JP5382257B1 - Metal plate, method for producing metal plate, and method for producing vapor deposition mask using metal plate - Google Patents

Abstract

A metal plate capable of producing a vapor deposition mask with small warpage is provided.
When a sample taken out from a metal plate after an annealing process is etched, a curvature k of the warp of the sample after etching is 0.008 mm ⁻¹ or less.
[Selection] Figure 9

Description

  The present invention relates to a metal plate used for manufacturing a vapor deposition mask by forming a plurality of through holes. The present invention also relates to a method for manufacturing a metal plate. Moreover, this invention relates to the method of manufacturing the vapor deposition mask used in order to vapor-deposit with a desired pattern using a metal plate.

  In recent years, a display device used in a portable device such as a smartphone or a tablet PC is required to have high definition, for example, a pixel density of 300 ppi or more. In portable devices, there is an increasing demand for supporting full high vision, and in this case, the pixel density of the display device is required to be, for example, 450 ppi or more.

  Organic EL display devices are attracting attention because of their good responsiveness and low power consumption. As a method of forming pixels of an organic EL display device, a method of forming pixels with a desired pattern using a vapor deposition mask including through holes arranged in a desired pattern is known. Specifically, first, a vapor deposition mask is brought into close contact with the substrate for the organic EL display device, and then, the vapor deposition mask and the substrate that are brought into close contact with each other are put into the vapor deposition device to perform vapor deposition of an organic material or the like. Generally, a vapor deposition mask can be manufactured by forming a through-hole in a metal plate by etching using a photolithography technique (for example, Patent Document 1).

JP 2004-39319 A

  When a vapor deposition material is formed on a substrate using a vapor deposition mask, the vapor deposition material adheres not only to the substrate but also to the vapor deposition mask. For example, some vapor deposition materials are directed to the substrate along a direction that is largely inclined with respect to the normal direction of the vapor deposition mask, but such vapor deposition material is vapor deposited before reaching the substrate. It reaches the wall surface of the through hole of the mask and adheres. In this case, the vapor deposition material is less likely to adhere to the region of the substrate located near the wall surface of the through hole of the vapor deposition mask. As a result, the thickness of the deposited vapor deposition material may be smaller than other portions. It is conceivable that a portion where the vapor deposition material is not attached may be generated. That is, it is considered that the vapor deposition in the vicinity of the wall surface of the through hole of the vapor deposition mask becomes unstable. Therefore, when a vapor deposition mask is used to form a pixel of the organic EL display device, the dimensional accuracy and position accuracy of the pixel are lowered, and as a result, the light emission efficiency of the organic EL display device is lowered. Become.

  In order to solve such a problem, it is conceivable to reduce the thickness of the metal plate used for manufacturing the vapor deposition mask. Because, by reducing the thickness of the metal plate, the height of the wall surface of the through hole of the vapor deposition mask can be reduced, thereby reducing the proportion of the vapor deposition material that adheres to the wall surface of the through hole. Because you can. However, in order to obtain a metal plate having a small thickness, it is necessary to increase the rolling rate when the metal plate is manufactured by rolling the base material. Here, the rolling rate is a value calculated by (base material thickness−metal plate) / (base material thickness). Even when heat treatment such as annealing is performed after rolling, the higher the rolling rate, the greater the residual stress on the metal plate, that is, the residual stress. When the residual stress is large, when the through hole is formed in the metal plate by etching, the residual stress is released on the side of the metal plate to be etched, and as a result, the obtained deposition mask is warped. When the warp is large, the vapor deposition mask cannot be sufficiently adhered to the substrate for the organic EL display device, and as a result, the dimensional accuracy and position accuracy of the pixel of the obtained organic EL display device are lowered.

  An object of this invention is to provide the manufacturing method of the metal plate which can solve such a subject effectively, the manufacturing method of a metal plate, and a vapor deposition mask.

1st this invention is a manufacturing method of the metal plate used in order to form a some through-hole, and to manufacture a vapor deposition mask, Comprising: The said through-hole of the said vapor deposition mask etches the said metal plate. The method of manufacturing the metal plate includes: a rolling step of rolling a base material to obtain the metal plate having a thickness t ₀ ; and annealing the metal plate to generate an internal stress of the metal plate. An annealing step for removing the sample, and the metal plate has a first surface and a second surface that are orthogonal to the thickness direction and opposed to each other, and is taken out of the metal plate after the annealing step when etching the curvature k of the warp of the samples after etching is at 0.008 mm ^-1 or less, the curvature k, first, before the length 170 mm, the sample width 30mm after the annealing step Removed from the metal plate, then across the length 150mm excluding the region is within 10 mm, thickness _{1/3 × t 0 ~2 /} 3 × the etched region of the width of 30mm in the length direction of the sample The sample is etched over the entire area to be etched from the side of the first surface until it falls within the range of t ₀ , and then the etched sample is mounted in a predetermined manner so that the side surface is horizontal. Place on the mounting table, and then measure the distance x (mm) between the ends of the sample in the length direction of the etched region and the warp depth y (mm) of the etched region of the sample, Thereafter, the distance between the end portions x and the depth y are expressed by the following equations k = 1 / ρ, ρ = (y / 2) + (x ² / 8y)
This is a method for manufacturing a metal plate, which is a value obtained by substituting for.

  In the method for manufacturing a metal plate according to the present invention, the annealing step may be performed while pulling the metal plate in the length direction.

  In the method of manufacturing a metal plate according to the present invention, the annealing step may be performed in a state where the metal plate is wound around a core.

  In the method for producing a metal plate according to the present invention, preferably, the coefficient of thermal expansion of the metal plate is equal to the coefficient of thermal expansion of a substrate on which a deposition material is formed through a deposition mask manufactured from the metal plate. It has become.

  In the manufacturing method of the metal plate by this invention, the said metal plate may be comprised from the invar material.

The second present invention is a metal plate used for manufacturing an evaporation mask to form a plurality of through-holes, said metal plate has a thickness t _0, and the metal plate has a thickness When the sample taken from the metal plate has a first surface and a second surface that are orthogonal to the direction and face each other, the curvature k of the warped sample after etching is 0.008 mm ⁻¹ or less. Yes, the curvature k is first 150 mm long and 30 mm wide sample taken out from the metal plate, and then the length of 150 mm excluding the region within 10 mm from both ends in the length direction of the sample, to a thickness of the etched region of width 30mm is within the range of _{1/3 × t 0 ~2 /} 3 × t 0, from the side of the first surface, the sample over the entire of the etched region The sample that has been etched and then etched is placed on a predetermined mounting table so that the side surface thereof is horizontal, and then the distance between end portions x ( mm) and the depth y (mm) of warpage of the etched region of the sample, and then the end-to-end distance x and the depth y are expressed by the following equations k = 1 / ρ, ρ = ( y / 2) + (x ² / 8y)
It is a metal plate which is a value calculated | required by substituting for.

  The thermal expansion coefficient of the metal plate according to the present invention is preferably a value equivalent to the thermal expansion coefficient of the substrate on which the vapor deposition material is formed through the vapor deposition mask manufactured from the metal plate.

  The metal plate by this invention may be comprised from the invar material.

A third invention is a method of producing an effective region in which a plurality of through holes are formed, and the surrounding region located around the effective area, an evaporation mask having a metal plate having a thickness t ₀ A step of preparing a metal plate having a first surface and a second surface that are orthogonal to the thickness direction and opposed to each other, and etching the metal plate from the side of the first surface; Forming a recess from the first surface side in the region of the metal plate that forms the through hole, and etching the sample taken out from the metal plate If you are a curvature k of the warp of the samples after etching 0.008 mm ^-1 or less, the curvature k is initially taken out length 170 mm, the sample width 30mm from the metal plate, then the sample Of length excluding the region is within 10mm from both ends in the length direction 150 mm, until the thickness of the etched region of width 30mm falls within a range of _{1/3 × t 0 ~2 /} 3 × t 0, the first The sample is etched from the side of one surface over the entire region to be etched, and then the etched sample is placed on a predetermined mounting table so that the side surface is horizontal, and then the sample And measuring the distance x (mm) between the end portions in the length direction of the etched region and the depth y (mm) of the warp of the etched region of the sample, and then measuring the distance x between the end portions and the depth. Y is expressed by the following equation: k = 1 / ρ, ρ = (y / 2) + (x ² / 8y)
It is the manufacturing method of a vapor deposition mask which is the value calculated | required by substituting for.

