JP2020158810A - mask - Google Patents

Abstract

To provide a mask capable of preventing a foreign matter, etc., from being easily entangled in an end portion of a through hole when cleaning a mask.SOLUTION: A mask includes a metal plate 30 including a first surface 31, a second surface 32 positioned on the side opposite to the first surface and a through hole 40 and having a thickness of 5 μm or less. The through hole 40 has a wall surface including a first end served as an end in the first surface 31 and a second end served as an end in the second surface 32; the wall surface is positioned between the first end and the second end in the thickness direction of the metal plate 30 and includes a minimum opening diameter part having the smallest opening diameter; in the thickness direction of the metal plate 30, a distance between the minimum opening diameter part and the first end is 2.0 μm; and the second end has a curved cross sectional shape.SELECTED DRAWING: Figure 4

Description

An embodiment of the present disclosure relates to a mask provided with a metal plate including through holes.

The display device used in a portable device such as a smartphone or tablet PC preferably has high definition, and for example, the pixel density is preferably 400 ppi or more. Further, even in a portable device, there is an increasing demand for supporting ultra high definition (UHD), and in this case, the pixel density of the display device is preferably 800 ppi or more, for example.

Among display devices, organic EL display devices are attracting attention because of their good responsiveness, low power consumption, and high contrast. As a method of forming pixels of an organic EL display device, a method of forming pixels in a desired pattern by using a mask in which through holes arranged in a desired pattern are formed is known. Specifically, first, a mask is combined with a substrate for an organic EL display device. Subsequently, the vapor-deposited material containing the organic material is attached to the substrate through the through holes of the mask. By carrying out such a thin-film deposition step, it is possible to form a pixel having a thin-film deposition layer containing a thin-film deposition material on the substrate with a pattern corresponding to the pattern of the through holes of the mask.

As a method for manufacturing a mask, a method of forming a through hole in a metal plate by etching using a photolithography technique is known. For example, first, a first resist layer is formed on the first surface of the metal plate, and a second resist layer is formed on the second surface of the metal plate. Next, a region of the first surface of the metal plate that is not covered by the first resist layer is etched to form a first recess on the first surface of the metal plate. Then, a region of the second surface of the metal plate that is not covered by the second resist layer is etched to form a second recess on the second surface of the metal plate. At this time, it is possible to form a through hole penetrating the metal plate by performing etching so that the first recess and the second recess communicate with each other.

Japanese Patent No. 5382259

When the mask is manufactured by etching the region of the second surface of the metal plate that is not covered by the second resist layer, the cross-sectional shape of the end portion of the through hole located on the opposite side of the substrate is determined. It tends to be sharp and pointed. In this case, foreign matter or the like is likely to get entangled with the end of the through hole when cleaning the mask.

An embodiment of the present disclosure aims to provide a mask capable of effectively solving such a problem.

The mask according to one embodiment of the present disclosure is
A metal plate having a thickness of 10 μm or less, including a first surface and a second surface located on the opposite side of the first surface, and a through hole, is provided.
The through hole has a wall surface including a first end which is an end on the first surface and a second end which is an end on the second surface.
The wall surface includes a minimum opening diameter portion located between the first end and the second end in the thickness direction of the metal plate and having the smallest opening diameter.
In the thickness direction of the metal plate, the distance between the minimum opening diameter and the first end is 2.0 μm or less.
The second end has a curved cross-sectional shape.

In the mask according to one embodiment of the present disclosure
The metal plate may have a thickness of 2 μm or less.

In the mask according to one embodiment of the present disclosure
The distance between the minimum opening diameter portion and the first end may be 0.1 μm or more in the thickness direction of the metal plate.

In the mask according to one embodiment of the present disclosure
The ratio of the distance between the minimum opening diameter and the first end in the thickness direction of the metal plate to the thickness of the metal plate may be 0.1 or more and 0.4 or less.

In the mask according to one embodiment of the present disclosure
The second surface of the metal plate located between the two through holes may be flat.

In the mask according to one embodiment of the present disclosure
The angle formed by the direction in which the straight line passing through the minimum opening diameter portion and the second end extends and the surface direction of the first surface may be 80 ° or less.

In the mask according to one embodiment of the present disclosure
The metal plate may have an iron alloy containing nickel in an amount of 34% by mass or more and 38% by mass or less.

In the mask according to one embodiment of the present disclosure
The minimum opening size of the through hole may be 50 μm or less.

According to the mask according to the embodiment of the present disclosure, it is possible to prevent foreign matter and the like from being entangled with the end portion of the through hole when cleaning the mask.

It is a figure which shows the vapor deposition apparatus provided with the vapor deposition mask apparatus by one Embodiment of this disclosure. It is a top view which shows the vapor deposition mask apparatus by one Embodiment of this disclosure. FIG. 3 is a plan view showing a case where the effective region of the vapor deposition mask of the vapor deposition mask apparatus of FIG. 3A is viewed from the second surface side. It is a top view which shows one modification of the arrangement of the effective region of the vapor deposition mask of the vapor deposition mask apparatus of FIG. 3B. It is sectional drawing which follows the AA line of FIG. 3A. It is sectional drawing which shows the through hole and the shielding part enlarged. It is a top view which shows the through hole enlarged. It is sectional drawing which enlarges and shows the shielding part which defines a through hole. It is sectional drawing which shows the shielding part which defines a through hole further enlarged. It is a figure which shows the process of forming a resist layer on a metal plate. It is a figure which shows the process of patterning a resist layer. It is a figure which shows the 1st etching process. It is a figure which shows the filling process. It is a figure which shows the 2nd etching process. It is a figure which shows the 2nd etching process. It is a figure which shows the filler removal process. It is a figure which shows the process of patterning a resist layer in a comparative form. It is a figure which shows the process of etching a metal plate in the form of comparison. It is sectional drawing which shows the vapor-deposited substrate produced by using a mask. It is sectional drawing which enlarges and shows the vapor deposition layer formed by the vapor deposition process. It is sectional drawing which shows the vapor deposition mask produced in Example 1. FIG. It is sectional drawing which shows the vapor deposition mask produced in Example 2. FIG. It is sectional drawing which shows the vapor deposition mask produced in Example 3. FIG.

Hereinafter, the configuration of the mask and the manufacturing method thereof according to the embodiment will be described in detail with reference to the drawings. The embodiments shown below are examples of the embodiments of the present disclosure, and the present disclosure is not construed as being limited to these embodiments. Further, in the present specification, terms such as "board", "base material", "sheet", and "film" are not distinguished from each other based only on the difference in names. For example, "board" is a concept that includes members that can be called sheets or films. Further, the "plane (sheet surface, film surface)" is a plate-shaped member (sheet-shaped member) that is a target when the target plate-shaped (sheet-shaped, film-shaped) member is viewed as a whole and in a broad view. , A film-like member) that coincides with the plane direction. Further, the normal direction used for a plate-shaped (sheet-shaped, film-shaped) member refers to a normal direction with respect to a surface (sheet surface, film surface) of the member. Furthermore, as used herein, terms such as "parallel" and "orthogonal" and values of length and angle that specify the shape and geometric conditions and their degrees are bound by strict meaning. Instead, the interpretation will include the range in which similar functions can be expected.

Further, in the drawings referred to in the present embodiment, the same parts or parts having similar functions are designated by the same reference numerals or similar reference numerals, and the repeated description thereof may be omitted. In addition, the dimensional ratio of the drawing may differ from the actual ratio for convenience of explanation, or a part of the configuration may be omitted from the drawing.

It should be noted that the embodiments of the present disclosure can be combined with other embodiments and modifications as long as there is no contradiction. In addition, other embodiments and modifications thereof can be combined within a range that does not cause a contradiction. Further, the modified examples can be combined as long as there is no contradiction.

Further, in the embodiment of the present disclosure, when a plurality of steps are disclosed with respect to a method such as a manufacturing method, other steps not disclosed may be carried out between the disclosed steps. In addition, the order of the disclosed steps is arbitrary as long as there is no contradiction.

In the present embodiment, an example will be described in which the mask is a thin-film mask used for patterning an organic material on a substrate in a desired pattern when manufacturing an organic EL display device. However, the use of the mask is not particularly limited, and the present embodiment can be applied to masks used for various purposes. For example, the mask of the present embodiment may be used to manufacture a device for displaying or projecting an image or video for expressing virtual reality so-called VR or augmented reality so-called AR.

