In the method of manufacturing the metal mask for vapor deposition, the step of bonding the mask frame to the non-contact surface may be bonding a plurality of the mask portions to one mask frame.

According to each of the configurations described above, the number of mask holes required for one mask frame can be divided into a plurality of mask portions. Furthermore, the metal mask for vapor deposition described above is superior in the following points, compared to a configuration in which one mask portion includes all the mask holes required for one mask frame. That is, even when a part of one mask portion is deformed, the size of a new mask portion to be replaced with the deformed mask portion can be suppressed to one of a plurality of mask portions. Furthermore, consumption of various materials required for repairing the metal mask for vapor deposition can also be suppressed.

In the metal mask for vapor deposition described above, the mask part may be a metal sheet, at least one of the contact surface and the non-contact surface may include a smooth surface, and the smooth surface may be light incident on the smooth surface. The reflectivity of specular reflection is 45.2% or more, and the thickness of the metal sheet is 50 μm or less.

In the above-mentioned method for manufacturing a metal mask for vapor deposition, the mask part may be a metal sheet, at least one of the contact surface and the non-contact surface may include a smooth surface, and the smooth surface may be provided facing toward the smooth surface. The reflectance of specular reflection of incident light is 45.2% or more, and the thickness of the metal sheet is 50 μm or less.

The thinner the thickness of the mask portion, the more pronounced the effect of being joined to the mask frame. According to each of the above configurations, the above effects can be obtained for a thin mask portion having a thickness of 50 μm or less.

In the metal mask for vapor deposition described above, the mask part may be a metal sheet, at least one of the contact surface and the non-contact surface may include a smooth surface, and the smooth surface may be light incident on the smooth surface. The reflectivity of specular reflection is 53.0% or more, and the thickness of the metal sheet is 40 μm or less.

In the above-mentioned method for manufacturing a metal mask for vapor deposition, the mask part may be a metal sheet, at least one of the contact surface and the non-contact surface may include a smooth surface, and the smooth surface may be provided facing toward the smooth surface. The reflectance of specular reflection of incident light is 53.0% or more, and the thickness of the metal sheet is 40 μm or less.

According to each of the above configurations, the above effects can be obtained for a thin mask portion having a thickness of 40 μm or less.

In the above metal mask for vapor deposition, the mask frame may include a plane on which the bonding portion is located, and the plane may have a size extending toward the outside of the mask portion.

According to the metal mask for vapor deposition described above, the plane joined to the non-contact surface extends toward the outside of the mask portion. That is, the mask frame has a surface structure in which the non-contact surface of the sheet-shaped mask portion virtually expands. Therefore, a space corresponding to the thickness of the mask portion is easily formed around the mask portion in the range in which the plane of the mask frame spreads. As a result, it is possible to suppress physical interference between the vapor deposition target in contact with the contact surface and the mask frame.

Description of drawings

FIG. 1 is a plan view showing a planar structure of a mask apparatus according to one embodiment.

FIG. 2 is a cross-sectional view partially showing an example of a cross-sectional structure of a mask portion.

3 is a cross-sectional view partially showing another example of a cross-sectional structure of a mask portion.

4 is a cross-sectional view partially showing an example of a joint structure between an edge of a mask portion and a mask frame.

5 is a cross-sectional view partially showing another example of the joint structure between the edge of the mask portion and the mask frame.

6 is a diagram showing an example of the relationship between the number of mask holes included in a metal mask for vapor deposition and the number of mask holes included in each mask portion, and (a) shows a metal mask for vapor deposition. The plan view of the planar structure of a mask, (b) is a cross-sectional view which shows the cross-sectional structure of the metal mask for vapor deposition.

7 is a diagram showing another example of the relationship between the number of mask holes included in the metal mask for vapor deposition and the number of mask holes included in the mask portion, and (a) shows the metal mask for vapor deposition. (b) is a plan view showing a planar structure of a mold, and (b) is a cross-sectional view showing a cross-sectional structure of a metal mask for vapor deposition.

8 is a cross-sectional view showing a cross-sectional structure of an example of a metal mask substrate for vapor deposition.

9 is a cross-sectional view showing a cross-sectional structure of another example of a metal mask substrate for vapor deposition.

FIG. 10 is a graph showing the relationship between the production methods, the surface roughness of the sheet-facing surface of the metal mask base for vapor deposition, and the reflectance of the sheet-facing surface of the metal mask base for vapor deposition.

FIG. 11 is a graph showing the reflectance of the sheet-facing surface of each metal mask base material for vapor deposition.

12 is a diagram illustrating an example of a method of manufacturing a metal mask for vapor deposition according to an embodiment, and (a) to (h) are process diagrams each showing a flow of steps.

13 is a diagram illustrating another example of the method of manufacturing the metal mask for vapor deposition according to one embodiment, and (a) to (e) are process diagrams showing the flow of the steps, respectively.

14 is a diagram illustrating another example of the method of manufacturing the metal mask for vapor deposition according to one embodiment, and (a) to (f) are process diagrams showing the flow of the steps, respectively.

Explanation of symbols

F…stress, S…evaporation object, V…space, EPS…electrode surface, H1…back opening, H2…surface opening, PR…resist layer, RM…resist mask, SH…step height, T1, T32…thickness, TM…intermediate transfer substrate, 10…mask unit, 20…main frame, 21…main frame hole, 30…metal mask for vapor deposition, 31…mask frame, 31E…inside edge of frame , 32, 32A, 32B, 32C... mask part, 32BN... joint part, 32E... peripheral edge part, 32H... mask hole, 32K... base material, 32LH... mask large hole, 32SH... mask small hole, 33 , 33A, 33B, 33C... mask frame hole, 311... frame back, 312... frame surface, 321... mask back, 322... mask surface, 323... mask sheet.

detailed description

One embodiment of the metal mask for vapor deposition and the manufacturing method of the metal mask for vapor deposition will be described with reference to FIGS. 1 to 14 .

[Mask device]

As shown in FIG. 1 , the mask device 10 includes a main frame 20 and a plurality of metal masks 30 for vapor deposition. The main frame 20 has a rectangular frame shape supporting a plurality of vapor deposition metal masks 30 . The main frame 20 is attached to a vapor deposition device for vapor deposition. The main frame 20 has a plurality of main frame holes 21 . Each main frame hole 21 covers almost the entire range where each vapor deposition metal mask 30 is located, and penetrates through the main frame 20 .

