JPWO2017179677A1 - Metal mask for vapor deposition - Google Patents

Abstract

  In the metal mask for vapor deposition, the elements of the metal mask for vapor deposition that define each mask hole are composed of two first mask elements facing each other in the first direction and two second mask elements facing each other in the second direction. Composed. In the cross section orthogonal to the first direction, the ratio of the minimum value in the thickness of the first mask element to the maximum value in the thickness of the second mask element is 70% or more. In each mask hole, the width of the mask hole in the cross section orthogonal to the first direction is the mask hole width, and in the thickness of the second mask element with respect to the minimum value of the mask hole width between the first opening and the second opening. The ratio of maximum values is 41% or more.

Description

  The present invention relates to a metal mask for vapor deposition.

  An organic EL display is known as one of display devices manufactured using a vapor deposition method. The organic layer provided in the organic EL display is a deposit of organic molecules sublimated in the vapor deposition process. The metal mask used in the vapor deposition process has a plurality of mask holes, and each mask hole is a passage through which sublimated organic molecules pass.

  Each mask hole penetrates the metal mask along the thickness direction. In a plan view opposite to the surface where the plurality of mask holes are opened, each mask hole defines a rectangular region, and the plurality of mask holes are arranged in, for example, a staggered arrangement (see, for example, Patent Document 1).

JP 2004-281339 A

  By the way, the width between adjacent mask holes may have different sizes in the extending direction of the mask holes and in the direction intersecting with the extending direction. A relatively small portion in the width between the mask holes is a weak portion having a lower strength than other portions in the metal mask. In a metal mask having a thickness of less than 1 mm, when such fragile portions and mask holes are alternately repeated one by one along one direction, a continuous fold occurs along the direction in which the fragile portions are arranged in the metal mask. There is a case.

These matters are not limited to the metal mask for vapor deposition used for the manufacture of display devices including organic EL displays, but also the metal for vapor deposition used for vapor deposition of functional layers provided for various devices and the formation of wiring provided for various devices. It is common to masks. In addition, such a matter also applies to a metal mask in which a plurality of mask holes are arranged in a lattice shape in a plan view facing one surface where a plurality of mask holes are opened, or a configuration in which each mask hole has a substantially square shape. It is common.
An object of this invention is to provide the metal mask for vapor deposition which enabled it to suppress the fold which continues along the direction where a mask hole is located in a line.

  The metal mask for vapor deposition for solving the said subject is a metal mask for vapor deposition provided with the several mask hole lined up along a 1st direction and the 2nd direction orthogonal to the said 1st direction. The metal mask for vapor deposition includes a first surface and a second surface, and each mask hole has a first opening opened in the first surface and a second opening opened in the second surface. The element of the metal mask for vapor deposition that defines each mask hole is composed of two first mask elements facing each other in the first direction and two second mask elements facing each other in the second direction. The The first mask element and the mask hole are alternately repeated one by one along the first direction, and the second mask element and the mask hole are one along the second direction. Repeated alternately. The width of the first mask element along the first direction is smaller than the width of the second mask element along the second direction. In the cross section orthogonal to the first direction, the ratio of the minimum value in the thickness of the first mask element to the maximum value in the thickness of the second mask element is 70% or more. In each mask hole, the width of the mask hole in a cross section orthogonal to the first direction is the mask hole width, and the mask hole width in the first opening is larger than the mask hole width in the second opening. Is also small. The ratio of the maximum value in the thickness of the second mask element to the minimum value of the mask hole width between the first opening and the second opening is 41% or more.

  According to the above configuration, in a cross section orthogonal to the first direction, the difference between the maximum value in the thickness of the second mask element and the minimum value in the thickness of the first mask element is smaller than 30%. Variations in thickness within the metal mask for vapor deposition can be suppressed. Therefore, the difference in strength between the portion where the first mask elements are continuous and the other portions in the metal mask for vapor deposition can be suppressed to such an extent that the occurrence of folding in the portions where the first mask elements are continuous is suppressed.

  In the metal mask for vapor deposition, the length of the first mask element along the second direction increases as the mask hole width increases. On the other hand, the thickness of the first mask element is roughly determined by the maximum value in the thickness of the second mask element sandwiching the first mask element in the second direction, and the thickness of the first mask element increases as the maximum value increases. growing.

  In this regard, according to the above configuration, since the ratio of the maximum value in the thickness of the second mask element to the minimum value of the mask hole width is 41% or more, the strength of each first mask element is the metal mask for vapor deposition. Compared with the other portions in FIG. 5, the size is such that the folding does not concentrate on the first mask element.

  As a result, it is possible to suppress the occurrence of continuous folding along the direction in which the mask holes are arranged in the metal mask for vapor deposition.

  In the metal mask for vapor deposition, the plurality of mask holes are arranged at a constant pitch along the first direction, a ratio of the maximum value to the pitch is 6% or more, and the maximum value is the second direction. It is preferable that the maximum value in the thickness of the first mask element in a cross section orthogonal to the first mask element.

  The pitch along the first direction is a minimum unit between elements constituting the metal mask for vapor deposition, that is, the first mask element and the space. Of these, the first mask element is a portion that is maintained at a predetermined size regardless of the size of the organic layer formed by the metal mask for vapor deposition. The size of the first mask element is determined by, for example, the size of a peripheral circuit and the like, and is a portion that is the minimum size in order to increase the light emission efficiency in the organic EL display. On the other hand, the space included in the pitch is a portion whose size changes depending on the resolution required for the organic EL display.

  In this regard, in the metal mask for vapor deposition, even if the size of the pitch is changed, that is, the size of the space included in the pitch is changed, the maximum value in the thickness of the first mask element is not less than a predetermined value. Maintained. Therefore, generation | occurrence | production of the folding in a 1st mask element is suppressed among the metal masks for vapor deposition.

  In the metal mask for vapor deposition, the mask hole width is a second mask hole width that is a mask hole width along the second direction, and the width of the mask hole in a cross section orthogonal to the second direction is the first direction. The first mask hole width at the first opening is smaller than the first mask hole width at the second opening, and from the first opening. The ratio of the maximum value in the thickness of the first mask element to the minimum value of the first mask hole width until the second opening is preferably 7% or more.