First, a thin-film deposition apparatus 80 that performs a thin-film deposition process for depositing a thin-film deposition material on an object will be described with reference to FIG. As shown in FIG. 1, the vapor deposition apparatus 80 may include a vapor deposition source (for example, a crucible 81), a heater 83, and a vapor deposition mask device 10 inside. Further, the vapor deposition apparatus 80 may further include an exhaust means for creating a vacuum atmosphere inside the vapor deposition apparatus 80. The crucible 81 accommodates a vapor deposition material 82 such as an organic light emitting material. The heater 83 heats the crucible 81 to evaporate the vapor deposition material 82 in a vacuum atmosphere. The vapor deposition mask device 10 is arranged so as to face the crucible 81.

Hereinafter, the vapor deposition mask device 10 will be described. As shown in FIG. 1, the thin-film deposition mask device 10 includes at least one thin-film deposition mask 20. The vapor deposition mask device 10 may further include a frame 15 that supports the vapor deposition mask 20. The frame 15 supports the vapor deposition mask 20 in a state of being pulled in the plane direction so that the vapor deposition mask 20 does not bend.

As shown in FIG. 1, the thin-film deposition mask device 10 is arranged in the thin-film deposition device 80 so that the thin-film deposition mask 20 faces the substrate 91, which is the object to which the thin-film deposition material 82 is attached. The thin-film deposition mask 20 has a plurality of through holes 40 through which the thin-film deposition material 82 flying from the thin-film deposition source 81 passes. In the following description, among the surfaces of the vapor deposition mask 20, the surface located on the side of the substrate 91 to which the flying vapor deposition material 82 adheres is referred to as the first surface 201, and the surface located on the opposite side of the first surface 201 is the first surface. It is referred to as two-sided 202.

As shown in FIG. 1, the vapor deposition mask device 10 may include a magnet 85 arranged on the surface of the substrate 91 opposite to the vapor deposition mask 20. By providing the magnet 85, the vapor deposition mask 20 can be attracted to the magnet 85 side by magnetic force, and the vapor deposition mask 20 can be brought into close contact with the substrate 91. As a result, it is possible to suppress the generation of shadows in the thin-film deposition process, and it is possible to improve the dimensional accuracy and position accuracy of the thin-film deposition layer formed on the substrate 91 by the vapor-filming material 82 adhering to the substrate 91. Further, the vapor deposition mask 20 may be brought into close contact with the substrate 91 by using an electrostatic chuck that utilizes electrostatic force.

FIG. 2 is a plan view showing a case where the vapor deposition mask device 10 is viewed from the first surface 201 side of the vapor deposition mask 20. As shown in FIG. 2, the thin-film deposition mask device 10 may include a plurality of thin-film deposition masks 20. In this embodiment, each vapor deposition mask 20 has a rectangular shape extending in one direction. In the thin-film deposition mask device 10, the plurality of thin-film deposition masks 20 are arranged in the width direction intersecting the length direction of the thin-film deposition mask 20. Each vapor deposition mask 20 is fixed to the frame 15 at both ends of the vapor deposition mask 20 in the length direction, for example, by welding.

The vapor deposition mask 20 shown in FIG. 2 has a pair of ear portions 21 fixed to the frame 15 by welding or the like, and an intermediate portion 22 located between the ear portions 21. The intermediate portion 22 may have at least one effective region 23 and a peripheral region 24 located around the effective region 23. In the example shown in FIG. 2, the intermediate portion 22 includes a plurality of effective regions 23 arranged at predetermined intervals along the length direction of the vapor deposition mask 20. The peripheral region 24 surrounds the plurality of effective regions 23.

When a display device such as an organic EL display device is manufactured using the vapor deposition mask 20, one effective region 23 corresponds to a display area of one organic EL display device. Therefore, according to the thin-film deposition mask device 10 shown in FIG. 2, multi-sided vapor deposition of the organic EL display device is possible. In addition, one effective area 23 may correspond to a plurality of display areas. Further, although not shown, a plurality of effective regions 23 may be arranged at predetermined intervals also in the width direction of the vapor deposition mask 20.

The effective domain 23 has, for example, a substantially quadrangular contour in a plan view, or more accurately, a substantially rectangular contour in a plan view. Although not shown, each effective region 23 can have contours having various shapes depending on the shape of the display region of the organic EL display device. For example, each effective region 23 may have a circular contour.

FIG. 3A is a plan view showing a case where the effective region 23 of the vapor deposition mask 20 is viewed from the second surface 202 side. Further, FIG. 4 is a cross-sectional view taken along the line AA of the effective region 23 of FIG. 3A. The effective region 23 includes a metal plate 30 and a plurality of through holes 40 provided in the metal plate 30. As shown in FIG. 4, the metal plate 30 includes a first surface 31 and a second surface 32 located on the opposite side of the first surface 31. The first surface 31 of the metal plate 30 constitutes the first surface 201 of the vapor deposition mask 20, and the second surface 32 of the metal plate 30 constitutes the second surface 202 of the vapor deposition mask 20. The through hole 40 penetrates from the first surface 31 to the second surface 32 of the metal plate 30. The through hole 40 has a wall surface 41 extending from the first surface 31 to the second surface 32.

As the material constituting the metal plate 30, for example, an iron alloy containing nickel can be used. The iron alloy may further contain cobalt in addition to nickel. For example, as a material of the metal plate 30, an iron alloy having a total content of nickel and cobalt of 30% by mass or more and 54% by mass or less and a cobalt content of 0% by mass or more and 6% by mass or less is used. Can be used. Specific examples of nickel or an iron alloy containing nickel and cobalt include an Invar material containing 34% by mass or more and 38% by mass or less of nickel, and a supermarket containing 30% by mass or more and 34% by mass or less of nickel and further cobalt. Examples thereof include Invar materials, low thermal expansion Fe—Ni based plating alloys containing nickel of 38% by mass or more and 54% by mass or less. By using such an iron alloy, the coefficient of thermal expansion of the metal plate 30 can be lowered. For example, when a glass substrate is used as the substrate 91, the coefficient of thermal expansion of the metal plate 30 can be set to a value as low as that of the glass substrate. As a result, during the vapor deposition process, the dimensional accuracy and position accuracy of the vapor deposition layer formed on the substrate 91 are reduced due to the difference in the coefficient of thermal expansion between the vapor deposition mask 20 provided with the metal plate 30 and the substrate 91. Can be suppressed.

The shape of the through hole 40 is defined by a metal plate 30 around the through hole 40. For example, the side surface of the shielding portion 35 constitutes the wall surface 41 of the through hole 40. The metal plate 30 around the through hole 40 functions to prevent the vapor-deposited material 82 from adhering to the display area of the substrate 91. In the following description, the metal plate 30 around the through hole 40 is also referred to as a shielding portion 35.

When the metal plate 30 is viewed along the normal direction of the surface direction D1 of the first surface 31 of the metal plate 30 constituting the vapor deposition mask 20, that is, along the thickness direction D2 of the metal plate 30, a plurality of through holes 40 At least a part of them is arranged at predetermined first pitch C1 and second pitch C2 along the first direction D11 and the second direction D12 that intersect each other. Both the first direction D11 and the second direction D12 are directions in the plane direction D1. The smaller pitch of the first pitch C1 and the second pitch C2 is determined as follows, for example, according to the pixel density of the display device or the projection device.
-When the pixel density is 600 ppi or more: Pitch is 42.3 μm or less-When the pixel density is 1200 ppi or more: Pitch is 21.2 μm or less-When the pixel density is 3000 ppi or more: Pitch is 8.5 μm or less Pixel density is 600 ppi The display device or projection device is used, for example, as an organic EL display device for a smartphone.
A display device or projection device having a pixel density of 1200 ppi is used, for example, to display or project an image or video for expressing virtual reality.
A display device or projection device having a pixel density of 3000 ppi is used, for example, to display or project an image or video for expressing augmented reality.

The arrangement of the effective region 23 is arbitrary. For example, as the arrangement of the effective region 23, a parallel arrangement may be adopted as shown in FIG. 3A, or a staggered arrangement may be adopted as shown in FIG. 3B.