The metal mask 30 for vapor deposition includes a mask frame 31 and a plurality of mask portions 32 . The mask frame 31 has a short strip shape that supports the mask portion 32 . The mask frame 31 is attached to the main frame 20 . The mask frame 31 has a plurality of mask frame holes 33 . Each mask frame hole 33 covers substantially the entire range where the corresponding mask portion 32 is located, and penetrates the mask frame 31 . The mask frame 31 has higher rigidity than the mask portion 32 and has a frame shape surrounding each mask frame hole 33 . Each mask portion 32 is fixed to the frame inner edge portion of the mask frame 31 defining the corresponding mask frame hole 33 by welding or bonding.

Next, an example of the cross-sectional structure of the mask portion 32 will be described with reference to FIG. 2 , and another example of the cross-sectional structure of the mask portion 32 will be described with reference to FIG. 3 .

An example of the mask portion 32 is constituted by a mask sheet 323 as in the example shown in FIG. 2 . The mask sheet 323 is any one of a single metal sheet, a multilayer metal sheet, and a laminated body of a metal sheet and a resin sheet. The metal sheet constituting the mask sheet 323 is made of nickel or iron-nickel alloy. The material of the metal sheet constituting the mask sheet 323 is, for example, an iron-nickel alloy containing more than 30% by mass of nickel, and among them, an alloy of 36% by mass nickel and 64% by mass of iron is an invar-iron-nickel alloy. (invar). In the case of an alloy of 36% by mass nickel and 64% by mass iron as the main component, the remaining components include additives such as chromium, manganese, carbon, and cobalt. When the metal sheet constituting the mask sheet 323 is an Invar sheet, the thermal expansion coefficient of the metal sheet is, for example, about 1.2×10 ⁻⁶ /°C. With the mask sheet 323 having such a coefficient of thermal expansion, the degree of thermal expansion of the mask portion 32 matches the degree of thermal expansion of the glass substrate. Therefore, it is preferable to use a glass substrate as an example of a vapor deposition target.

The mask sheet 323 has a mask back surface 321 as an example of a contact surface. The mask sheet 323 has a mask surface 322 that is an example of a non-contact surface, and the mask surface 322 is a surface opposite to the mask back surface 321 . The mask surface 322 is a surface for facing the vapor deposition source in the vapor deposition apparatus. The mask back surface 321 is a surface to be in contact with a vapor deposition target such as a glass substrate in the vapor deposition apparatus.

The thickness of the mask sheet 323 , that is, the distance between the mask surface 322 and the mask back surface 321 is 1 μm to 100 μm, preferably 1 μm to 50 μm, more preferably 2 μm to 40 μm. If the thickness of the mask sheet 323 is 40 μm or less, the depth of the mask hole 32H formed in the mask sheet 323 is 40 μm or less. Such a thinner mask sheet 323 is superior in the following points. That is, when the vapor deposition target is observed from the particles of the vapor deposition substance flying toward the mask sheet 323 (vapor deposition particles), compared with the thicker mask sheet 323, the metal mask 30 for vapor deposition can not The part that can be attached (the part that will be blocked) is reduced. In other words, shadow effects can be suppressed.

Each mask portion 32 has a plurality of mask holes 32H penetrating the mask sheet 323 . The hole side faces that define the mask hole 32H have an inclination with respect to the thickness direction of the mask sheet 323 in a cross-sectional view. The shape of the side surface of the hole defining the mask hole 32H may be a straight line in a cross-sectional view, a semicircular arc protruding toward the outside of the mask hole 32H, or a complex curved shape with multiple bending points. .

The mask surface 322 includes a second opening of each mask hole 32H, ie, a surface opening H2. The mask back surface 321 includes a back surface opening H1 which is the first opening of each mask hole 32H. When viewed from above, the size of the surface opening H2 is larger than the size of the rear opening H1 . Each mask hole 32H is a passage through which vapor deposition particles sublimated from a vapor deposition source pass. The vapor deposition particles sublimated from the vapor deposition source enter from the front opening H2 toward the back opening H1 . As long as the surface opening H2 is larger than the mask hole 32H of the rear opening H1, the shadow effect on the vapor deposition particles entering through the surface opening H2 can be suppressed. In addition, the area of the mask hole 32H in a cross section parallel to the mask back surface 321 may increase monotonically from the back opening H1 to the front opening H2 as the cross section moves from the back opening H1 to the front opening H2. Big. In other words, the cross-sectional area of the mask hole 32H may decrease monotonously from the front opening H2 toward the rear opening H1 . Such a mask hole 32H can further suppress the shadow effect described above.

In another example shown in FIG. 3 , each mask portion 32 has a plurality of mask holes 32H penetrating through the mask sheet 323 . In the example shown in FIG. 3 , the size of the front opening H2 is larger than the size of the rear opening H1 in plan view. Each mask hole 32H is composed of a mask large hole 32LH having a front opening H2 and a mask small hole 32SH having a back opening H1. The mask large hole 32LH is a hole whose cross-sectional area decreases monotonously from the front surface opening H2 toward the mask back surface 321 . The mask small hole 32SH is a hole whose cross-sectional area decreases monotonously from the rear opening H1 toward the mask surface 322 . The hole side surface defining each mask hole 32H has a portion connecting the mask large hole 32LH and the mask small hole 32SH in a cross-sectional view. The portion where the large mask hole 32LH connects to the small mask hole 32SH is located in the middle of the mask sheet 323 in the thickness direction. The mask large hole 32LH and the portion connected to the mask small hole 32SH have a shape protruding toward the inside of the mask hole 32H. The distance between the hole side surface of the mask hole 32H protruding most inward and the mask back surface 321 is the step height SH. The cross-sectional structure described above in FIG. 2 is an example in which the step height SH is made zero. From the viewpoint of suppressing the above-mentioned shading effect, it is preferable that the step height SH is zero. In addition, in order to obtain the mask portion 32 with a step height SH of zero, for example, the thickness of the mask sheet 323 is preferably 40 μm or less so that the mask hole 32H is formed by wet etching from the mask surface 322 to the mask back surface 321, There is no need for wet etching from the mask backside 321 .

[Joining of mask part]

Next, an example of the cross-sectional structure of the joint structure between the mask portion 32 and the mask frame 31 will be described with reference to FIG. 4 . Another example of the cross-sectional structure of the joint structure between the mask portion 32 and the mask frame 31 will be described with reference to FIG. 5 .

