JP6051876B2 - Metal mask and metal mask manufacturing method - Google Patents

Description

  The present invention relates to a metal mask, and more particularly, to a metal mask used for vapor deposition in a desired pattern. The present invention also relates to a manufacturing method for manufacturing the metal mask.

  Conventionally, a method of forming a thin film with a desired pattern using a vapor deposition mask including holes arranged in a desired pattern is known. In recent years, for example, when an organic material is vapor-deposited on a substrate at the time of manufacturing an organic EL display device, it is strongly desired to perform extremely high-definition patterning by vapor deposition.

  In general, such a deposition mask can be manufactured by forming holes in a metal plate by etching using a photolithography technique (for example, Patent Document 1). Moreover, when forming a hole in a metal plate by etching, there are a method of etching from both sides of the metal plate and a method of etching only from one side of the metal plate.

JP 2004-39319 A

  However, when a vapor deposition mask produced by etching is used, there is a problem that vapor deposition with an extremely fine pattern cannot be performed with high accuracy. An investigation of the cause of this failure confirmed the following.

  In etching using a photolithography technique, erosion starts from a region of the metal plate that is not covered with a resist film. Thereafter, the erosion does not proceed only in the thickness direction of the metal plate, but also proceeds in the direction along the plate surface of the metal plate. Accordingly, tapered holes are formed by etching. For this reason, when etching is performed from both sides of the metal plate 2, the overhanging portion 3 is formed in the hole 2 a except at the end portion in the thickness direction of the metal plate 2 as shown in FIG. 16. The overhang portion 3 forms a portion of the wall surface of the hole 2a that enters the innermost side of the hole 2a along the plate surface of the metal plate 2. Therefore, when the metal plate 2 is observed from the thickness direction, The projecting portion 3 defines an opening area of the hole 2a. When vapor deposition is performed using such a metal mask 1, the film thickness of the vapor deposition film 5 formed in the region corresponding to the back side of the protruding portion 3 of the substrate 4 is not stable. As a result, the edge of the vapor deposition pattern is blurred (the outline of the vapor deposition pattern is not clear). In the first place, it is difficult to control the position and cross-sectional shape of the overhang portion formed in the hole. From the above, when the metal plate is etched from both sides, it is not possible to perform deposition with an extremely fine pattern with high accuracy.

  On the other hand, when the metal plate is etched only from the upper surface, an etchant that has already been used for erosion and has a low erosion ability remains in the tapered hole formed by erosion. After that, when the hole of the metal plate reaches the lower surface, the etching solution remaining in the hole until then flows out from the lower surface, and into the hole in which a fresh etching solution having a high erosion ability is formed. Flows in. At this time, the liquid pressure increases in the lower region in the hole where the cross-sectional area (opening area) is small, and the lower region in the hole is eroded violently by the fresh etching solution. As a result, as in the case where etching is performed from both sides of the metal plate, a protruding portion is formed in the hole.

  Further, when the metal plate 6 is etched from only the lower surface through the resist film 7, when the tapered hole 6a formed by erosion penetrates the metal plate 6 as shown in FIG. In addition, the etching solution 8 may remain. As a result, erosion also proceeds from the upper surface of the metal plate by the remaining etching solution, and an overhang portion is formed in the hole as in the case of etching from both sides of the metal plate.

  Therefore, even when the metal plate is etched from only one side, the edge of the vapor deposition pattern is blurred (the outline of the vapor deposition pattern is not clear). In the first place, when the metal plate is etched from one surface side, the cross-sectional shape of the hole may be bent due to the pressure generated when the hole is penetrated and the etching solution starts to flow. In this case, it is difficult to accurately form the hole with a desired shape. This phenomenon becomes more prominent in the above-described metal mask for performing high-definition patterning. From the above, even when the metal plate is etched only from one surface, it is not possible to perform deposition with an extremely high-definition pattern with high accuracy.

  The present invention has been made in consideration of these points, and an object of the present invention is to provide a metal mask and a method of manufacturing the metal mask that enable extremely high-definition patterning.

According to the metal mask manufacturing method of the present invention, a metal plate having a first surface and a second surface opposite to the first surface is etched from the first surface side to have a curved wall surface and taper. Forming a recess to be formed from the first surface side;
Irradiating a laser beam in each recess to form a hole extending from the recess to the second surface, and
A method of manufacturing a metal mask by forming a through hole penetrating between the first surface and the second surface of the metal plate by the recess and the hole,
In the step of forming the hole, the hole is formed so as to connect to the curved wall surface of the recess and to taper from the first surface side toward the second surface side.

In the step of forming the recess in the method of manufacturing a metal mask according to the present invention, the recess is formed to have a curved shape in a cross section along the normal direction of the metal plate,
In the step of forming the hole, two surfaces that are inclined with respect to both the plate surface of the metal plate and the normal direction of the metal plate at a connection position between the hole and the curved wall surface of the recess. Connected, a circumferential step may be formed.

A metal mask according to the present invention comprises a metal plate having a first surface and a second surface opposite to the first surface,
A plurality of through holes are formed in the metal plate,
The outline of each through hole in the cross section along the normal direction of the metal plate is
The metal plates are arranged facing each other in a direction parallel to the plate surface, and each extends from the first surface side to a connection position in the middle between the first surface and the second surface. A pair of first portions that are closer to each other in a direction parallel to the plate surface of the metal plate as they go from the first surface side to the second surface side along the normal direction of the metal plate. A pair of first parts to be
A pair of second parts, which are arranged facing each other in a direction parallel to the plate surface of the metal plate, each connected to the first part on the corresponding side and extending from the connection position to the second surface. A pair of firsts approaching each other in a direction parallel to the plate surface of the metal plate as it goes from the first surface side to the second surface side along the normal direction of the metal plate. 2 parts,
In the cross section along the normal direction of the metal plate, the first portion has a curved shape.

  In the connection position in each through hole in the metal mask according to the present invention, two surfaces inclined with respect to both the plate surface of the metal plate and the normal direction of the metal plate are connected to form a circumferential step. May be.

  In the cross section along the normal direction of the metal plate in the metal mask according to the present invention, an angle formed by a line segment connecting both ends of the first portion with respect to the normal direction of the metal plate is the second portion. A line segment connecting both end portions may be larger than an angle formed with respect to a normal direction of the metal plate.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the metal mask which can perform very high-definition patterning, and the said metal mask is provided.