In the examples shown in FIGS. 3A and 3B, the through hole 40 when the metal plate 30 is viewed along the thickness direction D2 of the metal plate 30 has a substantially rectangular contour with curved four corners. The shape of the contour can be arbitrarily determined according to the shape of the pixel. For example, it may have other polygonal shapes such as hexagons and octagons, and may have a circular shape. Moreover, the shape of the contour may be a combination of a plurality of shapes. Further, the plurality of through holes 40 may have different contour shapes from each other. When the through hole 40 has a polygonal contour, the opening size of the through hole 40 is the distance between a pair of opposing sides in the polygon, as shown in FIG. 3A.

As shown in FIG. 4, the peripheral region 24 is also composed of the same metal plate 30 as the effective region 23. The thickness H0 of the metal plate 30 in the peripheral region 24 may be larger than the thickness H1 of the metal plate 30 in the effective region 23. Similarly, the selvage portion 21 described above may also be formed of the same metal plate 30 as the effective region 23, and the thickness of the selvage portion 21 may be larger than the thickness H1 of the effective region 23. Although not shown, the thickness H0 of the peripheral region 24 and the thickness of the selvage portion 21 may be the same as the thickness H1 of the effective region 23, or may be smaller than the thickness H1 of the effective region 23.

As will be described later, the effective region 23 is formed by first performing a first etching step on the metal plate 30 from the first surface 31 side, and then performing a second etching on the metal plate 30 from the second surface 32 side. .. Therefore, the thickness H1 of the metal plate 30 in the effective region 23 is the thickness of the metal plate 30 after the second etching step.

The thickness H1 of the metal plate 30 constituting the shielding portion 35 is preferably 10 μm or less. The thickness H1 of the metal plate 30 constituting the shielding portion 35 may be 7 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, or 2 μm or less. You may. By setting the thickness H1 of the metal plate 30 constituting the shielding portion 35 to 10 μm or less, it is possible to prevent the vapor deposition material 82 from adhering to the wall surface 41 of the through hole 40 in the vapor deposition step. As a result, the ratio of the thin-film deposition material 82 that cannot pass through the through hole 40 can be reduced, and the utilization efficiency of the thin-film deposition material 82 can be improved. On the other hand, if the thickness H1 of the metal plate 30 constituting the shielding portion 35 becomes too small, the vapor deposition mask 20 is likely to be deformed or damaged when the vapor deposition mask 20 is used or transported. In consideration of this point, the thickness H1 of the metal plate 30 constituting the shielding portion 35 is preferably 0.5 μm or more. The thickness H1 of the metal plate 30 may be 1.0 μm or more, or 1.5 μm or more.

The range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 is determined by a combination of any one of the above-mentioned plurality of upper limit candidate values and any one of the above-mentioned plurality of lower limit candidate values. May be For example, the range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 may be 0.5 μm or more and 10 μm or less, 1.0 μm or more and 5 μm or less, and 1.5 μm or more and 2 μm or less. You may. Further, the range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 may be determined by any combination of any two of the above-mentioned plurality of upper limit candidate values. For example, the range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 may be 2 μm or more and 10 μm or less. Further, the range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 may be determined by any combination of any two of the above-mentioned plurality of lower limit candidate values. For example, the range of the thickness H1 of the metal plate 30 constituting the shielding portion 35 may be 0.5 μm or more and 1.5 μm or less.

The through hole 40 and the shielding portion 35 defining the through hole 40 will be described in detail with reference to FIGS. 5 and 6. FIG. 5 is an enlarged cross-sectional view showing the through hole 40 and the shielding portion 35. FIG. 6 is an enlarged plan view of the through hole 40.

As shown in FIG. 5, the wall surface 41 of the through hole 40 includes a first end 411, a second end 412, and a minimum opening diameter portion 46. The first end 411 is the end of the wall surface 41 on the first surface 31 of the metal plate 30, and the second end 412 is the end of the wall surface 41 on the second surface 32 of the metal plate 30. The minimum opening diameter portion 46 is a portion of the wall surface 41 that is located between the first end 411 and the second end 412 and has the smallest opening size.

In the example shown in FIG. 5, the wall surface 41 includes a first wall surface 43 extending from the first end 411 to the second end 412 side, a second wall surface 44 extending from the second end 412 to the first end 411 side, and a first wall surface. Includes a tip 45 at which the 43 and the second wall surface 44 meet. The tip 45 is the innermost portion of the wall surface 41 in the cross-sectional view of the through hole 40 and the shielding portion 35. The inside is the side closer to the central axis C of the through hole 40 in the cross-sectional view of the through hole 40 and the shielding portion 35. The central axis C is a straight line passing through an intermediate point between the opposing first end 411 and an opposing second end 412 in the cross-sectional view of the through hole 40. Further, the outside described later is the side away from the central axis C of the through hole 40 in the cross-sectional view of the through hole 40 and the shielding portion 35. The minimum opening diameter 46 described above includes a tip 45.

As shown in FIG. 5, the first wall surface 43 may expand inward toward the second end 412 side from the first end 411. Further, the second wall surface 44 may expand inward from the second end 412 toward the first end 411 side. In addition, the state that "the second wall surface 44 spreads inward toward the second end 412 side from the first end 411" and "the second wall surface 44 goes inward toward the first end 411 side from the second end 412". The state of "spreading in such a way" may be established when the minute unevenness having a depth or height of 200 nm or less existing on the wall surface 41 is ignored.

In FIGS. 5 and 6, reference numeral S1 represents the opening size of the through hole 40 in the minimum opening diameter portion 46 (hereinafter, also referred to as the minimum opening size), and reference numeral S2 is the opening size of the through hole 40 in the first surface 31. (Hereinafter, also referred to as a first surface opening dimension), reference numeral S3 represents an opening dimension of the through hole 40 in the second surface 32 (hereinafter, also referred to as a second surface opening dimension). Further, reference numeral S4 represents the width of the shielding portion 35 in the direction in which the plurality of through holes 40 are lined up. The first surface opening dimension S2 is the minimum opening dimension S1 or more, and the second surface opening dimension S3 is the first surface opening dimension S2 or more. The difference between the first surface opening size S2 and the minimum opening size S1 is preferably small. The value obtained by subtracting the minimum opening size S1 from the first surface opening size S2 is, for example, 0 μm or more and 2.0 μm or less. Further, the second surface opening dimension S3 is preferably larger than the first surface opening dimension S2. For example, the second surface opening size S3 is preferably at least 0.5 μm or more larger than the first surface opening size S2. The second surface opening size S3 may be larger than the first surface opening size S2 by 1 μm or more, 1.5 μm or more, or 2 μm or more. The value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 is preferably 10 μm or less. The value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be 8 μm or less, 6 μm or less, or 4 μm or less. As shown in FIG. 6, when the through hole 40 is viewed along the thickness direction of the metal plate 30, the contour of the first end 411 may surround the contour of the minimum opening diameter portion 46, and the second The contour of the end 412 may surround the contour of the first end 411.

The range of the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 is any one of the above-mentioned plurality of upper limit candidate values and any one of the above-mentioned plurality of lower limit candidate values. It may be determined by one combination. For example, the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be 0.5 μm or more and 10 μm or less, 1 μm or more and 8 μm or less, and 1.5 μm or more and 6 μm or less. It may be 2 μm or more and 4 μm or less. Further, the range of the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be determined by any combination of any two of the above-mentioned plurality of upper limit candidate values. For example, the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be 4 μm or more and 10 μm or less. Further, the range of the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be determined by any combination of any two of the above-mentioned plurality of lower limit candidate values. For example, the value obtained by subtracting the first surface opening dimension S2 from the second surface opening dimension S3 may be 0.5 μm or more and 2 μm or less.

The minimum opening size S1, the first surface opening size S2, the second surface opening size S3, and the width S4 are determined, for example, as shown in Table 1 below according to the pixel density of the display device or the projection device.

The minimum opening dimension S1, the first surface opening dimension S2, the second surface opening dimension S3, and the width S4 may be defined as ratios to the thickness H1 of the metal plate 30 in the effective region 23. For example, the ratio (= S1 / H1) of the minimum opening dimension S1 to the thickness H1 is, for example, 0.3 or more, 0.5 or more, 0.7 or more, or 1.0. It may be the above. Further, S1 / H1 is, for example, 30 or less, 25 or less, 20 or less, or 15 or less.