In the metal mask for vapor deposition, the larger the maximum value in the thickness of the first mask element that defines the mask hole in the first direction with respect to the width of the mask hole that is a space extending along the first direction, the larger the metal for vapor deposition. The strength of the mask is increased.
In this respect, according to the above configuration, since the ratio of the maximum value in the thickness of the first mask element to the minimum value of the first mask hole width is 7% or more, the strength of each first mask element is for deposition. Compared to other portions of the metal mask, the size is such that the folding is not more concentrated on the first mask element.

  In the metal mask for vapor deposition, the plurality of mask holes may be arranged in a staggered arrangement as viewed from a direction orthogonal to the direction in which the metal mask for vapor deposition spreads.

  According to the above configuration, in the metal mask for vapor deposition in which a plurality of mask holes are arranged in a staggered arrangement, it is possible to suppress the continuous folding along the direction in which the mask holes are arranged.

  According to the present invention, it is possible to suppress continuous folding along the direction in which the mask holes are arranged.

The fragmentary perspective view which shows the partial perspective structure in one Embodiment which actualized the metal mask for vapor deposition of this invention. The partial top view which shows the partial planar structure of the metal mask for vapor deposition in the planar view facing 1st surface. The fragmentary sectional view which shows typically a part of cross section orthogonal to a 1st direction. The fragmentary sectional view which shows typically a part of cross section orthogonal to a 1st direction. The fragmentary sectional view which shows typically a part of cross section orthogonal to a 2nd direction. Process drawing for demonstrating the formation process of the resist layer in the manufacturing method of the metal mask for vapor deposition. Process drawing for demonstrating the patterning process of the resist layer in the manufacturing method of the metal mask for vapor deposition. The partial top view which shows the partial planar structure of the resist pattern in the planar view facing the 1st surface of the base material for metal masks. The partial top view which shows the partial planar structure of the resist pattern in the planar view facing the 2nd surface of the base material for metal masks. Process drawing for demonstrating the process of etching the base material for metal masks from the 1st surface in the manufacturing method of the metal mask for vapor deposition. Process drawing for demonstrating the process of etching the base material for metal masks from the 2nd surface in the manufacturing method of the metal mask for vapor deposition. FIG. 5 is a partial cross-sectional view schematically showing a part of a cross section orthogonal to a first direction in Example 1 to Example 3. The fragmentary sectional view which shows typically a part of cross section orthogonal to the 1st direction in the comparative examples 1, 3, and 5. FIG. The fragmentary sectional view which shows typically a part of cross section orthogonal to the 1st direction in the comparative examples 2, 4, and 6. FIG. The top view which shows the planar structure seen from the direction which opposes the 1st surface in the metal mask for vapor deposition of a modification.

  With reference to FIGS. 1 to 14, an embodiment embodying the metal mask for vapor deposition of the present invention will be described. Below, the structure of the metal mask for vapor deposition, the manufacturing method of the metal mask for vapor deposition, and an Example are demonstrated in order. In addition, the metal mask for vapor deposition demonstrated below is a metal mask for vapor deposition used for manufacture of an organic electroluminescent display provided with a some organic layer.

[Configuration of metal mask for evaporation]
With reference to FIGS. 1 to 5, the configuration of the metal mask for vapor deposition will be described.
As shown in FIG. 1, the vapor deposition metal mask 10 includes a first surface 10a and a second surface 10b. The metal mask for vapor deposition 10 has a plate shape extending along the first direction D1 and having a predetermined width along a second direction D2 orthogonal to the first direction D1.

  The metal mask for vapor deposition 10 includes a plurality of mask holes 11 arranged along the first direction D1 and the second direction D2. When viewed from the direction facing the first surface 10a, the first surface 10a is partitioned into a mask region R1 in which a plurality of mask holes 11 are formed and a peripheral region R2 surrounding the mask region R1. . The mask region R1 is a region that has been processed to form a plurality of mask holes 11, and the peripheral region R2 is a region that has not been processed.

  A plurality of mask regions R1 may be defined on the first surface 10a at predetermined intervals along the first direction D1, or at predetermined intervals along each of the first direction D1 and the second direction D2. A plurality of mask regions R1 may be partitioned at intervals.

  The metal mask 10 for vapor deposition is made of metal and is preferably made of Invar. The material for forming the vapor deposition metal mask 10 may be a metal other than Invar. Of the metal mask 10 for vapor deposition, the thickness T in the peripheral region R2 is preferably 20 μm or more and 50 μm or less, for example.

  FIG. 2 shows a planar structure of the vapor deposition metal mask 10 as viewed from the direction facing the first surface 10a.

  As shown in FIG. 2, in the metal mask for vapor deposition 10, the elements of the metal mask for vapor deposition 10 that define each mask hole 11 include two first mask elements 21 that face each other in the first direction D <b> 1 and the second direction. It is comprised from the 2nd 2nd mask element 22 which mutually opposes in D2.

  In the metal mask 10 for vapor deposition, the first mask elements 21 and the mask holes 11 are alternately repeated one by one along the first direction D1, and the second mask elements 22 and the mask holes 11 are second. It is repeated alternately one by one along the direction D2.

  The width that the first mask element 21 has along the first direction D1 is the first width W1, and the width that the second mask element 22 has along the second direction D2 is the second width W2. The first width W1 of the first mask element 21 is smaller than the second width W2 of the second mask element 22.

  The metal mask for vapor deposition 10 extends along a plane defined by the first direction D1 and the second direction D2, and the plurality of mask holes 11 are staggered when viewed from a direction orthogonal to the direction in which the metal mask for vapor deposition 10 spreads. Are lined up. In other words, when viewed from the direction facing the first surface 10a, the plurality of mask holes 11 are arranged in a staggered arrangement.

  In a plan view facing the first surface 10a, each mask hole 11 defines a rectangular region, and the width of each mask hole 11 along the first direction D1 is that the mask hole 11 extends in the second direction D2. Greater than the width you have along. The plurality of mask holes 11 are arranged at a constant first pitch P1 along the first direction D1.