As in the example shown in FIG. 4 , a region in which no mask hole 32H is formed continues on the outer peripheral edge portion 32E of the mask sheet 323 . On the mask surface 322 of the mask sheet 323 , a portion included in the outer peripheral edge portion 32E of the mask sheet 323 is joined to the mask frame 31 . The mask frame 31 includes a frame inner edge portion 31E that defines each mask frame hole 33 . The frame inner edge portion 31E has a frame back surface 311 facing the mask sheet 323 . The frame inner edge portion 31E has a frame surface 312 that is a surface opposite to the frame back surface 311 . The thickness T31 of the frame inner edge portion 31E, that is, the distance between the frame back surface 311 and the frame surface 312, is thicker than the thickness T32 of the mask sheet 323, whereby the mask frame 31 has higher rigidity than the mask sheet 323. . In particular, the mask frame 31 has higher rigidity than the mask sheet 323 when the frame inner edge 31E hangs down due to its own weight or when the frame inner edge 31E is displaced toward the center of the mask portion 32 . The bonding portion 32BN that is bonded to the mask surface 322 is located on the frame back surface 311 of the frame inside edge portion 31E.

The joining portion 32BN is arranged continuously or intermittently over substantially the entire circumference of the frame inner edge portion 31E. The bonding portion 32BN is a welding mark formed by welding the frame back surface 311 and the mask surface 322 . The weld line is a mixture of the material constituting the mask frame 31 and the material constituting the mask portion 32 . Alternatively, the bonding portion 32BN is a bonding layer that bonds the frame back surface 311 and the mask surface 322 . The bonding layer contains a material different from the material constituting the mask frame 31 and the material constituting the mask portion 32 . In the mask frame 31 , the frame back surface 311 of the frame inside edge portion 31E is bonded to the mask surface 322 of the mask sheet 323 . Since the mask surface 322 is bonded to the mask frame 31 , the rigidity of the metal mask for vapor deposition 30 itself can be increased compared to a metal mask for vapor deposition that does not include the mask frame 31 .

The mask frame 31 applies a stress F such that each mask sheet 323 is pulled toward the outside of the mask sheet 323 to the mask sheet 323 . In addition, a stress such that the mask frame 31 is pulled toward the outside of the mask frame 31 is also applied by the main frame 20 to the mask frame 31 . The magnitude of this stress is about the same as the stress F of the mask sheet 323 . Therefore, in the vapor deposition metal mask 30 detached from the main frame 20 , the stress due to the bonding between the main frame 20 and the mask frame 31 is released, and the stress F applied to the mask sheet 323 is also relieved. The position of the bonding portion 32BN on the frame back surface 311 is preferably a position where the stress F acts isotropically on the mask sheet 323 . The position of the bonding portion 32BN on the frame back surface 311 is appropriately selected based on the shape of the mask sheet 323 and the shape of the mask frame hole 33 .

The thickness of the mask sheet 323 constituting the mask portion 32 is, for example, 1 μm or more and 50 μm or less. At least one of the mask surface 322 and the mask back surface 321 includes a smooth surface in a region surrounding the mask hole 32H. The smooth surface is set so that, for example, the reflectance of specular reflection of light incident on the smooth surface is 45.2% or more. Alternatively, for the smooth surface, for example, the three-dimensional surface roughness Sa is 0.11 μm or less, and the three-dimensional surface roughness Sz is 3.17 μm or less.

The metal sheet constituting the mask sheet 323 is manufactured by any of the following methods: (A) deposition of a metal material based on electrolysis; (B) rolling and grinding of a metal material; (C) deposition of a metal material based on electrolysis and Grinding; (D) Rolling of metallic materials only. The thinner the thickness of the mask part 32 is, the more prominent the effect of the bonding between the mask frame 31 and the mask part 32 is. According to the mask portion 32 exemplified above, the above-described effect can be obtained for the thin mask portion 32 having a thickness of 50 μm or less.

In addition, in metal flakes, the thinner the thickness of the metal flakes, the higher the reflectance of the surface of the metal flakes tends to be. In addition, in the metal sheet, the thinner the thickness of the metal sheet, the smaller the three-dimensional surface roughness Sa and the three-dimensional surface roughness Sz of the surface of the metal sheet tend to be. In addition, when the wet etching for forming the mask hole 32H is performed from the surface of the mask sheet 323, since the surface of the mask sheet 323 includes the above-mentioned smooth surface, it is also possible to improve the resistance to the resist mask formed on the surface. of closeness.

The thickness of the mask sheet 323 constituting the mask portion 32 is, for example, 2 μm or more and 40 μm or less. Also in this configuration, at least one of the mask surface 322 and the mask back surface 321 includes a smooth surface in a region surrounding the mask hole 32H. The smooth surface is set so that, for example, the reflectance of specular reflection of light incident on the smooth surface is 53.0% or more. Alternatively, for the smooth surface, for example, the three-dimensional surface roughness Sa is 0.019 μm or less, and the three-dimensional surface roughness Sz is 0.308 μm or less. According to the mask portion 32 exemplified here, a particularly excellent effect can be obtained for an extremely thin mask portion 32 having a thickness of 40 μm or less. In addition, when performing wet etching for forming the mask hole 32H from the surface of the mask sheet 323, since the surface of the mask sheet 323 includes the above-mentioned smooth surface, the size of the resist mask formed on the surface can also be reduced. The minimum resolution size of .

In addition, the reflectance R was calculated from the following formula (1) by measuring the reflected light reflected by the specular surface when the light emitted from the halogen lamp was incident on the target surface. The light emitted from the halogen lamp is incident on the area of ^14mm2 of the target surface at an incident angle of 45°±0.2° relative to the normal direction of the target surface. The area of the element that receives the reflected light is 11.4 mm ² .

Reflectance R=[light amount of reflected light reflected by mirror surface/light amount of incident light]×100...(1)

In addition, three-dimensional surface roughness Sa and Sz are the values measured by the method based on ISO25178. The three-dimensional surface roughness Sa is the arithmetic mean height in a defined area having a prescribed area. The three-dimensional surface roughness Sz is the maximum height in a defined area with a prescribed area.

The frame back surface 311 is a plane on which the bonding portion 32BN is located. The frame back surface 311 extends from the outer peripheral edge portion 32E of the mask surface 322 toward the outside of the mask sheet 323 . In other words, the frame inside edge portion 31E has a plane configuration in which the mask surface 322 virtually expands toward the outside of the mask surface 322 . The frame inside edge portion 31E extends from the outer peripheral edge portion 32E of the mask surface 322 toward the outside of the mask sheet 323 . A space V corresponding to the thickness of the mask sheet 323 is easily formed around the mask sheet 323 in the range where the frame back surface 311 extends. As a result, physical interference between the vapor deposition target S and the mask frame 31 can be suppressed around the mask sheet 323 .