The range of S1 / H1 may be defined by any combination of any one of the plurality of upper limit candidate values described above and any one of the plurality of lower limit candidate values described above. For example, S1 / H1 may be 0.3 or more and 30 or less, 0.5 or more and 25 or less, 0.7 or more and 20 or less, and 1.0 or more and 15 or less. There may be. Further, the range of S1 / H1 may be defined by any combination of two of the above-mentioned plurality of upper limit candidate values. For example, S1 / H1 may be 15 or more and 30 or less. Further, the range of S1 / H1 may be defined by any combination of two of the above-mentioned plurality of lower limit candidate values. For example, S1 / H1 may be 0.3 or more and 1.0 or less.

In FIG. 5, reference numeral L1 represents a virtual straight line passing through the minimum opening diameter portion 46 and the second end 412 in the cross-sectional view of the through hole 40. Reference numeral θ1 represents an angle formed by the direction in which the straight line L1 extends and the surface direction of the first surface 31 of the metal plate 30. The angle θ1 is preferably 80 ° or less. The angle θ1 may be 70 ° or less, 60 ° or less, 50 ° or less, 45 ° or less, or 40 ° or less. The angle θ1 is preferably 10 ° or more. The angle θ1 may be 15 ° or more, 20 ° or more, 25 ° or more, or 30 ° or more.

The range of the angle θ1 may be defined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the angle θ1 may be 10 ° or more and 80 ° or less, 15 ° or more and 70 ° or less, 20 ° or more and 60 ° or less, and 25 ° or more and 50 ° or less. It may be 30 ° or more and 45 ° or less. Further, the range of the angle θ1 may be defined by any combination of two of the plurality of upper limit candidate values. For example, the angle θ1 may be 40 ° or more and 80 ° or less. Further, the range of the angle θ1 may be defined by any combination of two of the plurality of lower limit candidate values. For example, the angle θ1 may be 10 ° or more and 30 ° or less.

Hereinafter, the technical meaning of the angle θ1 will be described. In the thin-film deposition step using the thin-film deposition mask 20, the thin-film deposition material 82 is inclined with respect to the thickness direction of the metal plate 30 in addition to the components flying along the thickness direction of the metal plate 30 from the vapor deposition source 81 toward the substrate 91. It may contain components that fly along the direction. A part of the thin-film deposition material 82 flying along the inclined direction reaches the second surface 32 of the metal plate 30 and the wall surface 41 of the through hole 40 and adheres to the substrate 91 before reaching the substrate 91. Therefore, the thickness of the thin-film deposition layer formed on the substrate 91 tends to become thinner as it approaches the wall surface 41 of the through hole 40. Such a phenomenon in which the adhesion of the thin-film deposition material 82 to the substrate 91 is hindered by the wall surface 41 of the through hole 40 is also referred to as a shadow. According to the present embodiment, the occurrence of shadow can be suppressed by configuring the wall surface 41 of the through hole 40 so that the above-mentioned angle θ1 is 80 ° or less.

By the way, reducing the angle θ1 leads to an increase in the distance S5 (see FIG. 5) between the minimum opening diameter portion 46 and the second end 412 in the surface direction of the first surface 31 of the metal plate 30. The expansion of the distance S5 leads to the expansion of the width S4 of the shielding portion 35. The pitch of the through holes 40 described above is equal to the sum of the minimum opening dimension S1 and the width S4 of the shielding portion 35. Therefore, as the distance S5 increases, it is limited to reduce the pitch of the through holes 40.

Here, in the present embodiment, as described above, the thickness H1 of the metal plate 30 in the effective region 23 is small, for example, 10 μm or less. Therefore, the distance S5 required to reduce the angle θ1 is shorter than that of the conventional thin-film deposition mask having a thickness of more than 10 μm, for example. Therefore, according to the present embodiment, the angle θ1 can be set to 80 ° or less while keeping the pitch of the through holes 40 small.

Next, the shapes of the through hole 40 and the shielding portion 35 will be described in more detail with reference to FIG. 7. FIG. 7 is an enlarged cross-sectional view showing the shielding portion 35 defining the through hole 40.

In FIG. 7, reference numeral H2 represents a distance between the minimum opening diameter portion 46 and the first end 411 in the thickness direction D2 of the metal plate 30. In the following description, the distance H2 is also referred to as the height of the first wall surface 43. The height H2 of the first wall surface 43 is preferably 2.0 μm or less. The height H2 of the first wall surface 43 may be 1.5 μm or less, 1.0 μm or less, 0.8 μm or less, or 0.6 μm or less. By setting the height H2 of the first wall surface 43 to 1.0 μm or less, it is possible to suppress the position of the end portion of the vapor deposition layer 92 formed on the substrate 91 by the vapor deposition step in the plane direction of the substrate 91. it can. This makes it possible to reduce the margin provided with respect to the distance between two adjacent pixels.

On the other hand, in the manufacturing process of the vapor deposition mask 20, if the design value of the height H2 of the first wall surface 43 is made too small, the etching performed from the second surface 32 side may reach the first surface 31 side. Conceivable. When the etching performed from the second surface 32 side reaches the first surface 31 side, the variation between the minimum opening dimension S1 and the first surface opening dimension S2 becomes large. In consideration of this point, the height H2 of the first wall surface 43 is preferably 0.1 μm or more. The height H2 of the first wall surface 43 may be 0.2 μm or more, or 0.3 μm or more.

The range of the height H2 of the first wall surface 43 may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the height H2 of the first wall surface 43 may be 0.1 μm or more and 2.0 μm or less, 0.2 μm or more and 1.5 μm or less, and 0.3 μm or more and 1.0 μm or less. You may. Further, the range of the height H2 of the first wall surface 43 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the height H2 of the first wall surface 43 may be 0.6 μm or more and 2.0 μm or less. Further, the range of the height H2 of the first wall surface 43 may be determined by any combination of two of the plurality of lower limit candidate values. For example, the height H2 of the first wall surface 43 may be 0.1 μm or more and 0.3 μm or less.

The preferred range of the height H2 of the first wall surface 43 may be defined as a relative value with respect to the thickness H1 of the metal plate 30 constituting the shielding portion 35. For example, the ratio (H2 / H1) of the height H2 to the thickness H1 of the metal plate 30 constituting the shielding portion 35 is preferably 0.4 or less. H2 / H1 may be 0.35 or less, or may be 0.3 or less. Further, H2 / H1 is preferably 0.1 or more. H2 / H1 may be 0.15 or more, or 0.2 or more.

Further, the range of H2 / H1 may be defined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, H2 / H1 may be 0.1 or more and 0.4 or less, 0.15 or more and 0.35 or less, or 0.2 or more and 0.3 or less. Further, the range of H2 / H1 may be determined by any combination of two of the plurality of upper limit candidate values. For example, H2 / H1 may be 0.3 or more and 0.4 or less. Further, the range of H2 / H1 may be defined by any combination of two of the plurality of lower limit candidate values. For example, H2 / H1 may be 0.1 or more and 0.2 or less.

In FIG. 7, reference numeral H3 represents a distance between the minimum opening diameter portion 46 and the second end 412 in the thickness direction D2 of the metal plate 30. In the following description, the distance H3 is also referred to as the height of the second wall surface 44. The height H3 of the second wall surface 44 is preferably 4 μm or less. The height H3 of the second wall surface 44 may be 3.5 μm or less, or 3 μm or less. The height H3 of the second wall surface 44 is preferably 1 μm or more. The height H3 of the second wall surface 44 may be 1.5 μm or more, or 2 μm or more.

The range of the height H3 of the second wall surface 44 may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the height H3 of the second wall surface 44 may be 1 μm or more and 4 μm or less, 1.5 μm or more and 3.5 μm or less, or 2 μm or more and 3 μm or less. Further, the range of the height H3 of the second wall surface 44 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the height H3 of the second wall surface 44 may be 3 μm or more and 4 μm or less. Further, the range of the height H3 of the second wall surface 44 may be determined by any combination of two of the plurality of lower limit candidate values. For example, the height H3 of the second wall surface 44 may be 1 μm or more and 2 μm or less.