  In the plurality of mask holes 11, the plurality of mask holes 11 arranged along the first direction D1 form one row. In the plurality of mask holes 11 constituting each row, the positions in the first direction D1 overlap each other. On the other hand, in the rows adjacent to each other in the second direction D2, the positions in the plurality of mask holes 11 constituting the other row with respect to the positions in the first direction D1 in the plurality of mask holes 11 constituting the one row. The position in one direction D1 is shifted by ½ pitch. Among the plurality of mask holes 11, the mask holes 11 whose positions in the first direction D1 overlap are arranged at a constant second pitch P2 along the second direction D2. The second pitch P2 is a value equal to the first pitch P1. The first pitch P1 and the second pitch P2 are generally equal to each other following the pixel shape.

  In the plurality of mask holes 11 arranged in a staggered arrangement, one first mask element 21 located between two mask holes 11 adjacent in the first direction D1 is used for vapor deposition that partitions each of the two mask holes 11. It functions as an element of the metal mask 10. In addition, between the two mask holes 11 adjacent in the second direction D2, a part of the metal mask for vapor deposition 10 functioning as the second mask element 22 for one mask hole 11 and the other mask hole. 11 and a part of the portion functioning as the second mask element 22 with respect to 11 overlap each other.

  In the plurality of mask holes 11 arranged in a staggered arrangement, the positional deviation in the first direction D1 of the mask holes 11 may be smaller than ½ pitch in the rows adjacent to each other in the second direction D2. However, it may be larger than 1/2 pitch. Moreover, in each mask hole 11, the width | variety which has along the 1st direction D1 and the width | variety which has along the 2nd direction D2 may mutually be equal.

  FIG. 3 shows a cross-sectional structure perpendicular to the first direction D1 in the vapor deposition metal mask 10 and passing through the center of the first mask element 21 in the first direction D1. FIG. 3 shows a cross-sectional structure taken along line II of FIG.

  As shown in FIG. 3, in the cross section orthogonal to the first direction D1, the thickness of the first mask element 21 has a minimum value T1m, and the thickness of the second mask element 22 has a maximum value T2M. .

In the cross section orthogonal to the first direction D1, it is preferable that the minimum value T1m in the thickness of the first mask element 21 is 12.5 μm or more. The ratio of the minimum value T1m in the thickness of the first mask element 21 to the maximum value T2M in the thickness of the second mask element 22 is 70% or more. That is, the minimum value T1m in the thickness of the first mask element 21 and the maximum value T2M in the thickness of the second mask element 22 satisfy the following expression (1).
T1m / T2M × 100 ≧ 70 (1)

  According to the metal mask 10 for vapor deposition, the thickness of the first mask element 21 is ensured to be 12.5 μm or more in the cross section orthogonal to the first direction D1. Therefore, there is a difference in strength between the continuous portion of the first mask element 21 and the other portion in the metal mask for vapor deposition 10 to such an extent that the folding of the continuous portion of the first mask element 21 is suppressed. More suppressed.

  Further, the thickness in the deposition metal mask 10 is set so that the difference between the maximum value T2M in the thickness of the second mask element 22 and the minimum value T1m in the thickness of the first mask element 21 is smaller than 30%. Variation in length is suppressed.

  Therefore, in the vapor deposition metal mask 10, there is a difference in strength between the portion where the first mask element 21 is continuous and the other portion in the metal mask for vapor deposition 10 to such an extent that folding is suppressed at the portion where the first mask element 21 is continuous. It can be suppressed. As a result, it is possible to suppress the folding metal mask 10 from being bent along the direction in which the mask holes 11 are arranged, in particular, the folding along the direction in which the first mask elements 21 are arranged.

  Each mask hole 11 has a first opening 11a opened in the first surface 10a and a second opening 11b opened in the second surface 10b. Each mask hole 11 includes a first hole element 11c including a first opening 11a and a second hole element 11d including a second opening 11b. The first hole element 11c and the second hole element 11d are formed by vapor deposition. The metal mask 10 is continuous in the thickness direction. A portion where the first hole element 11c and the second hole element 11d are continuous is a continuous element 11e.

  In each mask hole 11, the width of the mask hole 11 in the cross section orthogonal to the first direction D1, and the width of the mask hole 11 along the second direction D2 is the second mask hole width Wm2. The second mask hole width Wm2 at the first opening 11a is smaller than the second mask hole width Wm2 at the second opening 11b.

  The second mask hole width Wm2 in the first hole element 11c is the largest in the first opening 11a and gradually decreases toward the continuous element 11e, and the second mask hole width Wm2 in the second hole element 11d is the second opening 11b. And gradually decreases toward the continuous element 11e. That is, in each mask hole 11, the second mask hole width Wm2 in the continuous element 11e is the smallest. In addition, the length along the thickness direction of the vapor deposition metal mask 10 in the first hole element 11c is smaller than the length along the thickness direction of the vapor deposition metal mask 10 in the second hole element 11d.

The ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 is 41% or more. That is, the minimum value Wmm2 of the second mask hole width Wm2 and the maximum value T2M in the thickness of the second mask element 22 satisfy the following expression (2).
T2M / Wmm2 × 100 ≧ 41 (2)

  In the metal mask 10 for vapor deposition, the length of the 1st mask element 21 along the 2nd direction D2 becomes large, so that the 2nd mask hole width Wm2 is large. On the other hand, the thickness of the first mask element 21 is roughly determined by the maximum value T2M in the thickness of the second mask element 22 sandwiching the first mask element 21 in the second direction D2, and the larger the maximum value T2M, the first The thickness of the mask element 21 is increased.

  In this regard, in the metal mask for vapor deposition 10 described above, since the ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 is 41% or more, each first mask The strength of the element 21 is such that the folding does not concentrate on the first mask element 21 as compared with other portions of the metal mask 10 for vapor deposition.