In the example shown in FIG. 5 , there is also a region in which no mask hole 32H is formed continues on the outer peripheral edge portion 32E of the mask sheet 323 . The outer peripheral edge portion 32E of the mask surface 322 is bonded to the frame back surface 311 included in the mask frame 31 by bonding by the bonding portion 32BN. The mask frame 31 applies a stress F such that each mask sheet 323 is pulled toward the outside of the mask sheet 323 to the mask sheet 323 . The mask frame 31 forms a space V corresponding to the thickness of the mask sheet 323 in the range where the frame back surface 311 extends.

[Number of Mask Sections]

Next, an example of the relationship between the number of mask holes 32H included in the vapor deposition metal mask 30 and the number of mask holes 32H included in each mask portion 32 will be described with reference to FIG. 6 . In addition, another example of the relationship between the number of mask holes 32H included in the vapor deposition metal mask 30 and the number of mask holes 32H included in the mask portion 32 will be described with reference to FIG. 7 .

As shown in the example of FIG. 6( a ), the mask frame 31 has, for example, three mask frame holes 33 as a plurality of mask frame holes 33 . As shown in the example of FIG. 6( b ), the metal mask 30 for vapor deposition includes one mask portion 32 in each mask frame hole 33 . That is, the frame inside edge portion 31E defining the mask frame hole 33A is joined to one mask portion 32A. The other frame inside edge portion 31E defining the mask frame hole 33B is joined to the other mask portion 32B. The remaining one frame inside edge portion 31E defining the mask frame hole 33C is joined to the remaining one mask portion 32C.

Metal mask 30 for vapor deposition can be used repeatedly for a plurality of vapor deposition objects. Therefore, the plurality of mask holes 32H included in the vapor deposition metal mask 30 are required to have high precision in the position of the mask hole 32H, the structure of the mask hole 32H, and the like. As in the configuration shown in FIG. 6 , compared with the configuration in which the number of mask holes 32H required for one mask frame 31 is borne by one mask portion 32 , the number of mask holes 32H required for one mask frame 31 The configuration in which the number of 32H is covered by three mask portions 32 is more excellent in the following points. For example, when a part of one mask portion 32 is deformed, the size of a new mask portion 32 to be replaced with the deformed mask portion 32 can be reduced. In addition, it is also possible to suppress consumption of various materials required for manufacturing and repairing the metal mask 30 for vapor deposition. In addition, the inspection related to the structure of the mask hole 32H is preferably performed in a state where the mask frame 31 and the mask portion 32 are bonded. From this viewpoint, it is preferable that the above-mentioned joint portion 32BN has a configuration in which the deformed mask portion 32 can be replaced with a new mask portion 32 . In addition, the thinner the thickness of the mask sheet 323 constituting the mask portion 32 and the smaller the size of the mask hole 32H, the easier it is for the yield of the mask portion 32 to decrease. Therefore, the configuration in which each mask frame hole 33 has one mask portion 32 is suitable also for the metal mask 30 for vapor deposition requiring high definition.

As shown in the example of FIG. 7( a ), the mask frame 31 has, for example, three mask frame holes 33 as a plurality of mask frame holes 33 . As shown in the example of FIG.7(b), the metal mask 30 for vapor deposition is equipped with the one mask part 32 shared by the some mask frame hole 33. As shown in FIG. That is, the frame inner edge portion 31E defining the mask frame hole 33A, the frame inner edge portion 31E defining the mask frame hole 33B, and the frame inner edge portion 31E defining the mask frame hole 33C are shared with them. One mask portion 32 is bonded.

In addition, if the number of mask holes 32H required for one mask frame 31 is covered by one mask portion 32 , the number of mask portions 32 joined to the mask frame 31 can be reduced to one. Therefore, the load required for bonding the mask frame 31 and the mask portion 32 can be reduced. In addition, the thicker the mask sheet 323 constituting the mask portion 32 and the larger the size of the mask hole 32H, the easier it is to improve the yield of the mask portion 32 . Therefore, the configuration including the mask portion 32 shared by the respective mask frame holes 33 is suitable for the metal mask 30 for vapor deposition requiring low resolution.

[Manufacturing method of metal mask for vapor deposition]

Next, each example of the manufacturing method of the metal mask for vapor deposition is demonstrated. In addition, FIG. 8 and FIG. 9 each show an example of the metal mask base material for vapor deposition used in the manufacturing method using wet etching. FIG. 10 shows the characteristics of the sheet-object surface of the metal sheet 32S included in the metal mask base material for vapor deposition. FIG. 11 shows the reflectance of the sheet object surface included in the metal sheet 32S. A part of the sheet object surface includes a smooth surface of the mask sheet 323 . The sheet object surface has the same surface properties as the smooth surface throughout the entirety of the sheet object surface.

In addition, an example of a method of forming a mask hole by wet etching will be described with reference to FIG. 12 . In addition, an example of a method of forming a mask hole by electrolysis will be described with reference to FIG. 13 . Another example of a method of forming a mask hole by electrolysis will be described with reference to FIG. 14 .

In addition, compared with the method of manufacturing the metal mask 30 for vapor deposition described in FIG. 2 and the method of manufacturing the metal mask 30 for vapor deposition described in FIG. The method of etching the mold base material 32K is different, but the other steps are almost the same. Hereinafter, the method of manufacturing the metal mask 30 for vapor deposition described in FIG. 2 will be mainly described, and the redundant description of the method of manufacturing the metal mask 30 for vapor deposition described in FIG. 3 will be omitted.

The metal sheet 32S has a mask surface 322 and a mask back surface 321 .

In the method of forming a resist mask on the mask surface 322 and forming the mask piece 323 by etching from the mask surface 322 , the mask surface 322 is a piece object surface. In the method of forming respective resist masks on the mask surface 322 and the mask back surface 321, and forming the mask piece 323 by etching from the mask surface 322 and etching from the mask back surface 321, the mask The mold surface 322 and the mask backside 321 are sheet object surfaces. The sheet object surface is a surface on which a resist mask is formed in the process of forming a metal mask for vapor deposition.

The material constituting the metal sheet 32S is nickel or an iron-nickel alloy, for example, an iron-nickel alloy containing more than 30% by mass of nickel, and this is because an alloy of 36% by mass of nickel and 64% by mass of iron is the main component. Iron-nickel alloy. When the metal piece 32S is an Invar piece, the thermal expansion coefficient of the metal piece 32S is, for example, about 1.2×10 ⁻⁶ /°C. If the metal sheet 32S having such a thermal expansion coefficient is used, the degree of thermal expansion of the mask portion 32 manufactured using the metal sheet 32S matches the degree of thermal expansion of the glass substrate, so glass is suitably used as an example of the vapor deposition target. substrate.