  In the recess forming step of the vapor deposition mask manufacturing method according to the present invention, the metal plate may be etched from the first surface side to the entire first surface.

In the recess forming step of the method for manufacturing a vapor deposition mask according to the present invention, the metal plate has the thickness from the side of the first surface until the thickness is within a range of 1/3 × t ₀ to 2/3 × t _0. Etching may be performed over the entire first surface.

  In the method for manufacturing a vapor deposition mask according to the present invention, preferably, the coefficient of thermal expansion of the metal plate is equal to the coefficient of thermal expansion of the substrate on which the vapor deposition material is formed through the vapor deposition mask manufactured from the metal plate. It has become.

  In the vapor deposition mask manufacturing method according to the present invention, the metal plate may be made of an invar material.

  According to the present invention, it is possible to obtain a vapor deposition mask with small warpage. For this reason, a vapor deposition mask can fully contact | adhere with respect to a board | substrate, As a result, the dimensional accuracy and position accuracy of vapor deposition material adhering on a board | substrate can be improved.

FIG. 1 is a schematic perspective view showing an embodiment of the present invention and showing an example of a vapor deposition mask device including a vapor deposition mask. FIG. 2 is a view for explaining a method of vapor deposition using the vapor deposition mask apparatus shown in FIG. FIG. 3 is a partial plan view showing the vapor deposition mask shown in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view taken along line VV in FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. Fig.7 (a) is a figure which shows the process of rolling a base material and obtaining the metal plate which has desired thickness, FIG.7 (b) is the process of annealing the metal plate obtained by rolling. FIG. FIG. 8A is a diagram showing a sample cut out from the metal plate obtained by the steps shown in FIGS. 7A and 7B, and FIG. 8B is a diagram of the sample shown in FIG. 8A. The figure which shows the etched sample obtained by etching 1 surface. FIGS. 9A and 9B are a perspective view and a plan view showing a state in which the etched sample shown in FIG. 8B is placed on the placing table. FIG. 10 is a schematic diagram for entirely explaining an example of the manufacturing method of the vapor deposition mask shown in FIG. FIG. 11 is a diagram for explaining an example of a method for manufacturing a vapor deposition mask, and is a diagram showing a long metal plate in a cross section along the normal direction. FIG. 12 is a view for explaining an example of a method of manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along the normal direction. FIG. 13 is a view for explaining an example of a method of manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along a normal direction. FIG. 14 is a view for explaining an example of a method of manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along the normal direction. FIG. 15 is a view for explaining an example of a method for manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along a normal direction. FIG. 16 is a view for explaining an example of a method for manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along the normal direction. FIG. 17 is a view for explaining an example of a method for manufacturing a vapor deposition mask, and is a view showing a long metal plate in a cross section along a normal direction. FIG. 18 is a diagram for explaining a modification of the vapor deposition mask and the vapor deposition mask device. FIGS. 19A to 19C are diagrams for explaining a method of taking a sample from a metal plate in the examples.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  1-17 is a figure for demonstrating one Embodiment by this invention. In the following embodiments and modifications thereof, a method for manufacturing a vapor deposition mask used for patterning an organic material on a substrate in a desired pattern when manufacturing an organic EL display device will be described as an example. However, the present invention can be applied to a method of manufacturing a vapor deposition mask used for various purposes without being limited to such application.

  In the present specification, the terms “plate”, “sheet”, and “film” are not distinguished from each other only based on the difference in names. For example, “a plate” is a concept that includes a member that can be called a sheet or a film. Therefore, for example, a “metal plate” is distinguished from a member called “a metal sheet” or “a metal film” only by a difference in the name. Cannot be done.

  In addition, “plate surface (sheet surface, film surface)” means a target plate-like member (sheet-like) when the target plate-like (sheet-like, film-like) member is viewed as a whole and globally. It refers to the surface that coincides with the plane direction of the member or film-like member. Moreover, the normal direction used with respect to a plate-like (sheet-like, film-like) member refers to the normal direction with respect to the plate | board surface (sheet surface, film surface) of the said member.

  Further, as used herein, the shape, geometric conditions and physical characteristics and their degree are specified, for example, terms such as “parallel”, “orthogonal”, “identical”, “equivalent”, lengths and angles In addition, values of physical characteristics and the like are not limited to a strict meaning and are interpreted to include a range where a similar function can be expected.

(Deposition mask device)
First, an example of a vapor deposition mask apparatus including a vapor deposition mask to be a manufacturing method will be described mainly with reference to FIGS. Here, FIG. 1 is a perspective view showing an example of a vapor deposition mask apparatus including a vapor deposition mask, and FIG. 2 is a view for explaining a method of using the vapor deposition mask apparatus shown in FIG. FIG. 3 is a plan view showing the vapor deposition mask from the first surface side, and FIGS. 4 to 6 are cross-sectional views at respective positions in FIG.

  The vapor deposition mask device 10 shown in FIGS. 1 and 2 includes a vapor deposition mask 20 made of a rectangular metal plate 21 and a frame 15 attached to the peripheral edge of the vapor deposition mask 20. The vapor deposition mask 20 is provided with a large number of through holes 25 formed by etching the metal plate 21 having the first surface 21a and the second surface 21b facing each other from at least the first surface 21a. As shown in FIG. 2, the vapor deposition mask device 10 is supported in the vapor deposition device 90 so that the vapor deposition mask 20 faces the lower surface of a substrate, for example, a glass substrate 92, as a vapor deposition target, and vapor deposition material for the substrate. Used for vapor deposition.

  In the vapor deposition apparatus 90, the vapor deposition mask 20 and the glass substrate 92 come into close contact by a magnetic force from a magnet (not shown). In the vapor deposition apparatus 90, a crucible 94 for accommodating a vapor deposition material (for example, an organic light emitting material) 98 and a heater 96 for heating the crucible 94 are disposed below the vapor deposition mask apparatus 10. The vapor deposition material 98 in the crucible 94 is vaporized or sublimated by heating from the heater 96 and adheres to the surface of the glass substrate 92. As described above, a large number of through holes 25 are formed in the vapor deposition mask 20, and the vapor deposition material 98 adheres to the glass substrate 92 through the through holes 25. As a result, the vapor deposition material 98 is formed on the surface of the glass substrate 92 in a desired pattern corresponding to the position of the through hole 25 of the vapor deposition mask 20.

(Deposition mask)
Next, the vapor deposition mask 20 will be described in detail. As shown in FIG. 1, in the present embodiment, the vapor deposition mask 20 is made of a metal plate 21 and has a substantially rectangular shape in a plan view, more precisely a substantially rectangular shape in a plan view. The metal plate 21 of the vapor deposition mask 20 includes an effective area 22 in which the through holes 25 are formed in a regular arrangement, and a surrounding area 23 surrounding the effective area 22. The surrounding area 23 is an area for supporting the effective area 22 and is not an area through which a deposition material intended to be deposited on the substrate passes. For example, in the vapor deposition mask 20 used for vapor deposition of an organic light emitting material for an organic EL display device, the effective region 22 is a region on the substrate (glass substrate 92) where the organic light emitting material is deposited to form a pixel. That is, it is a region in the vapor deposition mask 20 that faces an area on the substrate that forms the display surface of the produced substrate for an organic EL display device. However, through holes and recesses may be formed in the peripheral region 23 for various purposes. In the example shown in FIG. 1, each effective region 22 has a substantially rectangular shape in plan view, more precisely, a substantially rectangular shape in plan view.