  As shown in FIG. 4, the surface defining the second hole element 11d is the second inner peripheral surface 11dp, and in the cross section orthogonal to the first direction D1, the second inner peripheral surface 11dp includes the first arc-shaped element dp1, A second arc-shaped element dp2 and an inflection element dp3 are included. On the second inner peripheral surface 11dp, the two first arc-shaped elements dp1 are opposed in the second direction D2, the two second arc-shaped elements dp2 are opposed in the second direction D2, and the two inflection elements dp3 are the first Opposing in the two directions D2.

  The first arc-shaped element dp1 includes a continuous element 11e, and the second arc-shaped element dp2 includes a second opening 11b. The radius of curvature of the first arc-shaped element dp1 and the radius of curvature of the second arc-shaped element dp2 are different from each other, and the radius of curvature of the first arc-shaped element dp1 is larger than the radius of curvature of the second arc-shaped element dp2. The inflection element dp3 is a part where the first arc-shaped element dp1 and the second arc-shaped element dp2 are connected. Each of the first arc-shaped element dp1 and the second arc-shaped element dp2 has a curvature such that the center of the curvature of each arc-shaped element is located outside the deposition metal mask 10.

  The surface defining the first hole element 11c is the first inner peripheral surface 11cp, and the first inner peripheral surface 11cp includes a first opening 11a and a continuous element 11e in a cross section orthogonal to the first direction D1. It has an arcuate element cp1. In the first inner peripheral surface 11cp, the two first arc-shaped elements cp1 face each other in the second direction D2. The first arc-shaped element cp <b> 1 has a curvature such that the center of curvature of the first arc-shaped element cp <b> 1 is located outside the deposition metal mask 10.

  FIG. 5 shows a cross-sectional structure perpendicular to the second direction D2 in the vapor deposition metal mask 10 and passing through the center of the first mask element 21 in the second direction D2. FIG. 5 shows a cross-sectional structure taken along line II-II in FIG.

As shown in FIG. 5, in the cross section orthogonal to the second direction D2, the first mask element 21 has a maximum value T1M. The ratio of the maximum value T1M in the thickness of the first mask element 21 to the first pitch P1 along the first direction D1 described above is 6% or more. That is, the first pitch P1 along the first direction D1 and the maximum value T1M of the first mask element 21 satisfy the following expression (3).
T1M / P1 × 100 ≧ 6 Formula (3)

  The first pitch P <b> 1 along the first direction D <b> 1 is a minimum unit of the elements constituting the metal mask for vapor deposition 10, that is, the first mask element 21 and the space. Among these, the 1st mask element 21 is a part maintained by the predetermined | prescribed magnitude | size irrespective of the magnitude | size of the organic layer formed with the metal mask 10 for vapor deposition. The size of the first mask element 21 is determined by, for example, the size of a peripheral circuit or the like, and is a portion that is set to a minimum size in order to increase the light emission efficiency in the organic EL display. On the other hand, the space included in the first pitch P1 is a portion whose size changes depending on the resolution required for the organic EL display.

  In this regard, in the vapor deposition metal mask 10, even if the size of the first pitch P1 changes, that is, the size of the space included in the first pitch P1, the thickness of the first mask element 21 changes. The maximum value T1M is maintained at a predetermined value or more. Therefore, the generation | occurrence | production of the folding in the 1st mask element 21 is suppressed among the metal masks 10 for vapor deposition.

  In the cross section orthogonal to the second direction D2, the first mask element 21 has a substantially pentagonal shape. Therefore, the first mask element 21 has a maximum value T1M in thickness at the vertex having the largest distance from the side along the first surface 10a.

  In each mask hole 11, the width of the mask hole 11 in the cross section orthogonal to the second direction D2, and the width of the mask hole 11 along the first direction D1 is the first mask hole width Wm1. The first mask hole width Wm1 at the first opening 11a is smaller than the first mask hole width Wm1 at the second opening 11b.

The first mask hole width Wm1 has a minimum value Wmm1 in the middle of the direction from the first opening 11a to the second opening 11b. The ratio of the maximum value T1M in the thickness of the first mask element 21 to the minimum value Wmm1 of the first mask hole width Wm1 is 7% or more. That is, the minimum value Wmm1 of the first mask hole width Wm1 and the maximum value T1M in the thickness of the first mask element 21 satisfy the following expression (4).
T1M / Wmm1 × 100 ≧ 7 Formula (4)

  In the metal mask 10 for vapor deposition, the maximum value T1M in the thickness of the first mask element 21 that defines the mask hole 11 in the first direction D1 with respect to the width of the mask hole 11 that is a space extending along the first direction D1. The larger the is, the higher the strength of the metal mask for vapor deposition 10 is.

  In this regard, in the metal mask for vapor deposition 10, since the ratio of the maximum value T1M in the thickness of the first mask element 21 to the minimum value Wmm1 of the first mask hole width Wm1 is 7% or more, each first mask element 21 Compared to other portions of the metal mask for vapor deposition 10, the strength of the folds is such that the folding is not concentrated on the first mask element 21.

  In addition, formation of the organic layer with respect to the film-forming target using such a metal mask 10 for vapor deposition is performed as follows. Below, the 1st direction D1 and the 2nd direction D2 in the metal mask 10 for vapor deposition are demonstrated corresponding to the 1st direction D1 and the 2nd direction D2 in the film-forming object after film-forming.

  For example, when an organic layer is formed, first, a blue organic layer is formed on a deposition target using the vapor deposition metal mask 10. Next, using another metal mask for vapor deposition, the green organic layer is disposed in a portion between the blue organic layer in the second direction D2 and adjacent to one blue organic layer in the second direction D2. The red organic layer is formed so as to be aligned along the first direction D1.

  Also, for example, first, a blue organic layer is formed on the film formation target using the vapor deposition metal mask 10. Next, using another metal mask for vapor deposition, the green organic layer is disposed in a portion between the blue organic layer in the second direction D2 and adjacent to one blue organic layer in the second direction D2. The red organic layer is formed so as to be aligned along the second direction D2.

[Method of manufacturing metal mask for vapor deposition]
With reference to FIGS. 6 to 11, a method of manufacturing the metal mask 10 for vapor deposition will be described. Each of FIGS. 6 to 11 shows a cross-sectional structure corresponding to a cross section taken along the line II of FIG. 2 and corresponding to each manufacturing process.