FIG. 1 is a schematic perspective view showing an example of a metal mask device including a metal mask according to an embodiment of the present invention. FIG. 2 is a view for explaining a method of vapor deposition using the metal mask apparatus shown in FIG. FIG. 3 is a partial plan view showing the metal mask shown in FIG. FIG. 4 is a cross-sectional view taken along a line IV-IV in FIG. FIG. 5 is a diagram for explaining the operation of the metal mask. FIG. 6 is a diagram for explaining an example of a method for manufacturing the metal mask shown in FIG. FIG. 7 is a diagram for explaining a method of forming a resist pattern on a metal sheet. FIG. 8 is a diagram for explaining a method of etching a metal sheet. FIG. 9 is a diagram for explaining a method of irradiating a sheet-like metal sheet with laser light. FIG. 10 shows a metal mask in which the wall surfaces of adjacent through-holes are connected, (a) is a partial plan view, and (b) is a cross section taken along line AA in FIG. 10 (a). FIG. FIG. 11 is a partial plan view showing another arrangement example of the through holes. FIG. 12 is a partial plan view showing another example of patterning performed on the glass substrate. FIG. 13 is a partial plan view showing still another example of patterning performed on a glass substrate. FIG. 14 is a partial plan view of a metal mask for red vapor deposition material that can be used for the glass substrate shown in FIG. FIG. 15 is a view corresponding to FIG. 6 and illustrating a modified example of the method for manufacturing the sheet with the vapor deposition mask. FIG. 16 is a diagram corresponding to FIG. 5 for explaining a method of vapor deposition using a metal mask made of a metal plate etched from both sides. FIG. 17 is a view corresponding to FIG. 8 for explaining a method of manufacturing a metal mask by etching a metal plate from the lower surface.

  Hereinafter, an embodiment of a metal mask and a method of manufacturing a metal mask according to the present invention will be described with reference to FIGS. Here, FIG. 1 to FIG. 9 are diagrams for explaining an embodiment of the present invention. In the following embodiments, a metal mask for vapor deposition used for patterning an organic light emitting material on a glass substrate in a desired pattern when manufacturing an organic EL display device, and a method for manufacturing the metal mask are taken as an example. I will explain. However, the present invention is not limited to such an application, and the present invention can be applied to a metal mask used for various purposes and a method for manufacturing the metal mask.

  First, an example of a metal mask apparatus including a metal mask that can be manufactured by the method of manufacturing a metal mask according to the present embodiment will be described mainly with reference to FIGS. Here, FIG. 1 is a perspective view showing an example of a metal mask device including a metal mask according to the present embodiment, and FIG. 2 is a diagram for explaining a method of using the metal mask device shown in FIG. .

  As shown in FIGS. 1 to 4, the metal mask device 10 according to the present embodiment includes a metal mask 20 made of a rectangular metal sheet, and a frame 15 attached to the periphery of the metal mask 20. ing. The metal mask 20 includes a metal plate 21 having a first surface 21a and a second surface 21b opposite to the first surface 21a. The metal plate 21 has a space between the first surface 21a and the second surface 21b. A plurality of through-holes 25 extending therethrough are formed. As shown in FIG. 2, the metal mask device 10 is supported in the vapor deposition device 40 so that the metal mask 20 faces the glass substrate 42. And the metal mask 20 and the glass substrate 42 are urged | biased by the magnet not shown so that it may contact | adhere. In the vapor deposition apparatus 40, a crucible 44 for accommodating a vapor deposition material (for example, an organic light emitting material) 48 and a heater 46 for heating the crucible 44 are disposed below the glass substrate 42 with the metal mask apparatus 10 interposed therebetween. Has been. The vapor deposition material 48 in the crucible 44 is vaporized or sublimated by heating from the heater 46 and adheres to the surface of the glass substrate 42. As described above, a large number of through holes 25 are formed in the metal plate 21, and the vapor deposition material 48 adheres to the glass substrate 42 through the through holes 25. As a result, the vapor deposition material 48 is formed on the surface of the glass substrate 42 in a desired pattern corresponding to the position of the through hole 25 of the metal plate 21.

  As shown in FIG. 1, in the present embodiment, the metal 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 metal mask 20 includes a perforated region 22 in which the through hole 25 is formed and a non-perforated region 23 in which the through hole 25 is not formed and occupies a region surrounding the perforated region 22. Have. As shown in FIG. 1, each of the perforated regions 22 has a substantially rectangular shape in a plan view, more precisely, a substantially rectangular shape in a plan view.

  In the present embodiment, the plurality of perforated regions 22 are arranged at a predetermined interval along one direction parallel to one side of the metal mask 20 (metal plate 21), and are orthogonal to the one direction. They are arranged at predetermined intervals along the direction. In the present embodiment, one perforated region 22 corresponds to one organic EL display device. That is, according to the metal mask apparatus 10 (metal mask 20) shown in FIG. 1, multi-surface deposition is possible.

  As shown in FIGS. 1 and 3, the plurality of through holes 25 formed in each perforated region 22 are arranged side by side at equal intervals in one direction in the perforated region 22. . In addition, each through hole 25 is elongated from one end of the perforated region 22 to the other end in parallel with the other direction orthogonal to the one direction.

  The through hole 25 formed in the metal plate 21 will be described in more detail with reference to FIG. 3 and FIG. 3 is a partial plan view showing the metal mask 20 from the first surface 21a side, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. As shown in FIG. 4, the plurality of through holes 25 extend between the first surface 21a and the second surface 21b. Moreover, each penetration in the cross section along the plate surface of the metal plate 21 in each position along the normal line direction nd of the metal plate 21 toward the 2nd surface 21b from the 1st surface 21a of the metal plate 21 which consists of a sheet form. The cross-sectional area of the hole 25 gradually decreases. In particular, in the illustrated example, the cross-sectional area of each through-hole 25 continues to change so as to decrease from the first surface 21 a to the second surface 21 b of the metal plate 21.

  In this specification, the “plate surface (sheet surface)” corresponds to the planar direction of the target plate-like member when the target plate-like or band-like member is viewed as a whole and as a whole. Refers to the surface. In the present embodiment, the first surface 21 a and the second surface 21 b of the metal plate 21 are parallel to the plate surface of the metal plate 21.

  As shown in FIG. 4, the outline of each through hole 25 in the cross section along the normal direction nd orthogonal to the plate surface of the metal plate 21, in other words, along the normal direction nd orthogonal to the plate surface of the metal plate 21. In the cross section, the shape of the wall surface of each through-hole 25 (the line segment defining the wall surface) is arranged to face in the direction parallel to the plate surface of the metal plate 21, and A pair of first portions 28 extending to the connection position 26 in the middle between the first surface 21a and the second surface 21b, and arranged in a direction parallel to the plate surface of the metal plate 21, And a pair of second portions 29 connected to the corresponding first portion 28 and extending from the connection position 26 to the second surface 21b.

  As shown in FIG. 4, the pair of first portions 28 approach each other as they go from the first surface 21a side to the second surface 21b side. That is, the pair of first portions 28 extends along a direction parallel to the plate surface of the metal plate 21 from the first surface 21 a side toward the second surface 21 b side along the normal direction nd of the metal plate 21. And approach each other. From another point of view, the pair of first portions 28 has a tapered shape that tapers from the first surface 21a side toward the second surface 21b side.