  In the illustrated example, the plurality of effective regions 22 are arranged at a predetermined interval along one direction parallel to one side of the vapor deposition mask 20 and have a predetermined value along another direction orthogonal to the one direction. They are spaced apart. In the illustrated example, one effective area 22 corresponds to one organic EL display device. That is, according to the vapor deposition mask apparatus 10 (deposition mask 20) shown in FIG. 1, vapor deposition with multiple surfaces is possible.

  As shown in FIG. 3, in the illustrated example, the plurality of through holes 25 formed in each effective region 22 are arranged at a predetermined pitch along two directions orthogonal to each other in the effective region 22. Yes. An example of the through hole 25 formed in the metal plate 21 will be described in more detail with reference mainly to FIGS.

  As shown in FIGS. 4 to 6, the plurality of through-holes 25 are formed on the first surface 20 a on one side along the normal direction of the vapor deposition mask 20 and on the other side along the normal direction of the vapor deposition mask 20. The vapor deposition mask 20 is penetrated by extending between the second surface 20b as a side. In the illustrated example, as will be described in detail later, a first recess 30 is formed in the metal plate 21 by etching from the first surface 21a side of the metal plate 21 which is one side in the normal direction of the vapor deposition mask. The second concave portion 35 is formed in the metal plate 21 from the second surface 21b side which is the other side in the normal direction of the metal plate 21, and the through hole 25 is formed by the first concave portion 30 and the second concave portion 35. ing.

  As shown in FIGS. 3 to 6, the plate surface of the vapor deposition mask 20 at each position along the normal direction of the vapor deposition mask 20 from the first surface 20 a side to the second surface 20 b side of the vapor deposition mask 20. The cross-sectional area of each first recess 30 in the cross section along the line gradually decreases. As shown in FIG. 3, the wall surface 31 of the first recess 30 extends in a direction intersecting with the normal direction of the vapor deposition mask 20 in the entire region, and one wall surface along the normal direction of the vapor deposition mask 20. It is exposed to the side. Similarly, the cross-sectional area of each second recess 35 in the cross section along the plate surface of the vapor deposition mask 20 at each position along the normal direction of the vapor deposition mask 20 is the second cross-sectional area from the second surface 20b side of the vapor deposition mask 20. It may be gradually reduced toward the first surface 20a. The wall surface 36 of the second recess 35 extends in a direction intersecting the normal direction of the vapor deposition mask 20 in the entire region, and is exposed toward the other side along the normal direction of the vapor deposition mask 20. Yes.

  As shown in FIGS. 4 to 6, the wall surface 31 of the first recess 30 and the wall surface 36 of the second recess 35 are connected via a circumferential connection portion 41. The connecting portion 41 is an overhanging portion where the wall surface 31 of the first recess 30 inclined with respect to the normal direction of the vapor deposition mask and the wall surface 36 of the second recess 35 inclined with respect to the normal direction of the vapor deposition mask merge. It is defined by the ridgeline. And the connection part 41 defines the penetration part 42 in which the area of the through-hole 25 becomes the smallest in the planar view of the vapor deposition mask 20.

  As shown in FIGS. 4 to 6, two adjacent through holes 25 on the other surface along the normal direction of the vapor deposition mask, that is, the second surface 20 b of the vapor deposition mask 20, are formed on the vapor deposition mask. They are separated from each other along the plate surface. That is, when the metal plate 21 is etched from the side of the second surface 21b of the metal plate 21 that corresponds to the second surface 20b of the vapor deposition mask 20, as in the manufacturing method described later, the second recess 35 is produced. The second surface 21b of the metal plate 21 remains between two adjacent second recesses 35.

  On the other hand, as shown in FIGS. 4 to 6, two adjacent first recesses 30 are connected on the other side along the normal direction of the vapor deposition mask, that is, on the first surface 20 a side of the vapor deposition mask 20. ing. That is, when the metal plate 21 is etched from the side of the first surface 21a of the metal plate 21 corresponding to the first surface 20a of the vapor deposition mask 20 to form the first recess 30 as in the manufacturing method described later. The first surface 21 a of the metal plate 21 does not remain between the two adjacent first recesses 30. That is, the first surface 21 a of the metal plate 21 is etched over the entire effective area 22. According to the first surface 20a of the vapor deposition mask 20 formed by such a first recess 30, the vapor deposition mask 20 is formed so that the first surface 20a of the vapor deposition mask 20 faces the vapor deposition material 98 as shown in FIG. When 20 is used, the utilization efficiency of the vapor deposition material 98 can be improved effectively.

  When the vapor deposition mask device 10 is accommodated in the vapor deposition device 90 as shown in FIG. 2, the first surface 20a of the vapor deposition mask 20 holds the vapor deposition material 98 as shown by the two-dot chain line in FIG. The second surface 20 b of the vapor deposition mask 20 faces the glass substrate 92. Therefore, the vapor deposition material 98 adheres to the glass substrate 92 through the first recess 30 whose cross-sectional area is gradually reduced. As indicated by arrows in FIG. 4, the vapor deposition material 98 not only moves from the crucible 94 toward the glass substrate 92 along the normal direction of the glass substrate 92, but also greatly increases with respect to the normal direction of the glass substrate 92. It may move in an inclined direction. At this time, when the thickness of the vapor deposition mask 20 is large, most of the vapor deposition material 98 moving obliquely reaches the wall surface 31 of the first recess 30 before reaching the glass substrate 92 through the through hole 25. Adhere. Moreover, in the area | region which faces the through-hole 25 on the glass substrate 92, the area | region where the vapor deposition material 98 reaches | attains easily and the part which cannot reach easily will arise. Therefore, the use efficiency of the vapor deposition material (deposition efficiency: ratio of adhering to the glass substrate 92) is increased to save the expensive vapor deposition material, and the film formation using the expensive vapor deposition material is stabilized in a desired region. In order to implement it uniformly, it is important to configure the vapor deposition mask 20 so that the vapor deposition material 98 moving obliquely reaches the glass substrate 92 as much as possible. That is, in the cross section of FIG. 4 to FIG. 6 orthogonal to the sheet surface of the vapor deposition mask 20, the connection portion 41 that is a portion having the minimum cross-sectional area of the through hole 25 and other arbitrary positions of the wall surface 31 of the first recess 30. It is advantageous to sufficiently increase the minimum angle θ1 (see FIG. 4) formed by the straight line L1 passing through the normal direction of the vapor deposition mask 20.

  As one method for increasing the angle θ1, it is conceivable to reduce the thickness of the vapor deposition mask 20 and thereby reduce the height of the wall surface 31 of the first recess 30 and the wall surface 36 of the second recess 35. . That is, it can be said that it is preferable to use the metal plate 21 with the smallest possible thickness within the range in which the strength of the vapor deposition mask 20 can be secured as the metal plate 21 for constituting the vapor deposition mask 20.

  As another method for increasing the angle θ1, it is conceivable to optimize the contour of the first recess 30. For example, according to the present embodiment, the wall surfaces 31 of the two adjacent first recesses 30 are merged to compare with a recess having a wall surface (contour) indicated by a dotted line that does not merge with other recesses. The angle θ1 can be greatly increased. The reason will be described below.

  The first recess 30 is formed by etching the first surface 21a of the metal plate 21, as will be described in detail later. The wall surface of the recess formed by etching is generally a curved surface that is convex toward the erosion direction. Therefore, the wall surface 31 of the recess formed by the etching is cut off in the region which is the etching start side, and in the region opposite to the etching start side, that is, in the deepest side of the recess, the method of the metal plate 21 is performed. The inclination is relatively large with respect to the line direction. On the other hand, in the illustrated deposition mask 20, the wall surfaces 31 of the two adjacent first recesses 30 merge on the etching start side, so that the leading edges 32 of the wall surfaces 31 of the two first recesses 30 merge. The outer contour of the portion 43 is not a sharp shape but a chamfered shape. For this reason, the wall surface 31 of the 1st recessed part 30 which makes most through-holes 25 can be effectively inclined with respect to the normal line direction of a vapor deposition mask. That is, the angle θ1 can be increased.