  As shown in FIG. 6, when manufacturing the metal mask for vapor deposition 10, first, a metal mask substrate 31 for forming the metal mask for vapor deposition 10 is prepared. The metal mask base material 31 is preferably made of Invar, and the thickness of the metal mask base material 31 is preferably 20 μm or more and 50 μm or less, for example.

  The metal mask base material 31 has a first surface 31a and a second surface 31b that is a surface opposite to the first surface 31a. The first surface 31 a of the metal mask substrate 31 corresponds to the first surface 10 a of the vapor deposition metal mask 10, and the second surface 31 b of the metal mask substrate 31 is the second surface 10 b of the vapor deposition metal mask 10. It corresponds to.

  A first resist layer 32 is formed on the first surface 31a of the metal mask substrate 31, and a second resist layer 33 is formed on the second surface 31b. Each resist layer may be formed on the metal mask substrate 31 by applying a dry film resist, or may be formed by applying a coating liquid containing a resist layer forming material on the surface. . The material for forming the resist layer is preferably a negative resist material, but may be a positive resist material.

  As shown in FIG. 7, the first resist pattern 34 is formed by removing a part of the first resist layer 32 from the first surface 31 a of the metal mask base material 31. Further, a part of the second resist layer 33 is removed from the second surface 31 b of the metal mask base material 31, thereby forming the second resist pattern 35. When forming each resist pattern, if it is a negative resist layer, only the portion of the resist layer that remains on the metal mask substrate 31 as a resist pattern is exposed. Then, the exposed resist layer is developed. In the case of a positive resist layer, only the portion of the resist layer that is removed from the metal mask base material 31 may be exposed.

  It should be noted that the exposure of the first resist layer 32 and the exposure of the second resist layer 33 may be performed simultaneously or separately. In addition, the development of the first resist layer 32 and the development of the second resist layer 33 may be performed simultaneously or individually.

  The first resist pattern 34 has a plurality of first pattern elements 34a and a plurality of second pattern elements 34b. The first resist pattern 34 is a resist pattern for forming the first hole elements 11 c in the plurality of mask holes 11 on the metal mask base material 31. Among these, each 1st pattern element 34a is a pattern element for dividing the 1st mask element 21 in the base material 31 for metal masks, and each 2nd pattern element 34b is 2nd on the base material 31 for metal masks. It is a pattern element for partitioning the mask element 22.

  The second resist pattern 35 has a plurality of first pattern elements 35a and a plurality of second pattern elements 35b. The second resist pattern 35 is a resist pattern for forming the second hole element 11 d in the plurality of mask holes 11 on the metal mask substrate 31. Similar to the first resist pattern 34, each first pattern element 35a is a pattern element for partitioning the first mask element 21 on the metal mask substrate 31, and each second pattern element 35b is a metal mask base. This is a pattern element for dividing the second mask element 22 into the material 31.

  FIG. 8 shows a planar structure of the first resist pattern 34 in a plan view facing the first surface 31a of the metal mask substrate 31. As shown in FIG. In FIG. 8, dots are added to the first resist pattern 34 for the sake of convenience in understanding the shape of the first resist pattern 34.

  As shown in FIG. 8, in a plan view facing the first surface 31a of the metal mask base material 31, the first pattern element 34a extends along the second direction D2 and is constant along the first direction D1. They are lined up at intervals. In the first direction D1, the repeated pitch of the first pattern elements 34a is substantially equal to the repeated pitch of the first mask elements 21 along the first direction D1 in the deposition metal mask 10.

  The second pattern element 34b extends along the first direction D1, and the two second pattern elements 34b adjacent in the second direction D2 are spaced apart from each other by the length of the first pattern element 34a. Yes. The width W34a of the first pattern element 34a along the first direction D1 is smaller than the width W34b of the second pattern element 34b along the second direction D2.

  FIG. 9 shows a planar structure of the second resist pattern 35 in a plan view facing the second surface 31 b of the metal mask base material 31. In FIG. 9, dots are added to the second resist pattern 35 for the sake of convenience in understanding the shape of the second resist pattern 35.

  As shown in FIG. 9, in a plan view facing the second surface 31b of the metal mask base material 31, the first pattern elements 35a extend along the second direction D2, and are spaced apart along the first direction D1. Are lined up. In the first direction D1, the repeated pitch of the first pattern elements 35a is substantially equal to the repeated pitch of the first mask elements 21 along the first direction D1 in the vapor deposition metal mask 10.

  The second pattern element 35b extends along the first direction D1, and the two second pattern elements 35b adjacent in the second direction D2 are spaced apart from each other by the length of the first pattern element 35a. Yes. The second pattern element 35b has a gap 35c extending along the first direction D1, and the gap 35c is located at the center of the second direction D2 in each second pattern element 35b.

  The width W35c of the gap 35c along the second direction D2 is greater than the distance between the two second pattern elements 35b in the second direction D2, that is, the width W35a2 of the first pattern element 35a along the second direction D2. Is also small. Further, the width W35a1 of the first pattern element 35a along the first direction D1 is smaller than the width W35b of the second pattern element 35b along the second direction D2.

  The first pattern element 35a is located between the second pattern elements 35b adjacent in the second direction D2, and is connected to the two second pattern elements 35b sandwiching the first pattern element 35a in the second direction D2. ing.

  As shown in FIG. 10, the metal mask base material 31 is etched from the first surface 31 a using the first resist pattern 34. FIG. 10 shows a state of the metal mask base material 31 during the etching of the metal mask base material 31 from the first surface 31a. If the metal mask substrate 31 is made of Invar, for example, ferric chloride solution can be used as the etching solution for the metal mask substrate 31.

  When the metal mask base material 31 is etched from the first surface 31a, the surface of the second resist pattern 35 that is in contact with the metal mask base material 31 before the etching of the metal mask base material 31 is started. A second protective layer 36 is formed on the opposite surface.