The thickness T1 of the metal sheet 32S is, for example, 1 μm to 100 μm, preferably 1 μm to 50 μm, more preferably 2 μm to 40 μm. If the thickness T1 which the metal piece 32S has is 40 micrometers or less, the depth of the hole formed in the metal piece 32S can be made into 40 micrometers or less. The metal sheet 32S having such a thickness T1 is excellent in the following points in the metal mask for vapor deposition manufactured using the metal sheet 32S. That is, when the film formation target is observed from the vapor deposition particles flying toward the vapor deposition metal mask, it is possible to reduce the portion that is undesirably blocked by the vapor deposition metal mask. In other words, shadow effects can be suppressed.

It is preferable that the surface properties of the sheet object surface of the metal sheet 32S satisfy at least one of the following [Condition 1] and [Condition 2].

[Condition 1] Three-dimensional surface roughness Sa≦0.019 μm or less and three-dimensional surface roughness Sz≦0.308 μm or less.

[Condition 2] 53.0%≦reflectance R≦97.0% of the target surface.

The three-dimensional surface roughness Sa and Sz are values measured by a method based on ISO 25178. The reflectance R was calculated from the following formula (2) by measuring the reflected light of the specular reflection when the light emitted from the halogen lamp was incident on the target surface. The light emitted from the halogen lamp is incident on the area of ^14mm2 of the target surface at an incident angle of 45°±0.2° relative to the normal direction of the target surface. The area of the element that receives the reflected light is 11.4 mm ² .

Reflectance R=[light amount of reflected light reflected by mirror surface/light amount of incident light]×100...(2)

If the surface properties satisfy at least one of [Condition 1] and [Condition 2], it is possible to suppress scattering of light irradiated on the target surface by the target surface. In addition, when light is irradiated to the resist layer on the resist target surface, it is possible to suppress a part of the light from being scattered by the target surface, and the scattered light can irradiate regions other than the exposure target region in the resist layer. As a result, the difference between the structure of the resist mask formed by exposure and development and the designed resist mask can be suppressed, and the structure of the mask hole 32H formed by wet etching can be suppressed from being different from the designed one. A difference occurs between the configurations of the designed mask holes 32H.

In addition, as shown in FIG. 9 , the metal mask base material for vapor deposition can further include a resin body PB on at least one of the mask back surface 321 and the mask surface 322 in addition to the metal sheet 32S. That is, the metal mask base material for vapor deposition can be embodied as a laminated body of the metal sheet 32S and the resin body PB. The material constituting the resin body PB on the mask surface 322 is a resist. The material constituting the resin body PB located on the mask back surface 321 is, for example, resist or polyimide.

When the material constituting the resin body PB is a resist, the resin body PB is a resist layer. The resist layer as the resin body PB is pasted to the mask surface 322 after being formed into a sheet shape. Alternatively, the resist layer as the resin body PB is formed by applying a coating liquid for forming a resist layer to the mask surface 322 .

When the material constituting the resin body PB is polyimide, the resin body PB is in close contact with the mask back surface 321 . The thermal expansion coefficient of polyimide and its temperature dependence are about the same as those of Invar and its temperature dependence. Therefore, the temperature of the resin body PB produced by the temperature change of the resin body PB Expansion and contraction prevent warping of the metal sheet 32S.

The thickness T2 of the resin body PB is, for example, not less than 5 μm and not more than 50 μm. From the viewpoint of improving the mechanical strength of the laminated body of the resin body PB and the metal sheet 32S, the thickness T2 of the resin body PB is preferably 5 μm or more. In addition, in the process of forming the mask part 32, the resin body PB may be removed from the metal piece 32S by immersing in alkaline solution etc. in some cases. From the viewpoint of suppressing the time required for such removal from becoming too long, the thickness of the resin body PB is preferably 50 μm or less.

The manufacturing method of the metal sheet used any of the following methods: (A) electrolysis; (B) rolling and grinding; (C) electrolysis and grinding; (D) rolling only.

In addition, when forming the base material for rolling for manufacturing the metal sheet 32S, oxygen mixed in the material for forming the base material for rolling is generally removed. When removing oxygen mixed in the material, for example, a deoxidizer such as granular aluminum or magnesium is mixed with the material for forming the base material. As a result, aluminum and magnesium are contained in the base material as metal oxides such as alumina and magnesia. Before the base metal is rolled, most of the metal oxides are removed from the base metal. On the other hand, a part of the metal oxide remains in the base material to be rolled. In this regard, according to the manufacturing method using electrolysis, it is possible to suppress the mixing of metal oxides into the metal piece 32S.

(A) electrolysis

When electrolysis is used as a method of manufacturing the metal piece 32S, the metal piece 32S is formed on the surface of an electrode used for electrolysis. Then, the metal piece 32S is separated from the surface of the electrode. In this way, the metal sheet 32S having the mask surface 322 serving as the sheet object surface and the mask back surface 321 which is the surface previously in contact with the electrode surface is manufactured. When the surface of the electrode has the same level of surface properties as the sheet target surface, both the mask surface 322 and the mask back surface 321 of the metal sheet 32S have surface properties equivalent to the sheet target surface. When the surface of the electrode has larger surface roughness and lower reflectance than the sheet target surface, the mask surface 322 of the metal sheet 32S has surface characteristics equivalent to the sheet target surface. In addition, in the configuration in which both the mask surface 322 and the mask back surface 321 have surface properties equivalent to those of the sheet object surface, when a resist layer is formed on the sheet object surface, the mask surface 322 and the mask back surface 321 can be relieved. difference in the required load. In addition, the separated metal piece 32S may be annealed after being separated.

The electrolytic bath used for electrolysis contains, for example, an iron ion supplier, a nickel ion supplier, and a pH buffer. In addition, the electrolytic bath used for electrolysis may contain a stress relieving agent, a Fe ³⁺ ion masking agent, a complexing agent such as malic acid, citric acid, etc., and may be a weakly acidic solution adjusted to a pH suitable for electrolysis. The iron ion supplier is, for example, ferrous sulfate heptahydrate, ferrous chloride, iron sulfamate, or the like. The nickel ion supplier is, for example, nickel(II) sulfate, nickel(II) chloride, nickel sulfamate, or nickel bromide. pH buffering agents are, for example, boric acid, malonic acid. Malonic acid also functions as a masking agent for Fe ³⁺ ions. A stress relieving agent is, for example, sodium saccharin. The electrolytic bath used for electrolysis is, for example, an aqueous solution containing the above-mentioned additives, and the pH is adjusted to, for example, 2 or more and 3 or less with a pH regulator such as 5% sulfuric acid or nickel carbonate.