  According to the vapor deposition mask 20 according to the present embodiment, the inclination angle θ1 formed by the wall surface 31 of the first recess 30 with respect to the normal direction of the vapor deposition mask can be effectively increased in the entire effective region 22. Thereby, vapor deposition with a desired pattern can be stably performed with high accuracy while effectively improving the utilization efficiency of the vapor deposition material 98.

  Further, when the first concave portion 30 is formed by etching the metal plate 21 from the first surface 21a side of the metal plate 21 that comes to correspond to the first surface 20a of the vapor deposition mask 20 as in the manufacturing method described later, In the entire region of the metal plate 21 that forms the effective region 22 of the vapor deposition mask 20, the first surface 21a of the metal plate 21 is eroded by etching. That is, the maximum thickness Ta in the effective region 22 along the normal direction of the vapor deposition mask is less than 100% of the maximum thickness Tb in the surrounding region 23 along the normal direction of the vapor deposition mask. Thus, it is preferable from the viewpoint of improving the utilization efficiency of the vapor deposition material that the thickness in the effective region 22 is generally reduced. On the other hand, from the viewpoint of the strength of the vapor deposition mask, the maximum thickness Ta in the effective region 22 along the normal direction of the vapor deposition mask is 50 of the maximum thickness Tb in the surrounding region 23 along the normal direction of the vapor deposition mask. % Or more is preferable. When the maximum thickness Ta in the effective area 22 is 50% or more of the maximum thickness Tb in the surrounding area 23, the effective area 22 of the evaporation mask 20 when the evaporation mask 20 is stretched on the frame 15 is used. Therefore, it is possible to effectively suppress vapor deposition in a desired pattern.

  By the way, in order to obtain the metal plate 21 having a small thickness, it is necessary to increase the rolling rate when the metal plate 21 is manufactured by rolling the base material. However, the higher the rolling rate, the greater the stress remaining on the metal plate, that is, the residual stress. When the residual stress is large, when the metal plate 21 is etched to produce the vapor deposition mask 20, the residual stress is released on the side of the metal plate 21 to be etched, and as a result, the obtained vapor deposition mask 20 is warped. Will occur. If the warpage is large, the vapor deposition mask 20 cannot be sufficiently adhered to the substrate 92, and as a result, the position accuracy of vapor deposition may be reduced. Furthermore, in the present embodiment, as described above, the vapor deposition mask 20 is manufactured by etching the first surface 21a of the metal plate 21 over a wide area of the effective area 22, for example, over the entire area. Therefore, compared to the case where the first surface 21a is etched only locally, the degree of residual stress released on the first surface 21a side of the metal plate 21 is increased, and as a result, warpage may occur. The nature is also increasing. Therefore, as will be described later, it is important to select and use the metal plate 21 that does not easily warp when it becomes the vapor deposition mask 20.

  As described above, in the present embodiment, the through holes 25 are arranged in a predetermined pattern in each effective region 22. When color display is to be performed, the vapor deposition mask 20 (vapor deposition mask device 10) and the glass substrate 92 are moved relative to each other along the arrangement direction of the through holes 25 (one direction described above), and the red color is displayed. An organic light emitting material, a green organic light emitting material, and a blue organic light emitting material may be deposited in this order.

  The frame 15 of the vapor deposition mask device 10 is attached to the peripheral edge of the rectangular vapor deposition mask 20. The frame 15 holds the deposition mask in a stretched state so that the deposition mask 20 is not bent. The vapor deposition mask 20 and the frame 15 are fixed to each other, for example, by spot welding.

  The vapor deposition process is performed inside the vapor deposition apparatus 90 that is in a high temperature atmosphere. Therefore, during the vapor deposition process, the vapor deposition mask 20, the frame 15 and the substrate 92 held inside the vapor deposition apparatus 90 are also heated. At this time, the vapor deposition mask, the frame 15 and the substrate 92 exhibit dimensional change behavior based on their respective thermal expansion coefficients. In this case, if the thermal expansion coefficients of the vapor deposition mask 20 and the frame 15 and the substrate 92 are greatly different, a positional shift caused by a difference in their dimensional change occurs. As a result, the dimension of the vapor deposition material adhering to the substrate 92 is generated. Accuracy and position accuracy will be reduced. In order to solve such a problem, it is preferable that the thermal expansion coefficients of the vapor deposition mask 20 and the frame 15 are equal to the thermal expansion coefficient of the substrate 92. For example, when the glass substrate 92 is used as the substrate 92, an invar material that is an alloy obtained by adding 36% nickel to iron can be used as the material of the vapor deposition mask 20 and the frame 15.

  Next, the operation and effect of the present embodiment having such a configuration will be described. Here, the manufacturing method of the metal plate used in order to manufacture a vapor deposition mask is demonstrated first. Next, a method for manufacturing a vapor deposition mask using the obtained metal plate will be described. Then, the method to vapor-deposit vapor deposition material on a board | substrate using the obtained vapor deposition mask is demonstrated.

(Metal plate manufacturing method)
First, a method for manufacturing a metal plate will be described with reference to FIGS. 7 (a) and 7 (b), FIGS. 8 (a) and 8 (b), and FIGS. 9 (a) and 9 (b). Fig.7 (a) is a figure which shows the process of rolling a base material and obtaining the metal plate which has desired thickness, FIG.7 (b) is the process of annealing the metal plate obtained by rolling. FIG. Fig.8 (a) is a figure which shows the sample cut out from the metal plate obtained by the process shown to Fig.7 (a) (b), FIG.8 (b) is a sample shown to Fig.8 (a). It is a figure which shows the etched sample obtained by etching the 1st surface. FIGS. 9A and 9B are a perspective view and a plan view showing a state in which a sample cut out from a metal plate is placed on a placing table, respectively.

[Rolling process]
First, as shown in FIG. 7A, a base material 55 made of an invar material is prepared, and the base material 55 is conveyed toward a rolling device 56 including a pair of rolling rolls 56a and 56b. The base material 55 that has reached between the pair of rolling rolls 56a and 56b is rolled by the pair of rolling rolls 56a and 56b. As a result, the base material 55 is reduced in thickness and stretched along the conveying direction. It is. Thereby, a long metal plate 64 having a thickness t ₀ can be obtained. As shown in FIG. 7A, the wound body 62 may be formed by winding a long metal plate 64 around a core 61.

[Annealing process]
Thereafter, in order to remove the residual stress accumulated in the long metal plate 64 by rolling, the long metal plate 64 is annealed using an annealing device 57 as shown in FIG. As shown in FIG. 7B, the annealing step may be performed while pulling the long metal plate 64 in the transport direction (length direction). As a result, it is possible to obtain a long metal plate 64 having a thickness t ₀ that has been removed to the extent that there is residual stress. As shown in FIG. 7B, the wound body 62 may be formed by winding a long metal plate 64 around a core 61. The thickness t ₀ is usually equal to the maximum thickness Tb in the peripheral region 23 of the vapor deposition mask 20.

In addition, the form of a rolling process and an annealing process is not specifically limited to the form shown to Fig.7 (a) (b). For example, the rolling process may be performed using a plurality of pairs of rolling rolls 56a and 56b. Further, by repeating several times the rolling process and annealing process, may be prepared a metal plate 64 elongated in the thickness t _0. FIG. 7B shows an example in which the annealing step is performed while pulling the long metal plate 64 in the length direction. However, the annealing step is not limited to this, and the annealing step is performed on the long metal plate. You may implement in the state by which 64 was wound up by the core 61. FIG. When the annealing process is performed in a state where the long metal plate 64 is wound around the core 61, the long metal plate 64 may be warped with warping according to the winding diameter of the wound body 62. . Therefore, depending on the winding diameter of the wound body 62 and the material constituting the base material 55, it is advantageous to perform the annealing step while pulling the long metal plate 64 in the length direction.