  The second protective layer 36 is a layer for preventing the metal mask base material 31 from being etched from the second surface 31b when the metal mask base material 31 is etched from the first surface 31a. The material for forming the second protective layer 36 may be any material that is resistant to the etching solution of the metal mask substrate 31.

  After the etching of the metal mask substrate 31 using the first resist pattern 34 is completed, the second protective layer 36 is peeled off from the second resist pattern 35 and the first resist 31a is removed from the first surface 31a of the metal mask substrate 31. The pattern 34 is peeled off.

  As shown in FIG. 11, the metal mask base material 31 is etched from the second surface 31 b using the second resist pattern 35. FIG. 11 shows the state of the metal mask base material 31 during the etching of the metal mask base material 31 from the second surface 31b. If the metal mask substrate 31 is made of Invar, for example, ferric chloride solution can be used as the etching solution for the metal mask substrate 31.

  When the metal mask base material 31 is etched from the second surface 31b, the first protective layer 37 is formed on the first surface 31a of the metal mask base material 31 before the etching of the metal mask base material 31 is started. Form.

  The first protective layer 37 is a layer for preventing the metal mask base material 31 from being etched from the first surface 31a when the metal mask base material 31 is etched from the second surface 31b. The formation material of the 1st protective layer 37 should just be the material which has the tolerance with respect to the etching solution of the base material 31 for metal masks.

  After the etching of the metal mask substrate 31 using the second resist pattern 35 is completed, the first protective layer 37 is peeled off from the first surface 31a of the metal mask substrate 31, and the second resist pattern is removed from the second surface 31b. Remove 35. Thereby, the metal mask 10 for vapor deposition can be obtained.

  When the metal mask base 31 is etched from the second surface 31b, the portion of the metal mask base 31 that is exposed from the second resist pattern 35 has a higher etching rate. Therefore, in the thickness direction of the metal mask base material 31, the metal mask base material 31 is located between the second pattern elements 35 b rather than the etching rate in the portion overlapping the gap 35 c of the second pattern element 35 b. The etching rate at the part is high.

  Thereby, the metal mask base material 31 is formed with a portion with a large etching amount and a portion with a small etching amount. As a result, in the cross section orthogonal to the first direction D1, the ratio of the minimum value T1m in the thickness of the first mask element 21 to the maximum value T2M in the thickness of the second mask element 22 is 70% or more, and The metal mask for vapor deposition 10 in which the ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the two mask hole widths Wm2 is 41% or more can be obtained.

[Example]
Examples and Comparative Examples will be described with reference to FIGS. In Examples 1 to 3 described below, the thicknesses of the metal mask base materials used for manufacturing the metal mask for vapor deposition of each example are different from each other. However, the ratio of the minimum value T1m to the maximum value T2M in each evaporation metal mask, the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2, the ratio of the maximum value T1M to the first pitch P1, and the first The ratio of the maximum value T1M to the minimum value Wmm1 of the mask hole width Wm1 is a substantially equal value between the examples. Therefore, the metal mask for vapor deposition of Example 1- Example 3 is demonstrated with reference to one figure for convenience.

  Moreover, in Comparative Examples 1, 3, and 5, the thicknesses of the metal mask base materials used for manufacturing the vapor deposition metal masks of the respective comparative examples are different from each other. However, the ratio of the minimum value T1m to the maximum value T2M in each evaporation metal mask, the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2, the ratio of the maximum value T1M to the first pitch P1, and the first The ratio of the maximum value T1M to the minimum value Wmm1 of the mask hole width Wm1 is a substantially equal value among the comparative examples. Therefore, the metal mask for vapor deposition of Comparative Examples 1, 3, and 5 will be described with reference to one drawing for convenience.

  Further, in Comparative Examples 2, 4, and 6, the thicknesses of the metal mask base materials used for manufacturing the evaporation metal masks of the respective comparative examples are different from each other. However, the ratio of the minimum value T1m to the maximum value T2M in each evaporation metal mask, the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2, the ratio of the maximum value T1M to the first pitch P1, and the first The ratio of the maximum value T1M to the minimum value Wmm1 of the mask hole width Wm1 is a substantially equal value among the comparative examples. Therefore, the metal mask for vapor deposition of Comparative Examples 2, 4, and 6 will be described with reference to one drawing for convenience.

[Example 1]
A metal mask base material made of Invar and having a thickness of 30 μm was prepared. A negative resist film is attached to the first surface of the metal mask base material to form a first resist layer on the first surface of the metal mask base material, and the negative dry film resist is used for the metal mask. The 2nd resist layer was formed in the 2nd surface of the base material for metal masks by affixing on the 2nd surface of a base material.

  The first resist layer was patterned to form a first resist pattern having the following shape. In the first resist pattern, the pitch of the first pattern elements along the first direction is 195 μm, the length of the first pattern elements along the first direction is 30.0 μm, and the first pattern along the second direction The length of the pattern element was 33.5 μm. In the first resist pattern, the length of the second pattern element along the second direction was 64.0 μm.

  The second resist layer was patterned to form a second resist pattern having the following shape. In the second resist pattern, the pitch of the first pattern elements along the first direction is 195 μm, the length of the first pattern elements along the first direction is 16.5 μm, and the first pattern along the second direction The length of the pattern element was 58.3 μm. In the second resist pattern, the length of the second pattern element along the second direction was 39.1 μm, and the length of the gap of the second pattern element was 10.3 μm. That is, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction was 14.4 μm.

  And the metal mask for vapor deposition of Example 1 was obtained by etching the base material for metal masks using a ferric chloride liquid. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 195 μm. there were.

  As shown in FIG. 12, in the cross section orthogonal to the first direction D1, the thickness of the first mask element 21 has the minimum value T1m, and the thickness of the second mask element 22 has the maximum value T2M. The minimum value T1m was 12.5 μm and the maximum value T2M was 17.7 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 70.6%. Further, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 6.4%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 42.6 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 41.5%.