As will be described later, the second surface 32 of the shielding portion 35 located between the two through holes 40 covers the entire portion of the metal plate 30 corresponding to the effective region 23 from the second surface 32 side of the metal plate 30. Formed by etching. Therefore, the second surface 32 of the shielding portion 35 located between the two through holes 40 is flat. “The second surface is flat” is as shown in FIG. 7 within the range of the distance S6 centered on the center point in the surface direction D1 of the first surface 31 of the metal plate 30 in the cross-sectional view of the shielding portion 35. It means that the maximum value H4 of the distance between the valley and the mountain appearing on the second surface 32 is 1 μm or less. The distance S6 is 1/2 of the width S4 of the shielding portion 35. H4 may be 0.8 μm or less, or 0.6 μm or less.

Since the first surface 31 of the shielding portion 35 is not etched in the manufacturing process of the vapor deposition mask 20, the maximum value H4 of the distance between the valley portion and the mountain portion appearing on the second surface 32 is the valley appearing on the first surface 31. It is larger than the maximum value of the distance between the part and the mountain part. H4 is, for example, 0.05 μm or more, 0.07 μm or more, or 0.1 μm or more.

The range of the maximum value H4 of the distance between the valley and the mountain appearing on the second surface 32 is any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. It may be determined by a combination. For example, H4 may be 0.05 μm or more and 1 μm or less, 0.07 μm or more and 0.8 μm or less, or 0.1 μm or more and 0.6 μm or less. Further, H4 may be determined by any combination of two of the plurality of upper limit candidate values. For example, H4 may be 0.6 μm or more and 1 μm or less. Further, H4 may be determined by any combination of two of the plurality of lower limit candidate values. For example, H4 may be 0.05 μm or more and 0.1 μm or less.

Further, as will be described later, the second wall surface 44 of the wall surface 41 of the through hole 40 is made of metal by the etching solution that has penetrated between the filler 52 filled on the first surface 31 side of the metal plate 30 and the metal plate 30. It is a surface formed by side etching the plate 30. In this case, as shown in FIG. 7, the cross-sectional shape of the second end 412 of the wall surface 41 is curved. Since the cross-sectional shape of the second end 412 is curved, the thin-film deposition material 82 flying along the direction inclined with respect to the thickness direction of the metal plate 30 adheres to the periphery of the second end 412 and the second end 412. It becomes difficult. Further, in the step of cleaning the vapor deposition mask 20, foreign matter is less likely to be entangled with the second end 412 as compared with the case where the second end 412 is sharply pointed. The foreign substance is, for example, cellulose.

A protective film or the like may be attached to the second surface 32 of the metal plate 30 of the vapor deposition mask 20 when the vapor deposition mask 20 is conveyed, and then the protective film may be peeled off. In this case, since the cross-sectional shape of the second end 412 is curved, the protective film can be easily peeled off as compared with the case where the second end 412 is sharply pointed. For example, it is possible to prevent the protective film from being caught on the second end 412 or the adhesive of the protective film from adhering to the second end 412 and remaining as a foreign substance.

The radius of curvature R1 of the cross-sectional shape of the second end 412 is preferably 0.3 μm or more. The radius of curvature R1 may be 0.5 μm or more, or 1.0 μm or more. As a result, the second end 412 can exert the above-mentioned effect more remarkably. The radius of curvature R1 of the cross-sectional shape of the second end 412 is preferably 2.0 μm or less. The radius of curvature R1 may be 1.5 μm or less, or 1.0 μm or less.

Further, the range of the radius of curvature R1 is determined by any combination of any one of the plurality of upper limit candidate values and the plurality of lower limit candidate values, as in the case of the thickness H1 described above. You may. For example, the radius of curvature R1 of the cross-sectional shape of the second end 412 may be 0.3 μm or more and 2.0 μm or less, or 0.5 μm or more and 1.5 μm or less. Further, the range of the radius of curvature R1 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the radius of curvature R1 of the cross-sectional shape of the second end 412 may be 1.0 μm or more and 2.0 μm or less. Further, the range of the radius of curvature R1 may be determined by any combination of two of the plurality of lower limit candidate values. For example, the radius of curvature R1 of the cross-sectional shape of the second end 412 may be 0.3 μm or more and 1.0 μm or less.

Next, a method of specifying the second end 412 will be described with reference to FIG. FIG. 8 is a further enlarged view of the shielding portion 35 defining the through hole 40. The second end 412 may be defined as a portion including an angle change point at which the amount of change in the direction in which the second wall surface 44 spreads is 30 ° or more. Hereinafter, the angle change point will be described.

In FIG. 8, reference numeral P1 represents one point located on the second wall surface 44 in the cross-sectional view of the effective region 23. Further, the reference numeral P2 represents a point displaced from the point P1 by 500 nm along the second wall surface 44 toward the side approaching the second surface 32. Reference numeral Q1 represents a straight line tangent to the second wall surface 44 at the point P1, and reference numeral Q2 represents a straight line tangent to the second wall surface 44 at the point P2. The symbol δ represents the angle formed by the direction in which the straight line Q1 extends and the direction in which the straight line Q2 extends. The angle δ calculated in this way is the amount of change in the angle of the second wall surface 44 at the point P1. The second end 412 includes an angle change point at which the amount of change in angle calculated in this way is 30 ° or more.

In the example shown in FIG. 8, the amount of change in the angle is 30 ° or more not only at the point P1 but also at the point located between the points Px and Py in FIG. In this case, the second end 412 is defined as a center point in the range of the second wall surface 44 in which the amount of change in angle is 30 ° or more.

Method for Manufacturing the Vapor Deposition Mask Next, a method for manufacturing the vapor deposition mask 20 by processing the metal plate 30 will be described mainly with reference to FIGS. 9 to 15.

First, the metal plate 30 is prepared. As the metal plate 30, a continuously extending metal plate 30 in a state of being unwound from the roll may be used. In this case, the manufacturing process of the vapor deposition mask 20 may be carried out on the metal plate 30 conveyed along the guide roller. Further, as the metal plate 30, one metal plate 30 having dimensions corresponding to an apparatus such as an exposure machine used according to the manufacturing process of the vapor deposition mask 20 may be used.

The thickness H0 of the metal plate 30 is preferably 15 μm or more. The thickness H0 of the metal plate 30 may be 20 μm or more, or 30 μm or more. By setting the thickness H0 of the metal plate 30 to 10 μm or more, it is possible to prevent the metal plate 30 from being damaged due to the load applied to the metal plate 30 in the manufacturing process of the vapor deposition mask 20. The thickness H0 of the metal plate 30 is preferably 200 μm or less. The thickness H0 may be 100 μm or less, or 50 μm or less.

Further, the range of the thickness H0 of the metal plate 30 may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the thickness H0 of the metal plate 30 may be 10 μm or more and 200 μm or less, 15 μm or more and 100 μm or less, or 20 μm or more and 50 μm or less. Further, the range of the thickness H0 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the thickness H0 of the metal plate 30 may be 50 μm or more and 200 μm or less. Further, the range of the thickness H0 may be determined by any combination of two of the plurality of lower limit candidate values. For example, the thickness H0 of the metal plate 30 may be 10 μm or more and 20 μm or less.

Subsequently, as shown in FIG. 9, the first resist layer 51 is formed on the first surface 31 of the metal plate 30. The first resist layer 51 may be a layer formed by applying a solution containing a resist material to the first surface 31 and solidifying it. Alternatively, the first resist layer 51 may be a layer formed by attaching a film such as a dry film to the first surface 31. In order to reduce the thickness of the first resist layer 51, it is preferable to adopt a so-called coating type resist layer in which a solution containing a resist material is applied and solidified.

When the coating type is adopted, for example, the first resist layer 51 can be formed by applying a solution containing a photodissolving type, so-called positive type photosensitive material, to the first surface 31 and solidifying it. At this time, the resist layer firing step of firing the first resist layer 51 may be performed. The photosensitive material may be a photocurable type, a so-called negative type.

Examples of positive photosensitive materials include novolac-based positive resists such as SC500. Examples of the negative type photosensitive material include casein resist and the like.

The resist layer firing temperature at which the first resist layer 51 is fired is set according to the photosensitive material. For example, when a novolak-based positive resist is used as the photosensitive material, the resist layer firing temperature is preferably 40 ° C. or higher, may be 50 ° C. or higher, or may be 60 ° C. or higher. When a novolak-based positive resist is used as the photosensitive material, the resist layer firing temperature is preferably 180 ° C. or lower, and may be 170 ° C. or higher, or 160 ° C. or lower.