[Inspection process]
Thereafter, an inspection process for inspecting the degree of warpage of the obtained long metal plate 64 is performed. First, as shown in FIG. 8A, a sample 75 having a length l, a width w, and a thickness t ₀ is cut out from the long metal plate 64. In FIG. 8A, the first surface and the second surface of the sample 75 are denoted by reference numerals 75a and 75b, respectively. The first surface 75 a and the second surface 75 b are surfaces that are orthogonal to the thickness direction of the sample 75 and that are opposed to each other. In FIG. 8, a pair of side surfaces located between the first surface 75a and the second surface 75b and extending in the length direction of the sample 75 are denoted by reference numerals 75c and 75d, respectively. The length l, the width w, and the thickness t ₀ are appropriately determined according to the dimensions of the vapor deposition mask 20 obtained from the long metal plate 64 as will be described later. For example, the length l is 170 mm and the width w is 30 mm, and thickness t ₀ is in the range of 0.020 to 0.100 mm.

Next, as shown in FIG. 8 (b), the thickness of the etched region 75f of the sample 75 until _{t 1,} the sample over the entire etched region 75f of the first surface 75a from the side of the first face 75a 75 Etch. The etched region 75f is a region to be etched in the sample 75. For example, the to-be-etched region 75f is a region excluding regions at distances within l ₁ and l ₂ from both ends 75g1 and 75g2 in the longitudinal direction of the sample 75, respectively. The regions of the lengths l ₁ and l ₂ near both ends 75g1 and 75g2 are regions that are not etched. Such an unetched region is useful for ensuring the stability of the sample 75 when the sample 75 is placed on the placement table, as will be described later.

As apparent from FIG. 8B, the length l ₃ of the etched region 75f in the length direction of the sample 75 is obtained by subtracting the length l ₁ and the length l ₂ from the length l of the sample 75. Become. The length l ₁ and the length l ₂ are appropriately determined so as to ensure the stability of the sample 75 when the sample 75 is placed on the placing table, and for example, both are 10 mm. In this case, the length _{l 3} of the etched region 75f in the longitudinal direction will 150 mm.

The thickness t ₁ of the sample 75 after the etching is appropriately determined according to the degree of etching performed to produce the vapor deposition mask 20. For example, the thickness t ₁ is 1/3 × t ₀ to 2/3 × t. It is within the range of ₀ . Here, since residual stress is accumulated in the sample 75 to some extent, the sample 75 is warped by etching the sample 75 from the first surface 75a side. Hereinafter, the process of measuring the curvature of warpage will be described.

As a method for evaluating the curvature of a sample, a method of calculating the curvature of the curvature of the sample while supporting one end of the sample and suspending the sample in the air is known. However, in this case, the measurement result of the curvature of curvature reflects not only the element caused by the release of the residual stress but also the element caused by the weight of the sample. Therefore, it is considered that the curvature of the sample due to the residual stress cannot be accurately evaluated. Here, according to the present embodiment, as shown in FIG. 9A, the sample 75 is placed on the predetermined placing table 76 so that the side surface 75c of the sample 75 is horizontal. Calculate the curvature of warpage. For this reason, according to this Embodiment, the curvature of the sample 75 resulting from a residual stress can be evaluated more correctly. In the vicinity of both ends 75g1 and 75g2 of the sample 75, the region having the original thickness t ₀ remains over the lengths l ₁ and l ₂ , so that the sample 75 can stably stand on the mounting table 76. it can. Moreover, it becomes easy to hold both ends 75g1 and 75g2 of the sample 75 by hand. Furthermore, when the operation of taking out the sample 75 includes a step of cutting a part of the metal plate as will be described later, since the influence of the distortion caused by the cutting is absorbed by the region having the original thickness t ₀ , It is possible to prevent or suppress the influence of the resulting distortion from reaching the etched region 75f.

Hereinafter, a specific method for calculating the curvature k of the curvature of the sample 75 will be described. FIG. 9B is a plan view showing a case where the sample 75 in a warped state along the length direction is viewed from above. In FIG. 9B, a pair of end portions in the length direction of the etched region 75f of the sample 75 is indicated by reference numeral 75e. First, the distance x (mm) between the end portions in the length direction of the etched region 75f of the sample 75 and the warp depth y (mm) of the etched region 75f of the sample 75 are measured. The warp depth y is the maximum value of the distance between the straight line connecting the pair of end portions 75e of the etched region 75f of the sample 75 and the etched region 75f of the sample 75. Next, a curvature radius ρ corresponding to the warp of the etched region 75f of the sample 75 is calculated based on the following equation.
ρ = (y / 2) + (x ² / 8y)
Next, the curvature k of the curvature of the sample 75 is calculated based on the following formula.
k = 1 / ρ
In this way, the curvature k (mm ⁻¹ ) of the curvature of the sample 75 can be obtained.

Thereafter, the long metal plate 64 is selected based on the value of the obtained curvature k. Here, the selection of the long metal plate 64 is performed in which only the long metal plate 64 from which the sample 75 whose curvature k is equal to or less than the reference value is extracted is used in the manufacturing process of the vapor deposition mask 20 described later. To do. The reference value is appropriately determined according to the positional accuracy required for vapor deposition using the vapor deposition mask 20, but for example, the long sample 75 in which the value of the curvature k is 0.008 mm ⁻¹ or less is extracted. The metal plate 64 is certified as a good product. By performing such screening, even when the vapor deposition mask 20 is warped due to etching in the manufacturing process of the vapor deposition mask 20, the degree of the warpage can be within an allowable range. . Thereby, the characteristic of the vapor deposition mask 20 manufactured can be improved. Moreover, the yield in the manufacturing process of the vapor deposition mask 20 can be improved.

  As shown in FIG. 9A, means for facilitating distance measurement, such as graph paper 77, may be provided between the mounting table and the sample 75. This facilitates the measurement of the end-to-end distance x (mm) and the warp depth y (mm), which makes it possible to quickly calculate the curvature k.

  Further, as shown in FIG. 9A, a hollow portion 76b may be formed in the mounting table 76 so that the mounting surface 76a on which the sample 75 is mounted can vibrate in the vertical direction. In this case, first, the sample 75 is placed on the placing table 76 or the graph paper 77 arranged on the placing table 76, and then the placing surface 76a is moved vertically by hitting the placing surface 76a. By vibrating, the frictional force that can be generated between the sample 75 and the mounting table 76 or the graph paper 77 can be released or reduced. Thereby, it can suppress that the influence of a frictional force appears in the measurement result of a curvature. Although the dimensions of the mounting table 76 and the hollow portion 76b are not particularly limited, for example, the width and length of the mounting table 76 are both 300 mm, and the thickness of the mounting table 76 is 50 mm. Further, the hollow portion 76b of the mounting table 76 is configured such that the thickness of the mounting surface 76a and the bottom surface of the mounting table 76 is 5 mm, respectively. Although the material which comprises the mounting base 76 is not specifically limited, For example, the mounting base 76 is comprised from the acrylic resin.

(Method for manufacturing vapor deposition mask)
Next, a method for manufacturing the vapor deposition mask 20 using the long metal plate 64 selected as described above will be described mainly with reference to FIGS. In the manufacturing method of the vapor deposition mask 20 described below, as shown in FIG. 10, a long metal plate 64 is supplied, a through hole 25 is formed in the long metal plate 64, and the long metal plate 64 is further cut. By doing so, the vapor deposition mask 20 which consists of the sheet-like metal plate 21 is obtained.

  More specifically, the manufacturing method of the vapor deposition mask 20, the step of supplying a long metal plate 64 extending in a strip shape, and etching using a photolithography technique are performed on the long metal plate 64, and the long metal plate A step of forming the first recess 30 in the first surface 64a from the side of the first surface 64a and etching using a photolithography technique are performed on the long metal plate 64, and the long metal plate 64 is subjected to the second step from the second surface 64b side. Forming the two recesses 35. And the 1st recessed part 30 and the 2nd recessed part 35 which were formed in the elongate metal plate 64 mutually communicate, and the through-hole 25 is produced in the elongate metal plate 64. FIG. In the example shown in FIG. 10, the formation process of the second recess 35 is performed before the formation process of the first recess 30, and between the formation process of the second recess 35 and the formation process of the first recess 30. In addition, a step of sealing the produced second recess 35 is further provided. Details of each step will be described below.