The electrolysis conditions used for the electrolysis are conditions in which the surface properties of the sheet object surface, the composition ratio of nickel in the metal sheet 32S, and the like are adjusted according to the temperature of the electrolytic bath, current density, and electrolysis time. The anode under the electrolytic conditions using the electrolytic bath is, for example, pure iron and nickel. The cathode under electrolysis conditions is, for example, a stainless steel plate such as SUS304. The temperature of the electrolytic bath is, for example, not less than 40°C and not more than 60°C. The current density is, for example, not less than 1 A/dm ² and not more than 4 A/dm ² .

(B) grinding

The metal piece 32S before grinding may be manufactured by electrolysis, or may be manufactured by rolling. In the method of manufacturing the unpolished metal sheet 32S by rolling, first, a metallic base material is rolled, and then the rolled base material is annealed. At this time, the level difference on the surface of the metal piece 32S before grinding is smaller than the level difference on the surface of the base material. In addition, the level difference of the back surface of the metal piece 32S before grinding|polishing is smaller than the level difference of the back surface of a base material. Then, chemical or electrical polishing is performed on the surface of the metal piece 32S before polishing. Thus, the metal sheet 32S having a polished surface, that is, a sheet target surface, is produced.

The polishing liquid used in the chemical polishing is, for example, a chemical polishing liquid for an iron-based alloy mainly composed of hydrogen peroxide. Electrolytic solutions used in electropolishing are perchloric acid-based electrolytic polishing solutions and sulfuric acid-based electrolytic polishing solutions. In addition, the metal sheet 32S before grinding can be embodied, for example, as a sheet in which a rolled metal sheet is processed thinner by wet etching with an acidic etchant.

An example of the three-dimensional surface roughness Sa, the three-dimensional surface roughness Sz, the reflectance R, and the processing accuracy of the resist mask of the metal sheet 32S will be described with reference to FIGS. 10 and 11 . FIG. 10 shows the three-dimensional surface roughness Sa, the three-dimensional surface roughness Sz, and the reflectance R of each level from Test Example 1 to Test Example 9. FIG. FIG. 11 shows the respective reflectances of Test Example 1, Test Example 2, Test Example 3, and Test Example 9, which are representative examples in each level from Test Example 1 to Test Example 9. FIG.

As shown in FIG. 10 , each of Test Example 1, Test Example 2, Test Example 3, Test Example 6, and Test Example 7 is a metal sheet 32S having a thickness of 20 μm produced by electrolysis (A) above. Test Example 4 and Test Example 5 are metal pieces 32S each having a thickness of 20 μm produced by grinding the metal piece 32S produced by (B) rolling. Moreover, the metal piece 32S manufactured by (A) electrolysis has the surface which contacts an electrode. At this time, the three-dimensional surface roughness Sa of the electrode made of SUS was 0.018 μm, and the three-dimensional surface roughness Sz was 0.170 μm. Test Example 8 and Test Example 9 are the metal pieces 32S manufactured by rolling, respectively, and are the metal pieces 32S not subjected to grinding. The respective thicknesses of Test Example 8 and Test Example 9 are 10 μm thicker than the respective thicknesses of Test Example 4 and Test Example 5, which is the polishing amount of Test Example 4 and Test Example 5.

Test example 1, test example 2, test example 3, test example 6, test example 7 are respectively by using the aqueous solution that has added following additive, and be adjusted to the electrolytic bath of pH2.3, and current density is at 1 (A /dm ² ) to 4 (A/dm ² ) or less. In Test Example 1, Test Example 2, Test Example 3, Test Example 6, and Test Example 7, the composition ratios of iron and nickel are different from each other.

(Electrolyte for test example)

· Ferrous sulfate hydrate: 83.4g

・Nickel(II) sulfate hexahydrate: 250.0g

・Nickel(II) chloride hexahydrate: 40.0g

· Boric acid: 30.0g

·Saccharin sodium water mixture: 2.0g

Malonic acid: 5.2g

·Temperature: 50℃

Experiment 4 and Experiment 5 were obtained by performing chemical polishing using a hydrogen peroxide-based chemical polishing liquid on the unpolished metal sheet 32S obtained by rolling, respectively.

Test Example 8 and Test Example 9 are metal pieces 32S obtained by rolling in Test Examples 4 and 5, respectively, and are at a level where chemical polishing is not performed.

In each level from Test Example 1 to Test Example 7, it was confirmed that the three-dimensional surface roughness Sa of the sheet target surface was 0.019 μm or less, and the three-dimensional surface roughness Sz of the sheet target surface was 0.308 μm or less. On the other hand, in each level of Test Example 8 and Test Example 9, the three-dimensional surface roughness Sa of the sheet object surface was approximately 0.04 μm. From this, it can be confirmed that in the metal sheet 32S produced by the above (A) electrolysis, (B) rolling, and grinding, the three-dimensional surface roughness Sa is greatly reduced as the thinner metal sheet 32S is obtained. . In addition, in each level of Test Example 8 and Test Example 9, the three-dimensional surface roughness Sz of the sheet facing surface was 0.35 μm or more. From this, it was confirmed that the three-dimensional surface roughness Sz was reduced as the thinner metal sheet 32S was obtained in the metal sheet 32S produced by the above-mentioned (A) electrolysis, (B) rolling, and grinding.

As shown in FIGS. 10 and 11 , in each level from Test Example 1 to Test Example 3, it was confirmed that the above-mentioned reflectance R was 53.0% or more and 97.0% or less. On the other hand, in each level of Test Example 8 and Test Example 9, it was confirmed that the reflectance R was smaller than 53.0% and had a larger half width than the other Test Examples. From this, it was confirmed that a large reflectance R of 53.0% or more can be obtained in the metal sheet 32S produced by the above-mentioned (A) electrolysis, (B) rolling, and grinding.

It can be confirmed that the size of the minimum resolution of the resist mask formed on each of the sheet object surfaces of Test Example 1 to Test Example 7 is, when a circular hole is formed in the resist layer by exposure to ultraviolet light, Dispersion is within the range of 4 μm to 5 μm. On the other hand, the minimum resolution size of the resist mask formed by the same manufacturing method on the respective sheet surfaces of Test Example 8 and Test Example 9 is that when a circle is formed on the resist layer by exposure to ultraviolet light, When forming a hole, it is 7 μm or more.