When a novolak-based positive resist is used as the photosensitive material, the resist layer firing temperature may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. Good. For example, the resist layer firing temperature may be 40 ° C. or higher and 180 ° C. or lower, 50 ° C. or higher and 170 ° C. or lower, or 60 ° C. or higher and 160 ° C. or lower. Further, the range of the resist layer firing temperature may be determined by any combination of two of the plurality of upper limit candidate values. For example, the resist layer firing temperature may be 160 ° C. or higher and 180 ° C. or lower. Further, the range of the resist layer firing temperature may be determined by any combination of two of the plurality of lower limit candidate values. For example, the resist layer firing temperature may be 40 ° C. or higher and 60 ° C. or lower.

When casein resist is used as the photosensitive material, the resist layer firing temperature is preferably 80 ° C. or higher, may be 100 ° C. or higher, or may be 120 ° C. or higher. When a novolak-based positive resist is used as the photosensitive material, the resist layer firing temperature is preferably 250 ° C. or lower, may be 230 ° C. or higher, or may be 200 ° C. or lower.

When casein resist is used as the photosensitive material, the resist layer firing temperature may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the resist layer firing temperature may be 80 ° C. or higher and 250 ° C. or lower, 100 ° C. or higher and 230 ° C. or lower, or 120 ° C. or higher and 200 ° C. or lower. Further, the range of the resist layer firing temperature may be determined by any combination of two of the plurality of upper limit candidate values. For example, the resist layer firing temperature may be 200 ° C. or higher and 250 ° C. or lower. Further, the range of the resist layer firing temperature may be determined by any combination of two of the plurality of lower limit candidate values. For example, the resist layer firing temperature may be 80 ° C. or higher and 120 ° C. or lower.

The thickness of the first resist layer 51 is preferably 5.0 μm or less. The thickness of the first resist layer 51 may be 3.0 μm or less, or 2.0 μm or less. By reducing the thickness of the first resist layer 51 to 5.0 μm or less, it is possible to suppress the variation of the first surface opening size S2 among the plurality of through holes 40. The thickness of the first resist layer 51 is preferably 1.0 μm or more. The thickness of the first resist layer 51 may be 1.5 μm or more, or 2.0 μm or more.

The thickness range of the first resist layer 51 is determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values, as in the case of the thickness H1 described above. It may be determined. For example, the thickness of the first resist layer 51 may be 1.0 μm or more and 5.0 μm or less, or 1.5 μm or more and 3.0 μm or less. Further, the range of the thickness of the first resist layer 51 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the thickness of the first resist layer 51 may be 2.0 μm or more and 5.0 μm or less. Further, the range of the thickness of the first resist layer 51 may be determined by any combination of two of the plurality of lower limit candidate values. For example, the thickness of the first resist layer 51 may be 1.0 μm or more and 2.0 μm or less.

As shown in FIG. 9, the second resist layer 56 may be formed on the second surface 32 of the metal plate 30. The photosensitive material contained in the second resist layer 56 may be the same as or different from the photosensitive material contained in the first resist layer 51. Although not shown, the second resist layer 56 may not be provided on the second surface 32 of the metal plate 30.

Subsequently, an exposure step for exposing the first resist layer 51 is carried out, and then a development step for developing the first resist layer 51 is carried out. As a result, as shown in FIG. 10, the first resist layer 51 is partially removed, and the portion of the first surface 31 of the metal plate 30 corresponding to the effective region 23 is covered with the first resist layer 51. A plurality of unexposed areas 53 can be provided.

When the second resist layer 56 is formed on the second surface 32 of the metal plate 30, the second resist layer 56 may be exposed and developed as shown in FIG. In the present embodiment, the second resist layer 56 of the portion corresponding to the effective region 23 of the second surface 32 is removed, and the second resist layer 56 remains in the portion corresponding to the peripheral region 24 and the ear portion 21. The second resist layer 56 is exposed and developed. Although not shown, the second resist layer 56 is removed from the portion of the second surface 32 corresponding to the effective region 23 and the peripheral region 24, and the second resist layer 56 remains in the portion corresponding to the ear portion 21. The second resist layer 56 may be exposed and developed.

Although not shown, the second resist layer 56 may remain slightly on the portion of the second surface 32 corresponding to the effective region 23 to the extent that the etching uniformity of the second surface 32 is not impaired. For example, a continuous exposed region of the second surface 32 corresponding to the effective region 23 and not provided with the second resist layer 56 is 0.5 μm in at least one surface direction of the second surface 32. It may have the above dimensions.

Subsequently, the first etching step of etching the metal plate 30 from the side of the third first surface 31 with the first resist layer 51 as a mask is performed. As a result, as shown in FIG. 11, the first recess 50 can be formed on the first surface 31. The first recess 50 has, for example, a hemispherical shape.

Subsequently, as shown in FIG. 12, a filling step of filling the first recess 50 with the filler 52 is performed. For example, a solution containing the filler 52 is applied to the first surface 31 side of the metal plate 30. As the filler 52, a thermoplastic resin, a photoresist or the like can be used. The photoresist is, for example, a positive resist containing a positive photosensitive material. As shown in FIG. 12, the filler 52 may cover the first resist layer 51. Specific examples of the resin constituting the filler 52 include an acrylic resin and a novolac resin.

Subsequently, a filler firing step of firing the filler 52 is performed. When a thermoplastic resin is used as the filler 52, the filler firing step may not be performed.

In FIG. 12, reference numeral H5 represents the distance from the first surface 31 to the top of the filler 52 in the thickness direction of the metal plate 30. The top is the portion of the filler 52 that is farthest from the first surface 31 in the thickness direction of the metal plate 30. The distance H5 is equal to the depth of the first recess 50. The distance H5 is preferably 7.0 μm or less. The distance H5 may be 6.0 μm or less, or 5.0 μm or less. The distance H5 is preferably 1.0 μm or more. The distance H5 may be 2.0 μm or more, 3.0 μm or more, or 4.0 μm or more.

The range of the distance H5 may be defined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the distance H5 may be 1.0 μm or more and 7.0 μm or less, 2.0 μm or more and 6.0 μm or less, or 3.0 μm or more and 5.0 μm or less. Further, the range of the distance H5 may be determined by any combination of two of the plurality of upper limit candidate values. For example, the distance H5 may be 6.0 μm or more and 7.0 μm or less. Further, the range of the distance H5 may be defined by any combination of two of the plurality of lower limit candidate values. For example, the distance H5 may be 1.0 μm or more and 4.0 μm or less.

The ratio of the distance H5 to the thickness H0 of the metal plate 30 before etching (= H5 / H0) is preferably 0.1 or more. H5 / H0 may be 0.3 or more, or 0.5 or more. By setting H5 / H0 to 0.1 or more, it is possible to suppress the time required for the etching on the second surface 32 side, which will be described later, to reach the filler 52 from varying depending on the position. Further, H5 / H0 is preferably 0.9 or less, 0.7 or less, or 0.5 or less.

The range of H5 / H0 may be defined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, H5 / H0 may be 0.1 or more and 0.9 or less, or 0.3 or more and 0.7 or less. Further, the range of H5 / H0 may be defined by any combination of two of the plurality of upper limit candidate values. For example, H5 / H0 may be 0.5 or more and 0.9 or less. Further, the range of H5 / H0 may be defined by any combination of two of the plurality of lower limit candidate values. For example, H5 / H0 may be 0.1 or more and 0.5 or less.

Subsequently, a second etching step of etching the metal plate 30 from the second surface 32 side is performed. As the etching solution, a ferric chloride solution and a solution containing hydrochloric acid can be used. The temperature of the etching solution is, for example, 25 ° C. or higher, 30 ° C. or higher, or 35 ° C. or higher. The temperature of the etching solution is, for example, 80 ° C. or lower, 70 ° C. or lower, or 60 ° C. or lower.

The temperature range of the etching solution may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values. For example, the temperature of the etching solution may be 25 ° C. or higher and 80 ° C. or lower, 30 ° C. or higher and 70 ° C. or lower, or 35 ° C. or higher and 60 ° C. or lower. Further, the temperature range of the etching solution may be determined by any combination of two of the plurality of upper limit candidate values. For example, the temperature of the etching solution may be 60 ° C. or higher and 80 ° C. or lower. Further, the temperature range of the etching solution may be determined by any combination of two of the plurality of lower limit candidate values. For example, the temperature of the etching solution may be 25 ° C. or higher and 35 ° C. or lower.