  FIG. 10 shows a manufacturing apparatus 60 for manufacturing the vapor deposition mask 20. As shown in FIG. 10, first, a wound body 62 in which a long metal plate 64 is wound around a core 61 is prepared. When the core 61 rotates and the wound body 62 is rewound, a long metal plate 64 extending in a strip shape is supplied as shown in FIG. The long metal plate 64 is formed with the through-hole 25 to form the sheet metal plate 21 and the vapor deposition mask 20.

The supplied long metal plate 64 is transported to an etching apparatus (etching means) 70 by a transport roller 72. Each process shown in FIGS. 11 to 17 is performed by the etching means 70. First, as shown in FIG. 11, a resist pattern (also simply referred to as a resist) 65 a is formed on the first surface 64 a of the long metal plate 64, and the resist is formed on the second surface 64 b of the long metal plate 64. A pattern (simply referred to as a resist) 65b is formed. Specifically, the following is performed. First, a negative photosensitive resist material is applied on the first surface 64 a of the long metal plate 64 (on the lower surface of the paper in FIG. 11) and on the second surface 64 b, and then on the long metal plate 64. A resist film is formed. Next, a glass dry plate is prepared in which light is not transmitted to a region to be removed of the resist film, and the glass dry plate is disposed on the resist film. Thereafter, the resist film is exposed through a glass dry plate, and the resist film is further developed. As described above, a resist pattern (simply referred to as resist) 65a is formed on the first surface 64a of the long metal plate 64, and a resist pattern (simply simply resist is formed on the second surface 64b of the long metal plate 64). 65b) can also be formed.
As the photosensitive resist material, a positive type may be used. In this case, an exposure mask in which light is transmitted through a region to be removed of the resist film is used as the exposure mask.

  Next, as shown in FIG. 12, using the resist pattern 65b formed on the long metal plate 64 as a mask, the second surface of the long metal plate 64 using an etching solution (for example, ferric chloride solution). Etching is performed from the 64b side. For example, the etching solution is sprayed toward the second surface 64b of the long metal plate 64 from the nozzle disposed on the side facing the second surface 64b of the long metal plate 64 to be conveyed through the resist pattern 65b. The As a result, as shown in FIG. 12, erosion by the etching solution proceeds in a region of the long metal plate 64 that is not covered with the resist pattern 65b. As described above, many second recesses 35 are formed in the long metal plate 64 from the second surface 64b side.

  Thereafter, as shown in FIG. 13, the formed second recess 35 is covered with a resin 69 having resistance to the etching solution. That is, the second recess 35 is sealed with the resin 69 having resistance to the etching solution. In the example shown in FIG. 13, a film of resin 69 is formed so as to cover not only the formed second recess 35 but also the second surface 64b (resist pattern 65b).

  Next, as shown in FIG. 14, the second etching is performed on the long metal plate 64. In the second etching, the long metal plate 64 is etched only from the first surface 64a side, and the formation of the first recess 30 proceeds from the first surface 64a side. This is because the resin 69 having resistance to the etching solution is coated on the second surface 64b side of the long metal plate 64. Therefore, the shape of the second recess 35 formed in a desired shape is not impaired by the first etching.

  Etching due to etching is performed in the portion of the long metal plate 64 that is in contact with the etching solution. Therefore, erosion does not proceed only in the normal direction (thickness direction) of the long metal plate 64 but also proceeds in the direction along the plate surface of the long metal plate 64. As a result, as shown in FIG. 15, the etching proceeds in the normal direction of the long metal plate 64 so that the first recess 30 is connected to the second recess 35, and two adjacent holes 66a of the resist pattern 65a are connected. The two first recesses 30 formed at positions facing each other merge at the back side of the bridge portion 67a located between the two holes 66a.

  As shown in FIG. 16, the etching from the first surface 64a side of the long metal plate 64 further proceeds. As shown in FIG. 16, the joining portion 43 formed by joining two adjacent first concave portions 30 is separated from the resist pattern 65a, and erosion due to etching is caused by the metal plate in the joining portion 43 below the resist pattern 65a. The process proceeds in the 64 normal direction (thickness direction). As a result, the merging portion 43 sharpened toward one side along the normal direction of the vapor deposition mask is etched from one side along the normal direction of the vapor deposition mask, and as shown in FIG. Is done. Thereby, inclination-angle (theta) 1 which the wall surface 31 of the 1st recessed part 30 makes with respect to the normal line direction of a vapor deposition mask can be increased.

  In this way, the erosion of the first surface 64 a of the long metal plate 64 by etching proceeds in the entire region that forms the effective region 22 of the long metal plate 64. As a result, the maximum thickness Ta along the normal direction of the long metal plate 64 in the region that forms the effective region 22 becomes thinner than the maximum thickness Tb of the long metal plate 64 before etching.

  As described above, the etching from the first surface 64a side of the long metal plate 64 proceeds by a preset amount, and the second etching for the long metal plate 64 is completed. At this time, the 1st recessed part 30 is extended to the position which reaches the 2nd recessed part 35 along the thickness direction of the elongate metal plate 64, and, thereby, the 1st recessed part 30 and the 2nd recessed part 35 which are mutually connected. Through holes 25 are formed in the long metal plate 64.

  Thereafter, as shown in FIG. 17, the resin 69 is removed from the long metal plate 64. The resin film 69 can be removed by using, for example, an alkaline stripping solution. When an alkaline stripping solution is used, the resist patterns 65a and 65b are also removed simultaneously with the resin 69, as shown in FIG.

  The long metal plate 64 in which a large number of through holes 25 are formed in this way is conveyed to a cutting device (cutting means) 73 by conveyance rollers 72 and 72 that rotate while the long metal plate 64 is sandwiched. Is done. In addition, the supply core 61 described above is rotated through tension (pulling force) acting on the long metal plate 64 by the rotation of the transport rollers 72 and 72, and the long metal plate 64 is supplied from the wound body 62. It is like that.

  Thereafter, the long metal plate 64 in which a large number of recesses 61 are formed is cut into a predetermined length by a cutting device (cutting means) 73, whereby the sheet-like metal plate 21 in which a large number of through holes 25 are formed is obtained. can get.

  As described above, the vapor deposition mask 20 made of the metal plate 21 having a large number of through holes 25 is obtained. Here, according to the present embodiment, the first surface 21 a of the metal plate 21 is etched over the entire effective region 22. For this reason, the outer contour of the portion 43 where the tip edge 32 of the wall surface 31 of the two first recesses 30 formed on the first surface 21a side is reduced, and the thickness of the effective region 22 of the vapor deposition mask 20 is reduced, It can be a chamfered shape. Therefore, the above-described angle θ1 can be increased, thereby improving the utilization efficiency of the vapor deposition material and the positional accuracy of the vapor deposition.

  By the way, etching the first surface 21a of the metal plate 21 over the entire effective area 22 increases the difference between the degree of etching on the first surface 21a side and the degree of etching on the second surface 21b side. Become. That is, the released residual stress is imbalanced between the first surface 21a side and the second surface 21b side, and as a result, the metal plate 21, that is, the vapor deposition mask 20 is warped. Here, according to the present embodiment, as described above, the long metal plate 64 selected in advance based on the degree of warping of the sample 75 is used. For this reason, even if there is a difference in the degree of etching between the first surface 21a side and the second surface 21b side, the degree of warpage occurring in the vapor deposition mask 20 can be within an allowable range. . Therefore, according to the present embodiment, the thickness of the vapor deposition mask 20 is reduced, and the inclination angle θ1 of the wall surface 31 of the first recess 30 of the vapor deposition mask 20 is increased to improve the utilization efficiency of the vapor deposition material and the positional accuracy of the vapor deposition. It is possible to achieve both improvement, optimization of the contour, reduction of the warpage of the vapor deposition mask 20, and improvement of the yield of the production process of the vapor deposition mask 20. Therefore, the vapor deposition mask 20 having excellent characteristics can be provided stably.