As in the examples shown in FIGS. 12( a ) to ( h ), in one example of the method of manufacturing a metal mask for vapor deposition, first, a metal mask base material for vapor deposition that is a base material of the mask sheet 323 is prepared. 32K (see Fig. 12(a)). In addition, it is preferable that the metal mask base material 32K for vapor deposition is equipped with the support body SP for supporting the metal sheet 32S other than the metal sheet 32S processed into the mask sheet 323. Next, a resist layer PR is formed on the mask surface 322 of the vapor deposition metal mask base material 32K (see FIG. 12( b )), and exposure and development of the resist layer PR are performed. Thus, a resist mask RM is formed on the mask surface 322 (see FIG. 12( c )). Next, by wet etching from the mask surface 322 using the resist mask RM, the mask hole 32H is formed in the vapor deposition metal mask base material 32K (see FIG. 12( d )). At this time, a surface opening H2 is formed on the mask surface 322 where wet etching from the mask surface 322 toward the mask back surface 321 has started, and a surface opening H2 smaller than the surface opening H2 is formed on the mask back surface 321 that is etched later than that. The back opening H1. Next, the resist mask RM is removed from the mask surface 322 to manufacture the above-mentioned mask portion 32 (see FIG. 12( e )). Finally, the outer peripheral edge portion 32E of the mask surface 322 is joined to the frame inner edge portion 31E of the mask frame 31, and the support body SP is released from the mask portion 32, thereby manufacturing the metal mask 30 for vapor deposition ( Referring to Figure 12 (f) to (h)).

In addition, in the manufacturing method of the vapor deposition metal mask 30 demonstrated in FIG. The surface of the mold base material 32K is subjected to the above steps. Thus, the mask hole 32SH is formed. Next, a resist or the like for protecting the mask hole 32SH is filled in the mask hole 32SH. Next, the above-described steps are performed on the surface of the vapor deposition metal mask base material 32K corresponding to the mask surface 322 , thereby manufacturing the mask portion 32 .

For example, when the mask sheet 323 is formed of a metal sheet made of an iron-nickel alloy, electrolysis and rolling are used in the process of preparing the metal mask base material 32K for vapor deposition. As the post-processing of the vapor deposition metal mask base material 32K, polishing, annealing, and the like are appropriately used.

In the case of using the support body SP, for example, the support body SP is bonded to the metal piece 32S formed on the surface of the electrode. Next, as a laminated body of the metal sheet 32S and the support body SP, the metal mask base material 32K for vapor deposition is separated from the electrode surface.

When rolling is used, the base material for manufacturing the metal sheet 32S is rolled, and then the metal sheet 32S manufactured by rolling is annealed to obtain the vapor deposition metal mask base material 32K. At this time, in the case of using the support body SP, the support body SP is joined to the metal piece 32S produced by rolling.

In addition, the metal sheet 32S obtained by electrolysis and the metal sheet 32S obtained by rolling may be processed thinner by wet etching with an acidic etchant, or may be processed thinner by chemical mechanical polishing.

In the example shown in FIG. 12( f ), resistance welding is used as a method of joining the outer peripheral edge portion 32E of the mask surface 322 and the frame inner edge portion 31E of the mask frame 31 . At this time, a plurality of through-holes SPH are formed in the insulating support body SP. Each of the through-holes SPH is formed in a portion of the support body SP that faces a portion serving as the bonding portion 32BN. Then, intermittent bonding portions 32BN are formed by energization through the through-holes SPH in a state where a stress toward the outside of the mask portion 32 is applied to the mask portion 32 . Thus, the outer peripheral edge portion 32E and the frame inner edge portion 31E are welded.

In the example shown in FIG. 12( g ), laser welding is used as a method of joining the outer peripheral edge portion 32E of the mask surface 322 and the frame inner edge portion 31E of the mask frame 31 . At this time, using the support body SP which has translucency, the laser beam L is irradiated to the site|part which becomes the junction part 32BN via the support body SP. Then, the intermittent bonding portion 32BN is formed by intermittently irradiating the laser light L, or the continuous bonding portion 32BN is formed by continuously irradiating the laser L. Thus, the outer peripheral edge portion 32E and the frame inner edge portion 31E are welded. In addition, when the support body SP supports the mask part 32 in the state where the stress toward the outside of the mask part 32 is applied to the mask part 32, the stress to the mask part 32 can also be omitted in this welding. apply.

In the example shown in FIG. 12( h ), ultrasonic welding is used as a method of joining the outer peripheral edge portion 32E of the mask surface 322 and the frame inner edge portion 31E of the mask frame 31 . At this time, the outer peripheral edge portion 32E and the frame inner edge portion 31E are clamped by the clamp CP or the like, and ultrasonic waves are applied to the portion to be the joining portion 32BN. The member to which ultrasonic waves are directly applied may be the mask frame 31 or the mask portion 32 . Moreover, when ultrasonic welding is used, the pressing mark by the clip CP is formed in the mask frame 31 and the support body SP.

As in the example shown in Fig. 13 (a) to (e), in another example of the manufacturing method of the metal mask for vapor deposition, first, a resist is formed on the surface of the electrode EP used for electrolysis, that is, the electrode surface EPS. Agent layer PR (refer to FIG. 13( a )). Next, by exposing and developing the resist layer PR, a resist mask RM which is an example of a pattern is formed on the electrode surface EPS (see FIG. 13( b )). The resist mask RM has, in a cross section perpendicular to the electrode surface EPS, an inverted truncated cone shape whose top is located on the electrode surface EPS, and has an area of a cross section parallel to the electrode surface EPS as the distance from the electrode surface EPS increases. The larger the shape. Next, electrolysis using the electrode surface EPS with the resist mask RM is performed. Thereby, the metal piece 32S is formed as the mask part 32 so that it may spread to the area|region other than the resist mask RM in electrode surface EPS (refer FIG.12(c)).

At this time, since the metal piece 32S is accumulated outside the space occupied by the resist mask RM, a hole having a shape following the shape of the resist mask RM is formed in the metal piece 32S. Then, the mask hole 32H of the mask portion 32 is formed in a self-aligning manner. That is, the surface in contact with the electrode surface EPS functions as the mask back surface 321 having the back opening H1. In addition, the outermost surface of the surface opening H2 , which is an opening larger than the back surface opening H1 , functions as a mask surface 322 .

Next, only the resist mask RM is removed from the electrode surface EPS to form a hollow mask hole 32H from the rear opening H1 to the front opening H2 (see FIG. 13( d )). Finally, the frame back surface 311 of the frame inner edge portion 31E is joined to the outer peripheral edge portion 32E of the mask surface 322 having the surface opening H2, and then stress for peeling the mask portion 32 from the electrode surface EPS is applied to the mask frame 31. . Alternatively, the mask portion 32 bonded to the support or the like is peeled off from the electrode surface EPS, and the outer peripheral edge portion 32E of the mask surface 322 is bonded to the frame back surface 311 of the frame inner edge portion 31E. Thereby, the metal mask 30 for vapor deposition in the state which joined the mask part 32 to the mask frame 31 is manufactured (refer FIG.12(e)).