  Furthermore, in the cross section along the normal direction nd of the metal plate 21, the first portion 28 has a curved shape. The cross-sectional contour of the illustrated first portion 28 is such that the inclination angle with respect to the normal direction nd of the metal plate 21 at any point on the first portion 28 is first along the normal direction nd than the point. It is larger than the inclination angle at the point on the surface 21a side. That is, the inclination angle with respect to the normal direction nd of the first portion 28 gradually increases from the first surface 21a toward the second surface 21b. In this case, in a cross section along the normal direction nd of the metal plate 21, a line segment connecting both end portions of the first portion 28, that is, a line segment L1 connecting one end portion on the first surface 21a side and the connection position 26 is shown. On the other hand, the first portion 28 is located on the second surface 21b side. Note that the shape of the first portion 28 is defined by the isotropic property of erosion by the etching solution in the manufacturing method described later.

  On the other hand, as shown in FIG. 4, the pair of second portions 29 approach each other as they go from the first surface 21 a side to the second surface 21 b side. That is, the pair of second portions 29 are arranged in a direction parallel to the plate surface of the metal plate 21 toward the second surface 21b from the first surface 21a side along the normal direction nd of the metal plate 21. Approach. From another point of view, the pair of second portions 29 has a tapered shape that tapers from the first surface 21a side toward the second surface 21b side. According to such a form, unlike the metal mask described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-39319), the opening area of the through hole 25 (the through hole 25 along the plate surface of the metal plate 21). The area of the opening area) is not the position between the first surface 21a and the second surface 21b along the normal direction of the metal plate 21, but is the smallest on the second surface 21b. Therefore, when vapor deposition is performed on the glass substrate 42 using the vapor deposition mask 20 described here, the vapor deposition material 48 is not dependent on the traveling direction of the glass substrate 42 as shown in FIG. Adhering to a region facing the through-hole 25 on the second surface 21b of the metal plate 21 and effectively adhering to a region on the glass substrate 42 that is outside the region is effectively suppressed. . Therefore, compared with the metal mask described in Patent Document 1, it is possible to perform deposition with a high-definition pattern with high accuracy.

  In the present embodiment, the second portion 29 is linear in the cross section along the normal direction nd of the metal plate 21. That is, the inclination angle with respect to the normal direction nd is constant at an arbitrary point on the second portion 29.

  As shown in FIG. 4, at the connection position 26 in each through hole 25, two surfaces inclined with respect to both the plate surface of the metal plate 21 and the normal direction nd of the metal plate 21 are connected, and the circumferential shape A step 27 is formed. The circumferential step 27 is formed in a protrusion, protrudes toward the center of the through hole 25 and extends in a circumferential shape. And since the 1st part 28 is connected to the 2nd part 29 in the state inclined with respect to both the plate | board surface of the metal plate 21, and the normal line direction nd of the metal plate 21, the wall surface of the 1st part 28 is a connection position. The flat side parallel to the plate surface of the metal plate 21 is not included on the 26th side. When the wall surface of the first portion 28 includes a flat portion, the thickness between the flat portion and the second surface 21b is reduced, and the risk of damaging the metal mask 20 during handling of the metal mask 20 increases. . Therefore, when two surfaces inclined with respect to both the plate surface of the metal plate 21 and the normal direction nd of the metal plate 21 are connected at the connection position 26, the metal mask 20 is handled during handling of the metal mask 20. The risk of breakage can be reduced. Further, the protrusion formed at the connection position 26 functions like a reinforcing beam, and can effectively regulate the torsion and distortion of the metal mask 20.

  In the illustrated embodiment, as described above, the inclination angle of the first portion 28 with respect to the normal direction nd gradually increases from the first surface 21a toward the second surface 21b. The second portion 29 has a constant inclination angle with respect to the normal direction nd at any point on the second portion 29. Therefore, two inclined surfaces are connected at different inclination angles, and the above-described circumferential step 27 is formed.

  Here, FIG. 5 shows a state in which the deposition material 48 is deposited on the glass substrate 42 using the metal mask device 10. As shown in FIG. 5, when the metal mask device 10 is housed in the vapor deposition device 40, the first surface 21 a of the metal plate 21 is positioned on the crucible 44 side holding the vapor deposition material 48, and the second surface of the metal plate 21. 21 b faces the glass substrate 42. That is, as shown in FIG. 5, the vapor deposition material 48 adheres to the glass substrate 42 through the through hole 25 whose cross-sectional area is gradually reduced. As shown in FIG. 5, the vapor deposition material 48 not only moves along the normal direction of the glass substrate 42 from the crucible 44 toward the glass substrate 42, but is also greatly inclined with respect to the normal direction of the glass substrate 42. It may move in the direction. At this time, if the cross-sectional shape of the through hole 25 has an outline indicated by a dotted line in FIG. 5, the deposition material 48 that moves obliquely does not adhere to the metal mask 20 and reach the glass substrate 42. As a result, it becomes difficult to adhere the vapor deposition material 48 to the glass substrate 42 by a desired amount, the use efficiency of the vapor deposition material 48 is lowered, and the edge of the vapor deposition pattern is blurred.

That is, in order to increase the utilization efficiency (deposition efficiency: rate of adhesion to the glass substrate 42) of the vapor deposition material to save expensive vapor deposition material and perform high-definition patterning, the sheet surface of the metal plate 21 is used. 4 and 5 orthogonal to each other, a straight line L1 connecting the end of the first portion 28 on the first surface 21a side and the end of the first portion 28 on the second surface 21b side, and the normal line of the metal plate 21 It is better that the angle θ ₁ (see FIG. 4) formed by the direction nd is larger. However, the ratio of the vapor deposition material that moves toward the glass substrate 42 so as to form a large angle with respect to the perpendicular to the glass substrate 42 is small. And when the present inventors confirmed, if the angle (theta) ₁ which the above-mentioned straight line L1 makes with respect to the normal line direction nd was 30 degrees or more, the utilization efficiency of vapor deposition material became a sufficient value.

Next, the relationship between the first portion 28 and the second portion 29 will be described in detail. First, as shown in FIG. 4, an angle formed by a line segment L <b> 1 connecting both ends of the first portion 28 with respect to the normal direction nd of the metal plate 21 in a cross section along the normal direction nd of the metal plate 21. θ ₁ is preferably larger than an angle θ ₂ formed by a line segment L 2 connecting both ends of the second portion 29 with respect to the normal direction nd of the metal plate 21. According to such a configuration, the vapor deposition material 48 that goes toward the region surrounded by the wall surface that defines the second portion 29 is less likely to be blocked by the wall surface that defines the first portion 28. In addition, the area of the first surface 21a of the metal plate 21 is reduced, so that the amount of the vapor deposition material 48 attached to the first surface 21a can be reduced. As a result, the deposition material 48 can be easily attached to the glass substrate 42 by a desired amount, and the utilization efficiency of the deposition material 48 can be further increased.

  As described above, the first portion 28 has a curved shape in the cross section along the normal direction nd of the metal plate 21. In this case, the metal mask 20 is thinner and lighter than the case where the first portion is formed in a straight line, that is, formed so as to coincide with the line segment L1 connecting both ends of the first portion. Can be realized. On the other hand, the wall surface of the through hole 25 constitutes a rib, and the resistance to deformation is maintained. For this reason, compared with the case where the 1st part is formed in the shape of a straight line, the bending of the metal mask 20 does not change substantially. Therefore, according to such an embodiment, it is possible to obtain the effect of preventing the metal mask 20 from being bent while realizing the reduction in thickness and weight of the metal mask 20.