As shown in FIG. 13, the second etching step continues until the second surface 32 of the metal plate 30 located in the effective region 23 is located at least on the first surface 31 side of the top 521 of the filler 52. Will be done. By allowing the etching from the second surface 32 side to reach the top 521 of the filler 52, the through hole 40 can be formed in the vapor deposition mask 20.

Further, the second etching step is continued until the second surface opening dimension S3 of the through hole 40 becomes equal to or larger than the minimum opening dimension S1 at the tip 45. In the second etching step, preferably, the second surface opening dimension S3 of the through hole 40 is larger than the minimum opening dimension S1 by 1 μm or more, and more preferably, the second surface opening dimension S3 of the through hole 40 is the minimum opening dimension. It is continued until it is 2 μm or more larger than S1. Further, the second etching step may be continued until the second surface opening dimension S3 of the through hole 40 becomes larger than the first surface opening dimension S2. In the second etching step, preferably, the second surface opening dimension S3 of the through hole 40 is larger than the first surface opening dimension S2 by 1 μm or more, and more preferably, the second surface opening dimension S3 of the through hole 40 is the first. It is continued until it is 2 μm or more larger than the one-sided opening size S2.

Further, preferably, in the second etching step, as shown in FIG. 14, the ratio of the thickness H1 of the metal plate 30 located in the effective region 23 to the distance H5 from the first surface 31 to the top 521 of the filler 52 ( = H1 / H5) is continued until 0.9 or less. As a result, the etching solution easily penetrates between the filler 52 and the metal plate 30. As a result, as shown in FIG. 14, the metal plate 30 around the filler 52 is side-etched, and a gap 57 is likely to be formed between the filler 52 and the metal plate 30. The surface formed on the metal plate 30 by side etching constitutes the above-mentioned second wall surface 44 of the wall surface 41 of the through hole 40. By controlling the amount of side etching, the second wall surface 44 can have a shape that expands inward toward the first end 411 side from the second end 412. H1 / H5 may be 0.8 or less, 0.7 or less, or 0.6 or less. Further, H1 / H5 may be 0.1 or more, 0.2 or more, or 0.3 or more.

The range of H1 / H5 may be determined by any combination of any one of the plurality of upper limit candidate values and any one of the plurality of lower limit candidate values, as in the case of the thickness H1 described above. Good. For example, H1 / H5 may be 0.1 or more and 0.9 or less, 0.2 or more and 0.8 or less, or 0.3 or more and 0.7 or less. Further, the range of H1 / H5 may be defined by any combination of two of the plurality of upper limit candidate values. For example, H1 / H5 may be 0.6 or more and 0.9 or less. Further, the range of H1 / H5 may be defined by any combination of two of the plurality of lower limit candidate values. For example, H1 / H5 may be 0.1 or more and 0.3 or less.

The time for continuing etching in the second etching step can be determined, for example, based on the etching condition data acquired in advance. The etching condition data includes, for example, the relationship between the time for continuing etching and the thickness H1 of the effective region 23. The etching condition data may include the relationship between the time for continuing the etching and the height H2 of the first wall surface 43, and includes the relationship between the time for continuing the etching and the height H3 of the second wall surface 44. You may be. Based on these etching condition data, it is possible to determine the time for continuing etching in the second etching step so that the thickness H1, height H2, height H3, and the like become appropriate values.

Subsequently, as shown in FIG. 15, a filler removing step of removing the filler 52 is carried out. As a result, a through hole 40 is created in the metal plate 30. As the solution for removing the filler 52, a solution containing sodium hydroxide or the like can be used. In addition, a resist layer removing step of removing the first resist layer 51 and the second resist layer 56 is carried out. As the solution for removing the resist layer, a solution containing sodium hydroxide or the like can be used. In this way, it is possible to obtain a vapor deposition mask 20 having a metal plate 30 provided with a plurality of through holes 40. The filler removing step and the resist layer removing step may be carried out at the same time by using a solution or the like capable of removing both the filler and the resist layer.

In the present embodiment, as described above, the etching of the second surface 32 in the portion of the metal plate 30 corresponding to the effective region 23 is performed without providing the resist layer on the second surface 32. In other words, a recess extending so as to straddle the plurality of first recesses 50 formed on the first surface 31 side is formed on the second surface 32 side. As a result, it is possible to prevent the position of the minimum opening diameter portion 46 of the through hole 40 and the minimum opening dimension S1 from fluctuating among the plurality of through holes 40.

Next, the effect of the present embodiment will be further described by comparing the present embodiment with the comparative form. 16 and 17 are diagrams showing a method of manufacturing the vapor deposition mask 20 in the comparative form. In the comparative modes shown in FIGS. 16 and 17, the same parts as those in the above-described embodiment or parts having the same functions are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 16 is a cross-sectional view showing a first resist layer 51 provided on the first surface 31 of the metal plate 30 and a second resist layer 56 provided on the second surface 32 in a comparative form. As shown in FIG. 16, in the comparative mode, a plurality of exposed regions 58 not covered by the second resist layer 56 are provided on the portion of the second surface 32 of the metal plate 30 corresponding to the effective region 23. Then, as in the case of the present embodiment, the metal plate 30 is etched from the first surface 31 side to form the first recess 50, and then the first recess 50 is filled with the filler 52. After that, the metal plate 30 is etched from the second surface 32 side using the second resist layer 56 as a mask to form a plurality of second recesses 55 on the second surface 32. As shown in FIG. 17, a plurality of through holes 40 can be formed in the metal plate 30 by allowing the plurality of first recesses 50 and the plurality of second recesses 55 to communicate with each other.

By the way, in the comparative form, due to an error in the alignment of the exposure mask and the like, as shown in the right side portion of FIG. 16, the relative position of the second resist layer 56 with respect to the first resist layer 51 is determined from the design. It may shift. In this case, as shown in the right side portion of FIG. 17, the relative positions of the second recess 55 with respect to the first recess 50 are displaced, and as a result, the first recess 50 and the second recess 50 in one through hole 40. The position where the 55 meets may vary in the thickness direction of the metal plate 30. That is, as indicated by reference numeral H6 in FIG. 17, the position of the minimum opening diameter portion 46 of the through hole 40 may vary in the thickness direction of the metal plate 30. As a result, the height H2 of the first wall surface 43 varies.

Further, in the comparative form, the etching from the second surface 32 side of the metal plate 30 proceeds individually in the plurality of second recesses 55. In this case, the etching rate in each of the second recesses 55 may also vary due to variations in the position of the top of the filler 52, variations in the concentration of the etching solution, variations in the flow of the etching solution, and the like. As a result, the position where the first recess 50 and the second recess 55 meet varies, and the minimum value of the opening size of the through hole 40 tends to vary. In addition, the height H2 of the first wall surface 43 also varies.

On the other hand, in the present embodiment, the second resist layer 56 is not provided on most of the portion of the second surface 32 corresponding to at least the effective region 23. Therefore, in the second etching step, the speed and concentration of the etching solution in the portion corresponding to the effective region 23 are likely to be uniform as compared with the comparative form. Therefore, it is possible to prevent the dimensions and positions of the minimum opening diameter portion 46 and the height H2 of the first wall surface 43 from fluctuating among the plurality of through holes 40 of the effective region 23.

Further, in the present embodiment, since the second resist layer 56 is not provided in most of the portion of the second surface 32 corresponding to at least the effective region 23, it is caused by an error in the position of the second resist layer 56. Errors in the dimensions and position of the minimum opening diameter 46 are unlikely to occur. Also in this respect, it is possible to prevent the dimensions and positions of the minimum opening diameter portion 46 and the height H2 of the first wall surface 43 from fluctuating among the plurality of through holes 40 of the effective region 23.

Further, in the present embodiment, since it is possible to suppress variations in the etching rate and the like in the second etching step, the height H2 of the first wall surface 43 is reduced while leaving the first wall surface 43. It becomes easy to carry out the etching process. Therefore, the design value and the measured value of the height H2 of the first wall surface 43 can be reduced, for example, 2.0 μm or less. As a result, it is possible to prevent shadows from being generated during the vapor deposition process.