14 (a) ~ (f) as shown in the example, in another example of the method of manufacturing the metal mask for vapor deposition, first, on the electrode surface EPS used in electrolysis to form a resist layer PR (refer to FIG. 14(a)). Next, by exposing and developing the resist layer PR, a resist mask RM which is an example of a pattern is formed on the electrode surface EPS (see FIG. 14( b )). The resist mask RM has a frustum shape having a bottom located on the electrode surface EPS in a cross section perpendicular to the electrode surface EPS, and has a cross-sectional area parallel to the electrode surface EPS that becomes larger as the distance from the electrode surface EPS increases. small shape. Next, electrolysis using the electrode surface EPS having the resist mask RM is performed, and the metal piece 32S is formed as the mask portion 32 (see FIG. 14(c)).

Here also, since the metal piece 32S is deposited outside the space occupied by the resist mask RM, a hole having a shape following the shape of the resist mask RM is formed in the metal piece 32S. Then, the mask hole 32H of the mask portion 32 is formed in a self-aligning manner. That is, the surface in contact with the electrode surface EPS functions as the mask surface 322 having the surface opening H2, and the outermost surface having the back opening H1, which is an opening smaller than the surface opening H2, functions as the mask back surface 321.

Next, only the resist mask RM is removed from the electrode surface EPS to form a hollow mask hole 32H from the rear opening H1 to the front opening H2 (see FIG. 14( d )). Then, the intermediate transfer base material TM is bonded to the mask back surface 321 having the back surface opening H1, and then stress for peeling the mask portion 32 from the electrode surface EPS is applied to the intermediate transfer base material TM. Thereby, the mask surface 322 peels from the electrode surface EPS in the state which bonded the mask part 32 to the intermediate transfer base material TM (refer FIG.14(e)). Finally, the frame back surface 311 of the frame inner edge portion 31E is joined to the outer peripheral edge portion 32E of the mask surface 322 having the surface opening H2 , and then the intermediate transfer substrate TM is peeled off from the mask portion 32 . Thereby, metal mask 30 for vapor deposition in the state which joined the mask part 32 to the mask frame 31 is manufactured (refer FIG.14(f)).

According to the above-described embodiment, the effects listed below can be obtained.

(1) The vapor deposition substance entering the mask hole 32H from the front opening H2 is deposited on the vapor deposition target through the rear opening H1 having a smaller size than the front opening H2 . Therefore, it is possible to improve the structural accuracy of the pattern made of the vapor-deposited substance.

(2) Since the mask surface 322 is bonded to the mask frame 31 , the mask back surface 321 can be easily brought into contact with the vapor deposition target, and the rigidity of the vapor deposition metal mask 30 itself can be increased.

(3) The number of mask holes 32H required for one mask frame 31 is divided into three mask sections 32 , for example. Therefore, even when a part of one mask portion 32 is deformed, the size of a new mask portion 32 to be replaced with the deformed mask portion 32 can be reduced.

(4) In an example in which the cross-sectional area of the mask hole 32H decreases monotonously from the front opening H2 to the rear opening H1 , the shadow effect can be more favorably suppressed for the vapor deposition particles entering from the front opening H2 .

(5) Since the mask hole 32H having a shape following the shape of the resist mask RM is formed by electrolysis, the burden of etching the metal sheet separately for forming the mask hole 32H is reduced.

Claims (9)

1. A metal mask for vapor deposition, wherein: The mask portion is provided with a contact surface for contacting with the vapor deposition object and a non-contact surface on the opposite side to the above-mentioned contact surface, and is formed in a sheet shape, and the mask portion has first openings that pass through the contact surface respectively. a plurality of mask holes to a second opening located on the non-contact surface, the size of the first opening being smaller than the size of the second opening; and The mask frame has a higher rigidity than the mask portion and is formed in a frame shape surrounding the plurality of mask holes, The mask portion has a portion surrounding the plurality of mask holes on the non-contact surface, and the portion is joined to the mask frame by a joint portion. 2. The metal mask for vapor deposition according to claim 1, wherein: A plurality of the above-mentioned mask portions joined to the common one of the above-mentioned mask frames are provided. 3. The metal mask for vapor deposition according to claim 1 or 2, wherein: The mask portion is a metal sheet, At least one of the contact surface and the non-contact surface includes a smooth surface, and the smooth surface has a reflectance of specular reflection of light incident on the smooth surface of 45.2% or more, The metal sheet has a thickness of 50 μm or less. 4. The metal mask for vapor deposition according to claim 1 or 2, wherein: The mask portion is a metal sheet, At least one of the contact surface and the non-contact surface includes a smooth surface, and the smooth surface has a reflectance of specular reflection of light incident on the smooth surface of 53.0% or more, The metal sheet has a thickness of 40 μm or less. 5. The metal mask for vapor deposition according to claim 3, wherein: The mask frame has a plane on which the bonding portion is located, The flat surface has a size extending toward the outside of the mask portion. 6. A method of manufacturing a metal mask for vapor deposition, comprising: A process of forming a mask portion having a contact surface for contacting with an evaporation target and a non-contact surface opposite to the contact surface, formed in a sheet shape, and having The first opening of the contact surface penetrates to a plurality of mask holes located at the second opening of the non-contact surface, and the size of the first opening is smaller than the size of the second opening; and A step of joining the mask portion to a mask frame, the mask frame having a higher rigidity than the mask portion and being formed in a frame shape surrounding the plurality of mask holes, and the mask portion is placed on the The non-contact surface has a portion surrounding the plurality of mask holes, and in the step of bonding the mask portion to the mask frame, the mask portion is bonded to the mask frame through a bonding portion at this portion. 7. The method of manufacturing a metal mask for vapor deposition according to claim 6, wherein: The step of bonding the mask frame to the non-contact surface is to bond the plurality of mask portions to one mask frame. 8. The method of manufacturing a metal mask for vapor deposition according to claim 6 or 7, wherein: The mask portion is a metal sheet, At least one of the contact surface and the non-contact surface includes a smooth surface, and the smooth surface has a reflectance of specular reflection of light incident on the smooth surface of 45.2% or more, In the step of forming the mask portion, the thickness of the metal sheet is set to be 50 μm or less. 9. The method of manufacturing a metal mask for vapor deposition according to claim 6 or 7, wherein: The mask portion is a metal sheet, At least one of the contact surface and the non-contact surface includes a smooth surface, and the smooth surface has a reflectance of specular reflection of light incident on the smooth surface of 53.0% or more, In the step of forming the mask portion, the thickness of the metal sheet is set to be 40 μm or less.