  In Example 1, as described above with reference to FIG. 5, it was recognized that the first mask element 21 had a substantially pentagonal shape in the cross section orthogonal to the second direction D2. Further, it was recognized that the first mask element 21 had a maximum value T1M, and the maximum value T1M was recognized to be 12.5 μm. As described above, since the first pitch P1 in which the plurality of mask holes are arranged along the first direction D1 is 195 μm, it is recognized that the ratio of the maximum value T1M to the first pitch P1 is 6.4%. It was.

  Further, in the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 167.9 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 7.4%.

[Example 2]
A metal mask base material made of Invar and having a thickness of 25 μm was prepared. Moreover, the metal mask for vapor deposition of Example 2 was obtained by the same method as Example 1 except having changed the dimension of the 1st resist pattern and the dimension of the 2nd resist pattern as follows. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 162. It was 5 μm.

  In the first resist pattern, the pitch of the first pattern elements along the first direction is 162.5 μm, the length of the first pattern elements along the first direction is 25 μm, and the first along the second direction. The length of the pattern element was 27.9 μm. In the first resist pattern, the length of the second pattern element along the second direction was 53.3 μm.

  In the second resist pattern, the pitch of the first pattern elements along the first direction is 162.5 μm, and the length of the first pattern elements along the first direction is 13.8 μm, along the second direction. The length of the first pattern element was 48.6 μm. In the second resist pattern, the length of the second pattern element along the second direction was 32.6 μm, and the length of the gap of the second pattern element was 8.6 μm. In other words, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction was 12.0 μm.

  As shown in FIG. 12, in the metal mask for vapor deposition 10 of Example 2, the minimum value T1m in the thickness of the first mask element 21 is 10.4 μm in the cross section orthogonal to the first direction D1, and the second mask It was found that the maximum value T2M in the thickness of the element 22 was 14.8 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 70.3%. Further, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 6.4%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 35.8 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 41.3%.

  Furthermore, in the metal mask 10 for vapor deposition of Example 2, it was recognized that the maximum value T1M in the thickness of the 1st mask element 21 is 10.4 micrometer in the cross section orthogonal to the 2nd direction D2. Since the first pitch P1 in which the plurality of mask holes 11 are arranged along the first direction D1 is 162.5 μm, it was recognized that the ratio of the maximum value T1M to the first pitch P1 was 6.4%.

  In the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 139.0 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 7.5%.

[Example 3]
A metal mask base material made of Invar and having a thickness of 20 μm was prepared. Moreover, the metal mask for vapor deposition of Example 3 was obtained by the same method as Example 1 except having changed the dimension of the 1st resist pattern and the dimension of the 2nd resist pattern as follows. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 130 μm. there were.

  In the first resist pattern, the pitch of the first pattern elements along the first direction is 130 μm, the length of the first pattern elements along the first direction is 20 μm, and the first pattern elements along the second direction The length of was 22.3 μm. In the first resist pattern, the length of the second pattern element along the second direction was 42.7 μm.

  In the second resist pattern, the pitch of the first pattern elements along the first direction is 130 μm, the length of the first pattern elements along the first direction is 11 μm, and the first pattern elements along the second direction Was 38.9 μm in length. In the second resist pattern, the length of the second pattern element along the second direction was 26.1 μm, and the length of the gap of the second pattern element was 6.9 μm. In other words, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction was 9.6 μm.

  As shown in FIG. 12, in the metal mask for vapor deposition 10 of Example 3, the minimum value T1m in the thickness of the first mask element 21 is 8.8 μm in the cross section orthogonal to the first direction D1, and the second mask It was found that the maximum value T2M in the thickness of the element 22 was 11.9 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 73.9%. Furthermore, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 6.8%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 28.4 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 41.9%.

  Furthermore, in the metal mask 10 for vapor deposition of Example 3, it was recognized that the maximum value T1M in the thickness of the 1st mask element 21 is 8.8 micrometers in the cross section orthogonal to the 2nd direction D2. Since the first pitch P1 in which the plurality of mask holes 11 are arranged along the first direction D1 is 130 μm, it was recognized that the ratio of the maximum value T2M to the first pitch P1 was 6.8%.

  In the cross section perpendicular to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 112.2 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 7.8%.

[Comparative Example 1]
A metal mask base material made of Invar and having a thickness of 30 μm was prepared. In addition, except that the dimensions of the first resist pattern and the dimensions of the second resist pattern were changed as follows, and the second resist pattern having a pattern element having no gap as the second pattern element was formed. The metal mask for vapor deposition of the comparative example 1 was obtained by the same method as Example 1. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 195 μm. there were.

  In the first resist pattern, the pitch of the first pattern elements along the first direction is 195 μm, the length of the first pattern elements along the first direction is 27.9 μm, and the first pattern along the second direction The length of the pattern element was 36.6 μm. In the first resist pattern, the length of the second pattern element along the second direction was 60.9 μm.

  In the second resist pattern, the pitch of the first pattern elements along the first direction is 195 μm, the length of the first pattern elements along the first direction is 5.2 μm, and the first along the second direction. The length of the pattern element was 76.9 μm. In the second resist pattern, the length of the second pattern element along the second direction was 20.6 μm.

  As shown in FIG. 13, in the vapor deposition metal mask 40 of Comparative Example 1, the thickness of the first mask element 41 has the minimum value T1m in the cross section orthogonal to the first direction D1, and the second mask element. It was observed that the thickness of 42 had a maximum value T2M, a minimum value T1m of 9.7 μm, and a maximum value T2M of 20.8 μm. That is, it was confirmed that the ratio of the minimum value T1m to the maximum value T2M was 46.6%. Furthermore, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 5.0%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 42.3 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 49.2%.

  In Comparative Example 1, as in Example 1, it was confirmed that the first mask element 41 had a substantially pentagonal shape in a cross section orthogonal to the second direction D2. Further, it was recognized that the first mask element 41 had a maximum value T1M, and the maximum value T1M was recognized to be 9.7 μm. As described above, since the first pitch P1 in which the plurality of mask holes are arranged along the first direction D1 is 195 μm, it is recognized that the ratio of the maximum value T1M to the first pitch P1 is 5.0%. It was.

  Further, in the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 165.9 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 5.8%.