  By the way, as described above, when the vapor deposition material 48 is attached to the glass substrate 42, the metal mask 20 and the glass substrate 42 are urged by a magnet (not shown) so as to be in close contact with each other. However, the second surface 21b of the metal plate 21 and the second surface 21b of the metal plate 21 are caused by factors such as fine irregularities on the surface of the metal plate 21 or the surface of the glass substrate 42 and foreign matters inevitably mixed between the metal mask 20 and the glass substrate 42. A slight gap may be formed between the glass substrate 42. When a gap is generated between the second surface 21 b of the metal plate 21 and the glass substrate 42, the vapor deposition material 48 that moves obliquely with respect to the normal direction of the glass substrate 42 is separated from the through hole 25 in the glass substrate 42. There is a risk of adhering not only to the directly facing area but also to the surrounding area. As a result, the edge of the vapor deposition pattern is blurred.

  In this regard, as shown in FIG. 4, the metal mask 20 of the present embodiment extends along at least a part of the peripheral edge of the through hole 25 on the second surface 21b of the metal plate 21, and the second surface 21b. An extending piece 24 extending outward in the normal direction nd of the metal plate 21 from the peripheral edge of the upper through hole 25 is provided. According to such a form, the gap between the second surface 21 b of the metal plate 21 of the metal mask 20 and the glass substrate 42 is closed by the extending piece 24 in a state where the metal mask 20 faces the glass substrate 42. be able to. Thereby, the vapor deposition material 48 that moves obliquely with respect to the plate surface of the glass substrate 42 adheres to the periphery of the region on the glass substrate 42 that directly faces the through hole 25, and the edge of the vapor deposition pattern is blurred. Can be effectively suppressed. For this reason, vapor deposition with a high-definition pattern can be performed accurately.

  In the illustrated example, the extending piece 24 surrounds the periphery of the through hole 25 on the second surface 21b. More specifically, the extending piece 24 extends circumferentially along the entire circumference of the peripheral edge of the through hole 25 on the second surface 21b. According to such a configuration, the extension piece 24 can block the gap between the second surface 21 b of the metal plate 21 of the metal mask 20 and the glass substrate 42 along the entire circumference of the peripheral edge of the through hole 25. it can. Thereby, it can suppress more effectively that the edge of a vapor deposition pattern blurs.

  As described above, the extending piece 24 extends circumferentially over the entire circumference of the peripheral edge of the through hole 25 on the second surface 21b. Therefore, in the cross section of FIG. 4 and FIG. 5 along the normal direction nd of the metal plate 21, a pair of the extended pieces 24 appear in a direction parallel to the plate surface of the metal plate 21. 4 and 5, the pair of third portions 24 a forming the extension piece 24 are separated from the metal plate along the direction of the normal of the metal plate 21 as it goes outward. As you approach each other. That is, in the cross section along the normal direction nd of the metal plate 21, the extension piece 24 extends along the normal direction of the metal plate 21 from the position of the peripheral edge of the through hole 25 on the second surface 21 b of the metal plate 21. It extends to the outer side (side away from the metal plate) and toward the center of the through hole 25 along the plate surface of the metal plate 21. Further, in the cross section along the normal direction nd of the metal plate 21, the thickness of the extended piece 24, more precisely, the thickness along the direction perpendicular to the longitudinal direction of the extended piece 24 is the metal plate 21. The thickness gradually decreases from the base end connected to the tip toward the tip farthest from the metal plate.

  Further, the extending piece 24 is formed to be thin along the entire circumference of the peripheral edge of the through hole 25 on the second surface 21b. In this case, if the metal plate 21 and the glass substrate 42 are to be brought into close contact with each other by the magnetic force of the magnet, the extension piece 24 may come into contact with the glass substrate 42 and be further bent somewhat. For this reason, the adhesiveness of the metal mask 20 and the glass substrate 42 improves further, and vapor deposition with a high-definition pattern can be performed more accurately. Here, the thickness of the extension piece 24 refers to the thickness of the base end portion of the extension piece 24 along the second surface 21 b in the cross section along the normal direction nd of the metal plate 21.

  As an example, the extension piece 24 has a thickness of 1 μm or more and 5 μm or less. When the extension piece 24 is formed to have a thickness of 5 μm or more, the extension piece 24 has high rigidity, and the extension piece 24 is effectively bent when the metal plate 21 and the glass substrate 42 are brought into close contact with each other. I can't do that. On the other hand, if the thickness of the extension piece 24 is 1 μm or less, the strength of the extension piece 24 decreases, and the extension piece 24 is damaged when the metal plate 21 and the glass substrate 42 are brought into close contact with each other. There is a risk that.

  Further, the height of the extended piece 24, in other words, the protruding amount from the second surface 21b of the extended piece 24 along the normal direction nd of the metal plate 21 is, for example, 1 μm or more and 5 μm or less. The If the height of the extended piece 24 is 5 μm or more, for example, the extended piece 24 prevents the metal mask 20 and the glass substrate 42 from being in close contact with each other, and the gap between the metal mask 20 and the glass substrate 42 is effectively reduced. There is a possibility that it cannot be buried. As a result, there is a possibility that vapor deposition with a high-definition pattern cannot be performed. On the other hand, if the height of the extended piece 24 is 1 μm or less, the gap between the metal mask 20 and the glass substrate 42 cannot be filled, and vapor deposition with a high-definition pattern may not be performed.

  According to such an extended piece 24, when trying to bring the metal plate 21 and the glass substrate 42 into close contact with each other, the extended piece 24 is further provided on the through hole 25 side in a direction parallel to the plate surface of the metal plate 21. Bends to extend. For this reason, the vapor deposition material 48 that moves obliquely with respect to the normal direction of the glass substrate 42 wraps around not only the region of the glass substrate 42 that faces the through hole 25 but also the peripheral region thereof, and the glass substrate 42. It can suppress more effectively that it adheres to.

  In the present embodiment, the extension piece 24 is formed integrally with the metal plate 21. According to such a form, the extension piece 24 and the metal plate 21 can be accurately connected. Specifically, the extended piece 24 is a return formed with laser light irradiation in the manufacturing method described later. The mechanism by which the extended piece 24 is formed as a return will be described later.

  As described above, in the present embodiment, the through holes 25 are arranged at equal intervals in each perforated region 22. As an example, when the metal mask 20 (metal mask device 10) is used to produce a display (about 2 to 5 inches) such as a mobile phone or a digital camera, the arrangement pitch P of the through holes 25 (see FIG. 4) is 58 μm (440 ppi) or more and 254 μm (100 ppi) or less. When color display is to be performed, the metal mask 20 (metal mask device 10) and the glass substrate 42 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. Further, when the metal mask 20 (metal mask device 10) is used for manufacturing a display of a mobile phone, the width (slit width) W along the arrangement direction (one direction described above) of each through-hole 25 is 28 μm. The thickness may be about 84 μm or less.