Manufacturing Method of Vapor Deposition Mask Device Next, a welding step of welding the vapor deposition mask 20 obtained as described above to the frame 15 is carried out. This makes it possible to obtain a vapor deposition mask device 10 including the vapor deposition mask 20 and the frame 15.

Vapor deposition Method Next, a method of adhering the vapor deposition material 82 to the substrate 91 using the vapor deposition mask 20 according to the present embodiment and forming the vapor deposition layer 92 on the substrate 91 as shown in FIG. 18 will be described. In the following description, an article including at least a substrate 91 and a vapor deposition layer 92 formed on the substrate 91 by a vapor deposition step is also referred to as a vapor deposition substrate 90. The vapor deposition substrate 90 is used in an organic EL display device or the like.

In the vapor deposition step of adhering the vapor deposition material 82 to the substrate 91 using the vapor deposition mask 20, first, the vapor deposition mask device 10 is arranged so that the vapor deposition mask 20 faces the substrate 91. Further, the vapor deposition mask 20 is brought into close contact with the substrate 91 using the magnet 85. Further, the inside of the vapor deposition apparatus 80 is made into a vacuum atmosphere. In this state, by evaporating the thin-film deposition material 82 and flying it to the substrate 91, the thin-film deposition material 82 can be attached to the substrate 91 in a pattern corresponding to the through holes 40 of the vapor deposition mask 20.

FIG. 22 is an enlarged cross-sectional view showing the vapor deposition layer 92 formed on the substrate 91 by the vapor deposition process. According to the method for manufacturing the vapor deposition mask 20 described above, it is possible to suppress variations in the etching rate and the like in the second etching step, so that the height H2 of the first wall surface 43 of the through hole 40 can be set small. .. Therefore, the width K1 of the first wall surface 43 in the surface direction of the first surface 31 of the metal plate 30 can be reduced. As a result, as shown in FIG. 22, the width K1 of the portion of the vapor deposition layer 92 formed outside the minimum opening diameter 46 of the through hole 40 of the vapor deposition mask 20 varies among the plurality of pixels. It can be suppressed. Therefore, it is possible to reduce the margin provided in the design of the thin-film deposition substrate 90 in consideration of the interference of adjacent pixels.

Further, according to the above-mentioned manufacturing method of the vapor deposition mask 20, it is possible to suppress the size and position of the minimum opening diameter portion 46 from being dispersed among the plurality of through holes 40. Therefore, when the vapor deposition layer 92 is formed so as to overlap the electrode 93 on the substrate 91 as shown in FIG. 19, it is possible to suppress the variation in the size and position of the vapor deposition layer 92 with respect to the size and position of the electrode 93. Can be done. This can also contribute to reducing the margins considered in the design of the vapor deposition substrate 90.

By reducing the margins considered in the design of the thin-film deposition substrate 90, the pixel density of the thin-film deposition substrate 90 can be increased. Further, when the pixel density of the vapor-deposited substrate 90 is constant, the area of the electrode 93 can be expanded while preventing interference between adjacent pixels by reducing the margin. As a result, the ratio of the area of the vapor-deposited layer 92 that overlaps with the electrode 93 can be increased. This leads to an improvement in the luminous efficiency of the vapor deposition layer 92 when the vapor deposition layer 92 is a light emitting layer. Thereby, the brightness of the thin-film deposition layer 92 can be increased and the life of the thin-film deposition layer 92 can be extended.

Next, the embodiments of the present disclosure will be described in more detail with reference to Examples, but the embodiments of the present disclosure are not limited to the description of the following Examples as long as the gist thereof is not exceeded.

(Example 1)
First, a metal plate 30 having a thickness of 30 μm and made of an iron alloy containing 34% by mass or more and 38% by mass or less of nickel was prepared. Next, as shown in FIG. 10 described above, the first resist layer 51 was formed on the first surface 31 of the metal plate 30. Specifically, first, SC500, which is a novolak-based positive resist, was applied to the first surface 31 of the metal plate 30. Subsequently, the positive resist was heated at 140 ° C. for 600 seconds to obtain a first resist layer 51. Then, the first resist layer 51 was exposed and developed to form the exposed region 53 shown in FIG. Subsequently, the metal plate 30 was etched from the first surface 31 side using the first resist layer 51 as a mask to form the first recess 50. The opening dimension S2 of the first recess 50 was 5.0 μm, the depth H5 of the first recess 50 was 2.3 μm, and the pitch of the first recess 50 was 8.0 μm.

Subsequently, the first recess 50 was filled with the filler 52, and the filler 52 was fired. SC500 was used as the filler 52. The firing temperature and firing time of the filler 52 were 140 ° C. and 600 seconds.

Subsequently, in a state where the resist layer is not provided on the second surface 32 of the metal plate 30, a second etching step of etching the metal plate 30 from the second surface 32 side is performed, and the through hole 40 is formed in the metal plate 30. Was formed. As the etching solution, a solution containing ferric chloride solution and hydrochloric acid was used. The temperature of the etching solution was 45 ° C. The etching time was determined based on the etching condition data acquired in advance so that the second surface opening size S3 of the through hole 40 was larger than the first surface opening size S2 by 1 μm or more.

Subsequently, the filler 52 and the first resist layer 51 were removed. The result of observing the cross section of the through hole 40 of the vapor deposition mask 20 obtained in this manner is shown in FIG. As a device for observing the cross section of the through hole 40, a scanning electron microscope ULTRA55 manufactured by ZEISS was used. In the example shown in FIG. 23, minute irregularities having a depth or height of 100 nm or less were observed on the first wall surface 43 and the second wall surface 44 of the wall surface 41 of the through hole 40.

(Example 2)
A through hole 40 was produced in the same manner as in Example 1 except that the etching time in the second etching step was longer than that in Example 1. Further, the cross section of the through hole 40 of the vapor deposition mask 20 was observed in the same manner as in the case of Example 1. The results are shown in FIG.

(Example 3)
The through hole 40 was produced in the same manner as in Example 1 except that the etching time in the second etching step was longer than that in Example 2. Further, the cross section of the through hole 40 of the vapor deposition mask 20 was observed in the same manner as in the case of Example 1. The results are shown in FIG.

10 Thin-film deposition mask device 15 Frame 20 Thin-film deposition mask 201 First surface 202 Second surface 21 Ear part 22 Intermediate part 23 Effective area 24 Peripheral area 30 Metal plate 31 First surface 32 Second surface 35 Shielding part 40 Through hole 41 Wall surface 411 1 end 412 2nd end 43 1st wall surface 44 2nd wall surface 45 Protruding end 46 Minimum opening diameter 50 1st recess 51 1st resist layer 52 Filling material 53 Exposed area 55 2nd recess 56 2nd resist layer 57 Gap 58 Exposed area 80 Thin-film equipment 81 Thin-film source 82 Thin-film material 83 Heater 85 Magnet 90 Thin-film substrate 91 Substrate 92 Thin-film layer 93 Electrode

Claims (8)

A metal plate having a thickness of 10 μm or less, including a first surface and a second surface located on the opposite side of the first surface, and a through hole, is provided.
The through hole has a wall surface including a first end which is an end on the first surface and a second end which is an end on the second surface.
The wall surface includes a minimum opening diameter portion located between the first end and the second end in the thickness direction of the metal plate and having the smallest opening diameter.
In the thickness direction of the metal plate, the distance between the minimum opening diameter and the first end is 2.0 μm or less.
A mask in which the second end has a curved cross-sectional shape. The mask according to claim 1, wherein the metal plate has a thickness of 2 μm or less. The mask according to claim 1 or 2, wherein the distance between the minimum opening diameter and the first end is 0.1 μm or more in the thickness direction of the metal plate. The ratio of the distance between the minimum opening diameter portion and the first end in the thickness direction of the metal plate with respect to the thickness of the metal plate is 0.1 or more and 0.4 or less. The mask according to any one item. The mask according to any one of claims 1 to 4, wherein the second surface of the metal plate located between the two through holes is flat. The mask according to any one of claims 1 to 5, wherein the angle formed by the direction in which the straight line passing through the minimum opening diameter portion and the second end extends and the surface direction of the first surface is 80 ° or less. The mask according to any one of claims 1 to 6, wherein the metal plate has an iron alloy containing 34% by mass or more and 38% by mass or less of nickel. The mask according to any one of claims 1 to 7, wherein the minimum opening size of the through hole is 50 μm or less.