(Vapor deposition method)
Next, a method for depositing a deposition material on the substrate 92 using the obtained deposition mask 20 will be described. First, as shown in FIG. 2, the vapor deposition mask 20 is brought into close contact with the substrate 92. At this time, the vapor deposition mask 20 is stretched on the frame 15 so that the surface of the vapor deposition mask 20 is parallel to the surface of the substrate 92. Here, according to the present embodiment, the long metal plate 64 previously selected based on the degree of warping of the sample 75 is used. For this reason, compared with the case where such a selection is not implemented, the degree of curvature of the vapor deposition mask 20 is uniformly reduced. Therefore, the deposition mask 20 can be held parallel to the substrate 92 by applying an appropriate tension to the deposition mask 20. That is, it is not necessary to apply high tension to the vapor deposition mask 20 so as to cause wrinkles in the vapor deposition mask 20 in order to correct the warp caused by the release of internal stress (residual stress). For this reason, the vapor deposition mask 20 can be sufficiently adhered to the substrate 92, whereby the vapor deposition material can be vapor-deposited on the substrate 92 with high positional accuracy. Therefore, when forming the pixel of an organic EL display device by vapor deposition, the dimensional accuracy and position accuracy of the pixel of the organic EL display device can be increased. This makes it possible to manufacture a high-definition organic EL display device.

  In the above-described embodiment, the plurality of effective regions 22 of the vapor deposition mask 20 are arranged at a predetermined interval along one direction parallel to one side of the vapor deposition mask 20 and are orthogonal to the one direction. An example in which a predetermined interval is also provided along the other direction is shown. However, the present invention is not limited to this, and as shown in FIG. 18, the vapor deposition mask 20 includes a plurality of effective regions 22 arranged in a line along one direction, and the vapor deposition mask apparatus 10 has a longitudinal direction thereof. You may make it have the some vapor deposition mask 20 arranged in the direction orthogonal to a direction (one direction) and attached to the flame | frame 15. The method for manufacturing such a vapor deposition mask 20 is not particularly limited. For example, you may manufacture the vapor deposition mask 20 using the elongate metal plate 64 which has the width | variety corresponding to the vapor deposition mask 20 shown in FIG. Alternatively, after forming a plurality of effective regions 22 along one direction and the other direction of the long metal plate 64, that is, the metal plate 21, the metal plate 21 is cut along its length direction, thereby being shown in FIG. The vapor deposition mask 20 may be produced.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

(Sample preparation)
First, by carrying out the rolling process and the annealing process described above on a base material made of an invar material, a wound body in which a long metal plate having a width of 500 mm and a thickness of t ₀ is wound (first 1 roll) was manufactured. Then, the 1st winding body was cut off over length 300mm, and the metal plate 63 shown to Fig.19 (a) was obtained. In FIG. 19A, the arrow D1 corresponds to the conveying direction in the rolling process, that is, the rolling direction, and the arrow D2 corresponds to the width direction in the rolling process.

  Next, as shown in FIG. 19B, a plurality of samples 75 were taken out from the metal plate 63. The sample 75 had a length of 170 mm and a width of 30 mm. The length direction of the sample 75 is a direction parallel to the arrow D1, and the width direction of the sample 75 is a direction parallel to the arrow D2. The number of samples 75 taken out from one metal plate 63 was 15. Etching was used as a method for taking out a plurality of samples 75 from the metal plate 63. Specifically, first, a resist pattern that covers the region to be the sample 75 and the outer frame portion 63 a of the metal plate 63 was provided on both the first surface side and the second surface side of the metal plate 63. Next, the metal plate 63 was etched from both the first surface side and the second surface side using the resist pattern as a mask. Thus, as shown in FIG. 19B, a through hole 63b was formed between the outer frame portion 63a of the metal plate 63 and the region of the metal plate 63 to be the sample 75. The etching was performed so that the connection portion 63c for connecting the outer frame portion 63a of the metal plate 63 and the sample 75 remains. The dimension of the connection part 63c is about 3 mm in length x 1 mm in width.

Next, as shown in FIG. 19C, the thickness of the etched region 75f of the sample 75 falls within the range of (1 / 2−8 / 100) × t ₀ to (1/2 + 8/100) × t _0. Until this time, the sample 75 was etched from the first surface 75a side of the sample 75 over the entire region 75f to be etched of the first surface 75a. Thereafter, the etched part 75 was removed from the metal plate 63 by cutting the connection part 63c. In addition, in order to prevent the influence of the distortion caused by the cutting from reaching the etched region 75f, precision scissors may be used as means for cutting the connection portion 63c.

Note that the through hole 63b is formed in the metal plate 63, and the thickness of the etched region 75f of the sample 75 is (1 / 2−8 / 100) × t ₀ to (1/2 + 8/100) × t _0. It may be carried out simultaneously by the same etching process.

(Calculation of sample curvature)
Next, in the same manner as in the case of the above-described inspection process, the curvature k (mm ⁻¹ ) of warpage in each etched sample 75 was sequentially obtained. Specifically, first, the sample 75 is placed on the placement surface 76a of the placement table 76 on which the hollow portion 76b is formed via the graph paper 77 so that the side surface 75c of the sample 75 is horizontal. did. Next, vibration was applied to the mounting surface 76a of the mounting table 76 until the state of warping of the sample 75 did not change visually. Thereafter, the distance x (mm) between the end portions in the length direction of the etched region 75f and the warp depth y (mm) of the etched region 75f of the sample 75 were read using the scale of the graph paper 77. Next, the curvature radius ρ corresponding to the warp of the etched region 75f of the sample 75 was calculated based on the following equation.
ρ = (y / 2) + (x ² / 8y)
Next, the curvature k of the curvature of the sample 75 was calculated based on the following formula.
k = 1 / ρ

The maximum value of the measurement result of the curvature k of the curvature of 15 samples 75 taken out from the first roll was 7.6 × 10 ⁻³ mm ⁻¹ .

(Evaluation of primary effects)
The vapor deposition mask was manufactured from the elongate metal plate of the 1st winding body using the manufacturing method of the above-mentioned vapor deposition mask. Next, the curl of the obtained vapor deposition mask was measured. The curl is the maximum value of the undulation of the vapor deposition mask in the vertical direction that appears when the vapor deposition mask is placed on a horizontal plane. As a result, the curl of the vapor deposition mask obtained from the long metal plate of the first wound body was 0.25 mm.

(Evaluation of secondary effects)
The vapor deposition material was vapor-deposited on the board | substrate using the vapor deposition mask produced from the elongate metal plate of the 1st winding body. In addition, the pattern of many through-holes formed in the used vapor deposition mask was a stripe pattern corresponding to the pixel density of 300 ppi. As the vapor deposition material, a green organic light emitting material that emits green light was used. Thereafter, the center coordinate position and the line width dimension of each of the plurality of green light emitting layers made of the organic light emitting material for green deposited on the substrate were measured. Moreover, the deviation | shift amount from a design value was calculated about each of the measured center coordinate position and line width dimension. And it was determined whether the deviation | shift amount was below an allowable value. At this time, the allowable value of the deviation amount of the center coordinate position was ± 4 μm, and the allowable value of the deviation amount of the line width dimension was ± 2 μm. As a result, the shift amount was less than the allowable value for both the center coordinate position and the line width dimension. That is, both the positional accuracy and dimensional accuracy of the vapor deposition material were good (OK).