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

  The metal mask device 10 is held inside the vapor deposition device 40 that is in a high temperature atmosphere. Therefore, the metal mask 20 and the frame 15 are preferably made of the same material having a low coefficient of thermal expansion in order to prevent the deposition frame from being bent or generating thermal stress. As such a material, for example, a 36% Ni invar material can be used.

  As described above, according to the present embodiment, the pair of first portions in which the through holes 25 formed in the metal plate 21 approach each other from the first surface 21a side toward the second surface 21b side. 28 and a pair of second portions 29 each connected to the corresponding first portion 28 and approaching each other from the first surface 21a side toward the second surface 21b side. . According to such a form, the vapor deposition material 48 that moves in a direction greatly inclined from the normal direction of the glass substrate 42 can be sufficiently adhered to the glass substrate 42. Thereby, the utilization efficiency of the vapor deposition material 48 can be improved significantly. In addition, the vapor deposition film is not formed with an unstable film thickness in the region on the glass substrate 42 that is the periphery of the region facing the through hole 25 on the second surface 21 b of the metal plate 21. Therefore, according to the metal mask 20 of the present embodiment, vapor deposition with a high-definition pattern can be accurately performed with a desired thickness.

  In particular, in the organic EL display device, it is strongly desired to pattern the expensive vapor deposition material 48 on the substrate 42 with a high-definition pattern. For this reason, the metal mask 20 of this Embodiment is especially suitable for the vapor deposition mask used in order to manufacture an organic EL display apparatus.

  Further, according to the present embodiment, the first portion 28 has a curved shape in the cross section along the normal direction nd of the metal plate 21. In this case, the metal mask 20 can be made thinner and lighter than when the first portion is formed linearly. On the other hand, the wall surface of the through hole 25 constitutes a rib, and the resistance to deformation is maintained. For this reason, compared with the case where the 1st part is formed in the shape of a straight line, the bending of the metal mask 20 does not change substantially. Therefore, according to such an embodiment, it is possible to obtain the effect of preventing the metal mask 20 from being bent while realizing the reduction in thickness and weight of the metal mask 20.

  By the way, when the thickness of the metal plate 21 is reduced, the metal mask 20 may be damaged during the handling of the metal mask 20, for example, during the transport of the metal mask 20. In particular, in manufacturing the organic EL display device, for example, in the metal mask 20 used for patterning the vapor deposition material 48 on the glass substrate 42 in a desired pattern, the plurality of through holes 25 elongated in the same direction have a short pitch. May be arranged side by side. When handling such a metal mask 20, the force acting on the metal mask 20 cuts between the holes of the metal mask 20, or the portions extending linearly between the holes are Problems such as getting tangled easily occur. For this reason, for example, it was extremely difficult to perform patterning using a metal plate 21 having a thickness of less than 30 μm.

  In this regard, as an attempt to reduce the thickness of a conventional vapor deposition mask, for example, Japanese Patent Application Laid-Open No. 04-236758 describes the use of a vapor deposition mask made of silicon. In this vapor deposition mask, the peripheral region of the silicon plate is formed to a thickness of 180 μm, and a flat portion parallel to the sheet surface having a thickness of 20 μm is formed in the central region surrounded by the peripheral region. And the through-hole which consists of a desired vapor deposition pattern is formed in this flat part. However, silicon is much weaker than metal. Furthermore, since the through-hole which consists of a desired vapor deposition pattern is formed in the flat part which consists of thickness 20 micrometers, the intensity | strength of the silicon plate of the flat part vicinity is still lower. For this reason, there is an extremely high possibility that the vapor deposition mask is damaged from the vicinity of the flat portion during the handling of the vapor deposition mask.

  On the other hand, according to the present embodiment, the metal mask 20 is made of a metal whose strength is considerably higher than that of silicon. The pair of first portions 28 approach each other as they go from the first surface 21 a side to the second surface 21 b side, and at the connection position 26 in each through hole 25, the plate surface of the metal plate 21 and Two surfaces inclined with respect to both the normal direction nd of the metal plate 21 are connected. For this reason, compared with the case where a 1st part contains the flat part parallel to a sheet surface, thickness can be ensured large between the 1st part 28 and the 2nd surface 21b. Due to the combination of these features, the metal mask 20 of the present embodiment is extremely less likely to be damaged during handling than the vapor deposition mask described in the above-mentioned patent document.

  Next, a method for manufacturing the metal mask 20 and the vapor deposition mask apparatus 10 will be described mainly with reference to FIGS. Among these, FIG. 6 is a figure for demonstrating the manufacturing method of a vapor deposition mask generally, FIG. 7 is a figure for demonstrating the method of forming a resist pattern in metal sheets, FIG. It is a figure for demonstrating the method to etch a metal sheet.

  As shown in FIG. 6 to FIG. 9, the vapor deposition mask manufacturing method according to the present embodiment has a first surface 34 a and a second surface 34 b opposite to the first surface 34 a and has a metal sheet extending in a strip shape. 34, a step of performing etching using a photolithographic technique on the metal sheet 34 to form a tapered recess 61 having a curved wall surface from the side of the first surface 34a, and each recess 61 And irradiating a laser beam therein to form a hole 62 extending from the recess 61 to the second surface 34b. Each step will be described in more detail below.

  As shown in FIG. 6, in the present embodiment, a wound body 29 in which a metal sheet 34 is wound around a supply core 31 is prepared. Then, when the supply core 31 rotates and the wound body 29 is rewound, a metal sheet 34 extending in a strip shape is supplied as shown in FIG. The metal sheet 34 is formed with the through hole 25 to form the metal mask 20. Therefore, as described above, the metal sheet 34 is made of, for example, 36% Ni invar material. However, the sheet is not limited thereto, and a sheet made of stainless steel, copper, iron, or aluminum can be used as the metal sheet 34.

  The supplied metal sheet 34 is subjected to an etching process by an etching apparatus (etching means) 50. Specifically, first, a negative photosensitive resist material is applied on the first surface 34a of the metal sheet 34, and a resist film 36 is formed on the first surface 34a. Next, a glass dry plate 37 is prepared in which light is not transmitted to a region to be removed of the resist film 36, and the glass dry plate 37 is disposed on the resist film 36.

  Thereafter, as shown in FIG. 7, the resist film 36 is exposed through a glass dry plate 37, and the resist film 36 is further developed. As described above, a resist pattern (simply referred to as a resist) 35 is formed on the first surface 34 a of the metal sheet 34.

  Note that a region of the glass dry plate 37 facing the resist film 36 to be removed may be black, and visible light may be used as exposure light. In this case, the visible light is absorbed by the black portion, so that light does not enter the region to be removed of the resist film 36 and the resist film 36 is not photocured on the metal sheet 34. On the other hand, light enters a region where the resist film 36 should not be removed, and the resist film 36 in the region is photocured on the metal sheet 34. The resist film 36 that has not been photocured is removed by, for example, hot water washing.

  Next, as shown in FIG. 8, using the resist pattern 35 formed on the metal sheet 34 as a mask, the metal sheet 34 is etched from the first surface 34a side by an etching solution (for example, ferric chloride solution) 38. To do. In the present embodiment, the etching solution 38 is directed from the lower nozzle 51 of the etching apparatus 50 disposed below the conveyed metal sheet 34 toward the first surface 34 a of the metal sheet 34 through the resist pattern 35. Is injected. Then, as shown by a dotted line in FIG. 8, erosion by the etching solution starts in a region of the metal sheet 34 that is not covered with the resist pattern 35. This erosion by the etching solution is performed in a portion of the metal sheet 34 that is in contact with the etching solution. Therefore, erosion does not proceed only in the thickness direction of the metal sheet 34 but also proceeds in the direction along the sheet surface of the metal sheet 34. In addition, in the present embodiment, the flow rate and spray time of the etching solution 38 sprayed from the lower nozzle 51 can be controlled. Accordingly, by appropriately controlling the flow rate of the jetted etching solution 38 and the jetting time, the degree of erosion in the thickness direction of the metal sheet 34 and the erosion in the direction along the sheet surface of the metal sheet 34 are adjusted. . As described above, erosion by the etching solution proceeds from the first surface 34a to the second surface 34b side of the metal sheet 34, so that the concave portion 61 having a curved wall surface and tapered is obtained. It is done. In particular, in the present embodiment, erosion by the etching solution is isotropically performed in a portion of the metal sheet 34 that is in contact with the etching solution, and each recess 61 is in the normal direction of the metal sheet 34. It is formed to have a curved shape in the cross section along. And this recessed part 61 does not extend to the 2nd surface 34b of the metal sheets 34, but leaves | separates the said 2nd surface 34b and predetermined spacing. Moreover, the recessed part 61 is formed so that it may elongate along the other direction orthogonal to the sequence direction.

  Thereafter, the resist pattern 35 on the metal sheet 34 is removed, and the metal sheet 34 is washed with water.

  The metal sheet 34 in which a large number of recesses 61 are formed in this way is conveyed to a cutting device (cutting means) 53 by a pair of conveying rollers 52, 52 that rotates while holding the metal sheet 34. The It is to be noted that the supply core 31 described above is rotated via the tension (pulling force) acting on the metal sheet 34 by the rotation of the conveying rollers 52 and 52 so that the metal sheet 34 is supplied from the wound body 29. It has become.

  A sheet-like metal sheet 64 is obtained by cutting the metal sheet 34 with a large number of recesses 61 into a predetermined length by a cutting device (cutting means) 53.

  Next, as shown in FIG. 9, the sheet-like metal sheet 64 is held by the holding unit 73 of the laser processing apparatus 70 without wrinkles or sagging. As this laser processing apparatus 70, a laser processing apparatus 70 known per se that can be used for forming a through hole having a predetermined pattern in a metal mask is used. Examples of the laser used in the laser processing apparatus 70 include a YAG laser, a carbon dioxide laser, a semiconductor laser, and the like, which are appropriately selected according to the material of the metal sheet 34, the depth of the hole 62, and the like. The laser processing apparatus 70 according to the present embodiment can irradiate a laser beam generated from a variable output laser oscillator from a laser irradiation lens 72 with a predetermined spot diameter.

  Laser light is irradiated from the laser irradiation lens 72 of the laser processing apparatus 70 into each concave portion 61 of the sheet-like metal sheet 64, and the laser light is moved along the longitudinal direction of the concave portion 61. By irradiating the laser beam, a part of the metal sheet 64 between each recess 61 and the second surface 34b is melted, and the melted part is scattered or removed by the assist gas. Thereby, a hole 62 extending from the recess 61 to the second surface 34 b is formed in the sheet-like metal sheet 64. In particular, the metal sheet 64 melts much on the concave portion 61 side, and the amount of melting decreases toward the second surface 34b side. As a result, the hole 62 is formed in a tapered shape that tapers from the first surface 34 a side to the second surface 34 b side of the metal sheet 34. The formed hole 62 is connected to the curved wall surface of the recess 61 and extends from the connection position 63 to the second surface 34b.

  As described above, the through hole 25 is obtained by the hole 62 and the recess 61. Specifically, the hole 62 corresponds to the second portion 29 and the recess 61 corresponds to the first portion 28.

  In addition, along with the irradiation of the laser light, the metal plate 21 extends along at least a part of the periphery of the hole 62 on the second surface 34b of the metal sheet 34 and extends from the periphery of the hole 62 on the second surface 34b. A barb 65 extending outward in the normal direction nd is formed.

  This return is also referred to as “dross” and has conventionally been considered as a factor that reduces the adhesion between the metal mask 20 and the glass substrate 42. For this reason, a technique for removing the dross formed by laser processing has been reported (for example, see JP-A-6-39988, JP-A-2006-281523, etc.). However, in the present embodiment, the extended piece 24 composed of the barb 65 is formed with the laser light irradiation, but acts to improve the adhesion between the metal mask 20 and the glass substrate 42. Thus, although the mechanism by which the extended piece 24 acts to improve the adhesion between the metal mask 20 and the glass substrate 42 has not been clarified, the following mechanism can be considered as one of the causes. However, the present invention is not limited to the following mechanism.

  In the conventional method, when forming a through-hole in a metal plate with a laser beam, a metal plate having a thickness of about 30 to 50 μm is used. For this reason, not only is the output of the laser processing apparatus set high, but the amount of metal melt that is melted by the laser beam and scattered by the assist gas inevitably increases. As a result, the thickness (height) and the height of the return (dross) formed along the periphery of the through hole are considerable. For this reason, when vapor deposition is performed using a metal plate with a barb formed, it contributes to increasing the gap, rather than filling the gap between the metal plate and the glass substrate. Furthermore, since a large amount of metal melt is scattered, the thickness and height of the dross formed by the metal melt are not stable. That is, the thickness and height of each barb (dross) formed along the peripheral edge of the corresponding through hole are formed in different sizes. For this reason, even if it vapor-deposits using the metal plate in which such a turn was formed, the quantity of the vapor deposition material 48 adhering to the glass substrate 42 will differ for every through-hole. For these reasons, the conventional method cannot perform vapor deposition with a high-definition pattern.

  On the other hand, in the present embodiment, as shown in FIG. 8 and FIG. 9, the etching is performed on the metal sheet 34 to form the concave portion 61 having a curved wall surface and tapering from the first surface 34 a side. The through holes 25 are formed by irradiating each concave portion 61 with laser light and forming a hole 62 extending from the concave portion 61 to the second surface 34b. The return 65 is formed by irradiating the hole 62 with laser light. For this reason, the output of the laser processing apparatus can be set low, and the amount of the metal melt that is melted by the laser beam and scattered by the assist gas is much smaller than that of the conventional method. As a result, the return (dross) 65 formed along the periphery of the hole 62 has a smaller thickness and a lower height than conventional. Further, since a small amount of the metal melt is scattered, the thickness and height of the return 65 formed by the metal melt is also stabilized. That is, the thickness and height of each return (dross) 65 formed along the peripheral edge of the corresponding hole 62 can be formed more uniformly than in the prior art. With such a configuration, it is considered that the adhesiveness between the metal mask 20 and the glass substrate 42 can be further improved by the turn 65, and vapor deposition with a high-definition pattern can be performed with higher accuracy.