  Table 1 shows the measurement results of the curvature of the sample taken out from the first winding body, and the evaluation results of the above-mentioned primary and secondary effects related to the vapor deposition mask made from the long metal plate of the first winding body. Show. In the same manner as in the case of the first winding body, the second winding body to the twentieth winding body were manufactured from the base material composed of the invar material. Further, in the same manner as in the case of the first winding body, with respect to the second winding body to the twentieth winding body, measurement of the curvature of the sample taken out from each winding body, and production from the long metal plate of each winding body. Evaluation of the above-mentioned primary effect and secondary effect regarding the evaporation mask was performed. The results are shown in Table 1.

As shown in Table 1, the curvatures of the samples taken out from the first roll to the tenth roll were all 0.008 mm ⁻¹ or less. Moreover, the curl of the vapor deposition mask produced from the long metal plate of the 1st roll to the 10th roll was 0.25 mm or less. Furthermore, in the vapor deposition using the vapor deposition mask produced from the long metal plate of the 1st roll to the 10th roll, both the positional accuracy and the dimensional accuracy of the vapor deposition material were good (OK).
On the other hand, the curvatures of the samples taken out from the 11th to 20th rolls exceeded 0.008 mm ⁻¹ . Moreover, the curl of the vapor deposition mask produced from the long metal plate of the 11th roll to the 20th roll was over 0.25 mm. Furthermore, in the vapor deposition using the vapor deposition mask produced from the long metal plate of the 11th roll to the 20th roll, all of the positional accuracy and dimensional accuracy of the vapor deposition material are defective (NG), Overall, everything was bad (NG). That is, the deviation from the design of the position and dimensions of the vapor deposition material deposited on the substrate was outside the allowable range.
From these facts, it can be said that a vapor deposition mask having good vapor deposition characteristics can be obtained by using a wound body in which the curvature of the sample taken out is 0.008 mm ⁻¹ or less.

DESCRIPTION OF SYMBOLS 20 Deposition mask 20a 1st surface of a vapor deposition mask 20b 2nd surface of a vapor deposition mask 21 Metal plate 21a 1st surface of a metal plate 21b 2nd surface of a metal plate 22 Effective area | region 23 Peripheral area | region 25 Through-hole 30 1st recessed part 31 Wall surface 35 Second concave portion 36 Wall surface 55 Base material 56 Rolling device 57 Annealing device 61 Core 62 Winding body 64 Long metal plate 64a First surface of long metal plate 64b Second surface of long metal plate 75 Sample 75a Sample 75a First surface 75b Sample second surface 75c, 75d Side surface 75f Area to be etched 76 Mounting table 76a Mounting surface 76b Hollow part 77 Graph paper

Claims (13)

A method for producing a metal plate used for producing a vapor deposition mask by forming a plurality of through holes,
The through hole of the vapor deposition mask is formed by etching the metal plate,
The method of manufacturing the metal plate is as follows:
Rolling a base material to obtain the metal plate having a thickness t ₀ ;
Annealing the metal plate to remove internal stress of the metal plate, and
The metal plate has a first surface and a second surface orthogonal to the thickness direction and facing each other,
When the sample taken out from the metal plate after the annealing step is etched, the curvature k of the sample warp after the etching is 0.008 mm ⁻¹ or less,
The curvature k is a length obtained by first removing the sample having a length of 170 mm and a width of 30 mm from the metal plate after the annealing step, and then excluding a region within 10 mm from both ends in the length direction of the sample. The sample is spread from the first surface side over the entire area to be etched until the thickness of the area to be etched having a length of 150 mm and a width of 30 mm falls within the range of 1/3 × t ₀ to 2/3 × t _0. Etching is performed, and then the etched sample is placed on a predetermined mounting table so that the side surface thereof is horizontal, and then the distance between end portions x ( mm) and the depth y (mm) of warpage of the etched region of the sample, and then the end-to-end distance x and the depth y are expressed by the following equation: k = / Ρ, ρ = (y / 2) + (x 2 / 8y)
A method for producing a metal plate, which is a value obtained by substituting for.   The method of manufacturing a metal plate according to claim 1, wherein the annealing step is performed while pulling the metal plate in a length direction.   The said annealing process is a manufacturing method of the metal plate of Claim 1 implemented in the state in which the said metal plate was wound up by the core.   4. The thermal expansion coefficient of the base material is a value equivalent to the thermal expansion coefficient of a substrate on which a vapor deposition material is formed through a vapor deposition mask manufactured from the metal plate. The manufacturing method of the metal plate of description.   The manufacturing method of the metal plate as described in any one of Claims 1 thru | or 4 with which the said base material is comprised from the invar material. A metal plate used for producing a vapor deposition mask by forming a plurality of through holes,
The metal plate has a thickness t ₀ , and the metal plate has a first surface and a second surface that are orthogonal to the thickness direction and face each other,
When the sample taken out from the metal plate is etched, the curvature k of the warp of the sample after etching is 0.008 mm ⁻¹ or less,
The curvature k is as follows. First, the sample having a length of 170 mm and a width of 30 mm is taken out of the metal plate, and then the length of the sample is 150 mm and the width is 30 mm excluding a region within 10 mm from both ends in the length direction. Until the thickness of the etched region is within the range of 1/3 × t ₀ to 2/3 × t ₀ , the sample is etched from the first surface side over the entire etched region, The etched sample is mounted on a predetermined mounting table so that the side surface thereof is horizontal, and then the distance x (mm) between the end portions of the sample in the length direction of the etched region and the sample The warp depth y (mm) of the region to be etched is measured, and then the distance x between the end portions and the depth y are expressed by the following equations k = 1 / ρ, ρ = (y / 2) ^(X 2 / 8y)
A metal plate that is a value obtained by substituting   The metal plate according to claim 6, wherein a thermal expansion coefficient of the metal plate is equal to a thermal expansion coefficient of a substrate on which a vapor deposition material is formed through a vapor deposition mask manufactured from the metal plate.   The metal plate according to claim 6 or 7, wherein the metal plate is made of an invar material. A method of manufacturing a vapor deposition mask comprising an effective area in which a plurality of through-holes are formed and a peripheral area located around the effective area,
Preparing a metal plate having a thickness t ₀ , the metal plate having a first surface and a second surface orthogonal to the thickness direction and facing each other;
The metal plate is etched from the first surface side, and a recess that defines the through hole is formed from the first surface side in the region of the metal plate that forms the effective region. A recess forming step,
When the sample taken out from the metal plate is etched, the curvature k of the warp of the sample after etching is 0.008 mm ⁻¹ or less,
The curvature k is as follows. First, the sample having a length of 170 mm and a width of 30 mm is taken out of the metal plate, and then the length of the sample is 150 mm and the width is 30 mm excluding a region within 10 mm from both ends in the length direction. Until the thickness of the etched region is within the range of 1/3 × t ₀ to 2/3 × t ₀ , the sample is etched from the first surface side over the entire etched region, The etched sample is mounted on a predetermined mounting table so that the side surface thereof is horizontal, and then the distance x (mm) between the end portions of the sample in the length direction of the etched region and the sample The warp depth y (mm) of the region to be etched is measured, and then the distance x between the end portions and the depth y are expressed by the following equations k = 1 / ρ, ρ = (y / 2) ^(X 2 / 8y)
A method for manufacturing a vapor deposition mask, which is a value obtained by substituting for.   10. The method for manufacturing a vapor deposition mask according to claim 9, wherein, in the recess forming step, the metal plate is etched over the entire area of the first surface from the first surface side. In the recess forming step, the metal plate is etched from the first surface side to the entire area of the first surface until the thickness thereof is within a range of 1/3 × t ₀ to 2/3 × t _0. The manufacturing method of the vapor deposition mask of Claim 10.   12. The thermal expansion coefficient of the metal plate is a value equivalent to the thermal expansion coefficient of a substrate on which a vapor deposition material is formed through a vapor deposition mask manufactured from the metal plate. The manufacturing method of the vapor deposition mask of description.   The manufacturing method of the vapor deposition mask as described in any one of Claims 9 thru | or 12 with which the said metal plate is comprised from the invar material.

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