  As described above, the size of the formed return 65 is affected by the amount of the metal melt that is melted by the laser light and scattered by the assist gas. Therefore, depending on the depth of the hole 62 formed by laser light irradiation, in other words, depending on the thickness of the portion of the metal plate 21 that is penetrated by laser light irradiation, in other words, the metal plate Depending on the thickness from the bottom surface of the recess 61 formed in 21 to the second surface 21b, that is, depending on the amount of removal by laser light irradiation, the size of the return 65 may vary. As an example, the depth of the hole 62 is 1 μm or more and 15 μm or less. When the depth of the hole 62 is 15 μm or more, the amount of the metal melt to be scattered increases and the thickness and height of the return 65 also increase. For this reason, if vapor deposition is performed using the metal mask 20 on which the turn 65 is formed, the gap between the metal mask 20 and the glass substrate 42 cannot be effectively filled, and vapor deposition is performed with a high-definition pattern. There is a risk that it will not be possible. On the other hand, when the depth of the hole 62 is 1 μm or less, the amount of the metal melt to be scattered is reduced and the thickness and height of the return 65 are also reduced. For this reason, when vapor deposition is performed using the metal mask 20 on which the turn 65 is formed, the gap between the metal mask 20 and the glass substrate 42 cannot be filled, and there is a possibility that vapor deposition with a high-definition pattern cannot be performed. is there.

  As described above, the metal mask 20 including the metal sheet 64 in which a large number of through holes 25 are formed is obtained.

  And the vapor deposition mask apparatus 10 is obtained by attaching the flame | frame 15 with respect to each metal mask 20. FIG. The frame 15 may be attached to one surface 20 a of the metal plate 21 or may be attached to the other surface 20 b of the metal plate 21.

  In addition, when forming the recessed part 61 extended elongate linearly as mentioned above, the direction where the recessed part 61 is extended, and the direction (direction where the metal sheet 34 is conveyed) where the metal sheet 34 is supplied are substantially parallel. It is preferable that In this case, it is possible to prevent the metal sheet 34 from extending or being cut at the portion of the recessed portion 61 where the thickness is thin during the manufacture of the metal mask 20.

  As described above, according to the metal mask manufacturing method of the present embodiment, the metal sheet 34 is etched from the second surface 34b side so that the concave portion 61 having a curved wall surface and tapered is formed on the first surface 34a. A step of forming from the side, and a step of irradiating each concave portion 61 with laser light to form a hole 62 extending from the concave portion 61 to the second surface 34b. By irradiating laser light into each recess 61 to form the hole 62, the hole 62 can be formed with high precision even if the hole 62 is fine. Therefore, according to such a manufacturing method, the outline of the through hole 25 including the first portion 28 and the second portion 29, which is defined by the recess 61 and the hole 62, can be formed with high accuracy.

  In particular, the accuracy of the opening in the second surface 34b of the hole 62 greatly contributes to forming the outline of the vapor deposition pattern applied to the glass substrate 42 with high accuracy. According to the present embodiment, each concave portion 61 is irradiated with laser light to form a hole 62 extending from the concave portion 61 to the second surface 34b, thereby opening the second surface 34b of the hole 62 in a desired manner. It can be accurately formed in size. Thereby, vapor deposition with a higher-definition pattern can be performed accurately.

  Further, according to the metal mask manufacturing method of the present embodiment, along with the irradiation of the laser beam, the metal mask 34 extends along at least a part of the peripheral edge of the hole 62 on the second surface 34b of the metal sheet 34, and the first A barb 65 extending outward from the peripheral edge of the hole 62 on the second surface 34b in the normal direction nd of the metal plate 21 is formed. According to such a manufacturing method, since the return 65 is formed along with the formation of the hole 62 by laser light irradiation, it is efficiently manufactured. Moreover, the thickness and height of each turn 65 can be formed uniformly.

  Various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. The duplicated explanation is omitted.

  In the embodiment described above, as shown in FIG. 4, the example is shown in which the wall surfaces of the adjacent through holes 25 are spaced apart from each other and a flat surface is formed between the adjacent through holes 25. However, it is not limited to this. FIG. 10A and FIG. 10B show examples in which the wall surfaces of the adjacent through holes 25 are connected to each other. 10A is a partial plan view, and FIG. 10B is a cross-sectional view taken along the line AA in FIG. 10A. 10A and 10B, the outline of each through hole 25 in the cross section along the normal direction nd of the metal plate 21 is opposed to the direction parallel to the plate surface of the metal plate 21. A pair of first portions 28 each extending from the first surface 21a side to a connection position 26 in the middle between the first surface 21a and the second surface 21b, and the metal plate 21 A pair of second portions 29 arranged opposite to each other in a direction parallel to the plate surface, each connected to the corresponding first portion 28 and extending from the connection position 26 to the second surface 21b. It is out. Therefore, the metal mask 20 shown in FIG. 10 also has the same effects as the present embodiment.

  In the above-described embodiment, as shown in FIG. 3, the example in which each through hole 25 is elongated from one end to the other end of the perforated region 22 is shown, but the present invention is not limited thereto. FIG. 11 shows another arrangement example of the plurality of through holes 125. In the example shown in FIG. 11, the plurality of through holes 125 are arranged side by side at equal intervals along one direction in the perforated region 22. Moreover, each through-hole 125 has a longitudinal direction in the other direction orthogonal to the said one direction, and is located in a line with the same pitch along the said other direction. For example, the metal mask 120 shown in FIG. 11 has a cross-sectional shape substantially the same as that of the through hole 25 shown in FIG. 4 in the cross-sectional view taken along the line BB in FIG. Therefore, the metal mask 120 shown in FIG. 11 also has the same effects as the present embodiment. Moreover, by producing the metal mask 120 shown in FIG. 11 by the above-described manufacturing method, the produced metal mask 120 has the extended piece 24 that exhibits the above-described excellent operational effects.

  In the above-described embodiment, the example in which the patterning is performed on the glass substrate 42 using one metal mask 20 is shown, but the present invention is not limited to this. 12 and 13 show another example and still another example applied to the glass substrate. In the example shown in FIGS. 12 and 13, a glass substrate 42 is formed using a red vapor deposition material that emits red light, a green vapor deposition material that emits green light, and a blue vapor deposition material that emits blue light. Patterning is performed.

  In the example shown in FIGS. 12 and 13, the vapor deposition pattern 140 applied to the glass substrate 42 includes a plurality of first arrays 141 and a plurality of second arrays 142, and the first array 141, the second array 142, and the like. Are arranged side by side at equal intervals alternately along one direction. Each first array 141 has a red pattern 143 made of a red vapor deposition material and a blue pattern 145 made of a blue vapor deposition material, arranged alternately at equal intervals along another direction orthogonal to one direction. It consists of. On the other hand, each 2nd arrangement | sequence 142 consists of the green pattern 144 which consists of the vapor deposition material for green arrange | positioned along the said other direction at intervals equal to the said space | interval. Each red pattern 143 and each blue pattern 145 are formed in the same shape. Each green pattern 144 has a length along one direction shorter than each red pattern 143 and each blue pattern 145. In the example shown in FIG. 12, the green pattern 144 has the same length along the other direction as the red pattern 143 and the blue pattern 145. On the other hand, in the example shown in FIG. 13, the green pattern 144 has a length along the other direction that is longer than the red pattern 143 and the blue pattern 145.

  When the vapor deposition pattern 140 shown in FIG. 12 or 13 is applied to the glass substrate 42, it is necessary to prepare a metal mask corresponding to each of the patterns 143, 144, and 145. As an example, FIG. 14 shows an arrangement example of the through holes 225 in the metal mask 220 for the red pattern 143 shown in FIG. In the example shown in FIG. 14, a through hole 225 is arranged corresponding to the red pattern 143 applied to the glass substrate 42. For example, the metal mask 220 shown in FIG. 14 has substantially the same cross-sectional shape as the through hole 25 shown in FIG. 4 in the cross-sectional view taken along the line CC in FIG. Therefore, the metal mask 220 shown in FIG. 14 also has the same function and effect as the present embodiment. Similarly, the metal mask for the red pattern 143 shown in FIG. 13, the metal mask for the green pattern 144 shown in FIGS. 12 and 13, and the metal mask for the blue pattern 145 shown in FIGS. The same effect as the form is produced. Moreover, by producing each metal mask by the above-described manufacturing method, the produced metal mask has the extended piece 24 having the above-described excellent operational effects.

  In the above-described embodiment, the example in which the hole 62 is formed after the metal sheet 34 is cut into a predetermined length by the cutting device 59 has been described, but the present invention is not limited thereto. For example, the hole 62 may be formed before the metal sheet 34 is cut into a predetermined length by the cutting device 59.

  Further, in the above-described embodiment, the example in which the metal sheet 34 is cut into a predetermined length by the cutting device 59 after the recess 61 is formed in the metal sheet 34 has been described, but the present invention is not limited thereto. For example, the step of cutting the metal sheet 34 may be performed before the recess 61 is formed in the metal sheet 34. Alternatively, the metal sheet 34 may be etched so as to have a predetermined length during the step of forming the recess 61 by etching. That is, when the recess 61 is formed by etching, the metal sheet 34 may be separated into a predetermined length by etching. In this case, the trouble of separately cutting the metal sheet 34 into a predetermined length can be saved, and the metal mask 20 can be manufactured with high production efficiency and at low cost.

  Furthermore, although the example which cut | disconnects the metal mask 20 in predetermined length was shown in embodiment mentioned above, it is not restricted to this. You may make it handle the metal sheet 34 in which many recessed parts 61 were formed as the sheet-like member 18 for metal masks, without cut | disconnecting. For example, as shown in FIG. 15, a metal mask sheet-like member 18 made of a metal sheet 34 having a large number of through holes 25 is wound around a winding core 19 without being cut, and the metal mask sheet. You may make it handle (shipment etc.) as the wound body 18a of the shaped member 18. FIG. In addition, the sheet-like member 18 for metal masks is also a protection object of this case.

  Furthermore, in the above-described embodiment, the example in which the frame 15 is attached to the metal mask 20 in which the holes 62 are formed is shown, but the present invention is not limited to this. For example, the frame 15 may be attached to the metal sheet 34 before the hole 62 is formed.

DESCRIPTION OF SYMBOLS 10 Metal mask apparatus 15 Frame 20 Metal mask 21a 1st surface 21b 2nd surface 21 Metal plate 22 Perforated area | region 23 Non-perforated area | region 24 Extension piece 24a 3rd part 25 Through-hole 26 Connection position 27 Level | step difference 28 1st part 29 1st 2 portion 34 Metal sheet 34a First surface 34b Second surface 35 Resist pattern 40 Deposition device 42 Glass substrate 48 Deposition material 44 Crucible 46 Heater 60 Through hole 61 Recess 62 Hole 63 Connection position 64 Metal sheet 65 Reversing 70 Laser processing device 72 Laser irradiation lens

Claims (7)

A metal plate having a first surface and a second surface opposite to the first surface is etched from the first surface side , and the contour of the cross section along the normal direction of the metal plate is curved. forming a recess from the side of the first surface tapering having a curved wall made,
Irradiating a laser beam in each recess to form a hole extending from the recess to the second surface, and
A method of manufacturing a metal mask by forming a through hole penetrating between the first surface and the second surface of the metal plate by the recess and the hole,
In the step of forming the hole, the hole is formed so as to connect to the curved wall surface of the recess and to taper from the first surface side toward the second surface side. Production method. In the step of forming the recess, the recess is formed to have a curved shape in a cross section along the normal direction of the metal plate,
In the step of forming the hole, two surfaces that are inclined with respect to both the plate surface of the metal plate and the normal direction of the metal plate at a connection position between the hole and the curved wall surface of the recess. The method for manufacturing a metal mask according to claim 1, wherein the steps are connected to form a circumferential step.   In the step of forming the hole, the irradiation with the laser light extends along at least a part of the peripheral edge of the through hole on the second surface, and from the peripheral edge of the through hole on the second surface. The method for manufacturing a metal mask according to claim 1, wherein an extended piece extending outward in the normal direction of the metal plate is formed. A metal plate having a first surface and a second surface opposite to the first surface;
A plurality of through holes are formed in the metal plate,
The outline of each through hole in the cross section along the normal direction of the metal plate is
The metal plates are arranged facing each other in a direction parallel to the plate surface, and each extends from the first surface side to a connection position in the middle between the first surface and the second surface. A pair of first portions that are closer to each other in a direction parallel to the plate surface of the metal plate as they go from the first surface side to the second surface side along the normal direction of the metal plate. A pair of first parts to be
A pair of second parts, which are arranged facing each other in a direction parallel to the plate surface of the metal plate, each connected to the first part on the corresponding side and extending from the connection position to the second surface. A pair of firsts approaching each other in a direction parallel to the plate surface of the metal plate as it goes from the first surface side to the second surface side along the normal direction of the metal plate. 2 parts,
In the cross section along the normal line direction of the metal plate, the first portion is a metal mask having a curved shape. 2. At the connection position in each through hole, two surfaces inclined with respect to both the plate surface of the metal plate and the normal direction of the metal plate are connected to form a circumferential step. 4. The metal mask according to 4 . In a cross section along the normal line direction of the metal plate, an angle formed by a line segment connecting both end portions of the first portion with respect to the normal line direction of the metal plate is a line segment connecting both end portions of the second portion. The metal mask according to claim 4 , wherein is larger than an angle formed with respect to a normal line direction of the metal plate.   An extension extending along at least a part of the peripheral edge of the through hole on the second surface and extending outward in the normal direction of the metal plate from the peripheral edge of the through hole on the second surface. The metal mask according to any one of claims 4 to 6, wherein a piece is provided.

Images