[Comparative Example 2]
A metal mask base material made of Invar and having a thickness of 30 μm was prepared. Moreover, the metal mask for vapor deposition of the comparative example 2 was obtained by the same method as Example 1 except having changed the dimension of the 2nd resist pattern as follows. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 195 μm. there were.

  That is, in the second resist pattern, the pitch of the first pattern elements along the first direction is 195 μm, and the length of the first pattern elements along the first direction is 16.5 μm, along the second direction. The length of the first pattern element was 58.3 μm. In the second resist pattern, the length of the second pattern element along the second direction was 39.2 μm, and the length of the gap of the second pattern element was 14.4 μm. That is, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction is 12.4 μm.

  As shown in FIG. 14, in the vapor deposition metal mask 50 of Comparative Example 2, the thickness of the first mask element 51 has the minimum value T1m in the cross section orthogonal to the first direction D1, and the second mask element. It was found that the thickness of 52 had a maximum value T2M, the minimum value T1m was 10.4 μm, and the maximum value T2M was 12.7 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 81.9%. Furthermore, it was recognized that the ratio of the minimum value T1m to the second pitch P2 was 5.3%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 42.6 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 29.8%.

  In Comparative Example 2, as in Example 1, it was recognized that the first mask element 51 had a substantially pentagonal shape in a cross section orthogonal to the second direction D2. Further, it was recognized that the first mask element 51 had a maximum value T1M, and the maximum value T1M was recognized to be 10.4 μm. As described above, since the first pitch P1 in which the plurality of mask holes are arranged along the first direction D1 is 195 μm, it is recognized that the ratio of the maximum value T1M to the first pitch P1 is 5.3%. It was.

  In the cross section orthogonal to the second direction D2, the minimum value Wmm1 of the first mask hole width Wm1 is 165.6 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1 is 6. It was found to be 3%.

[Comparative Example 3]
A metal mask base material made of Invar and having a thickness of 25 μm was prepared. In addition, except that the dimensions of the first resist pattern and the dimensions of the second resist pattern were changed as follows, and the second resist pattern having a pattern element having no gap as the second pattern element was formed. A vapor deposition metal mask of Comparative Example 3 was obtained in the same manner as in Example 2. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 162. It was 5 μm.

  In the first resist pattern, the pitch of the first pattern elements along the first direction is 162.5 μm, the length of the first pattern elements along the first direction is 25 μm, and the first along the second direction. The length of the pattern element was 30.5 μm. In the first resist pattern, the length of the second pattern element along the second direction was 50.8 μm.

  In the second resist pattern, the pitch of the first pattern elements along the first direction is 162.5 μm, and the length of the first pattern elements along the first direction is 4.3 μm, along the second direction. The length of the first pattern element was 64.1 μm. In the second resist pattern, the length of the second pattern element along the second direction was 17.2 μm.

  As shown in FIG. 13, in the vapor deposition metal mask 40 of Comparative Example 3, the minimum value T1m in the thickness of the first mask element 41 is 8.0 μm in the cross section orthogonal to the first direction D1, and the second mask It was found that the maximum value T2M in the thickness of the element 42 was 17.4 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 46.0%. Further, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 4.9%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 35.1 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 49.6%.

  Furthermore, in the metal mask 40 for vapor deposition of the comparative example 3, it was recognized that the maximum value T1M in the thickness of the 1st mask element 41 is 8.0 micrometers in the cross section orthogonal to the 2nd direction D2. Since the first pitch P1 in which the plurality of mask holes 43 are arranged along the first direction D1 is 162.5 μm, it was confirmed that the ratio of the maximum value T1M to the first pitch P1 was 4.9%. .

  In the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 138.5 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 5.8%.

[Comparative Example 4]
A metal mask base material made of Invar and having a thickness of 25 μm was prepared. Moreover, the metal mask for vapor deposition of the comparative example 4 was obtained by the same method as Example 2 except having changed the dimension of the 2nd resist pattern as follows. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 162. It was 5 μm.

  That is, in the second resist pattern, the pitch of the first pattern elements along the first direction is 162.5 μm, the length of the first pattern elements along the first direction is 13.8 μm, and the second direction The length of the first pattern element along the line was 48.6 μm. In the second resist pattern, the length of the second pattern element along the second direction was 32.7 μm, and the length of the gap of the second pattern element was 12.0 μm. That is, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction was 10.3 μm.

  As shown in FIG. 14, in the metal mask for vapor deposition 50 of Comparative Example 4, the minimum value T1m in the thickness of the first mask element 51 is 8.3 μm in the cross section orthogonal to the first direction D1, and the second mask The maximum value T2M in the thickness of the element 52 was found to be 10.4 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 79.8%. Furthermore, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 5.1%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 35.2 μm, and the ratio of the maximum value T1M to the minimum value Wmm2 of the second mask hole width Wm2 was 29.5%.

  Furthermore, in the metal mask 50 for vapor deposition of the comparative example 4, it was recognized that the maximum value T1M in the thickness of the 1st mask element 51 is 8.3 micrometers in the cross section orthogonal to the 2nd direction D2. Since the first pitch P1 in which the plurality of mask holes 53 are arranged along the first direction D1 is 162.5 μm, it was recognized that the ratio of the maximum value T1M to the first pitch P1 was 5.1%.

  In the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 138.0 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 6.0%.

[Comparative Example 5]
A metal mask base material made of Invar and having a thickness of 20 μm was prepared. In addition, except that the dimensions of the first resist pattern and the dimensions of the second resist pattern were changed as follows, and the second resist pattern having a pattern element having no gap as the second pattern element was formed. A metal mask for vapor deposition of Comparative Example 5 was obtained in the same manner as Example 3. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 130 μm. there were.

  In the first resist pattern, the pitch of the first pattern elements along the first direction is 130 μm, the length of the first pattern elements along the first direction is 20 μm, and the first pattern elements along the second direction The length of was 24.4 μm. In the first resist pattern, the length of the second pattern element along the second direction was 40.6 μm.

  In the second resist pattern, the pitch of the first pattern elements along the first direction is 130 μm, the length of the first pattern elements along the first direction is 3.5 μm, and the first along the second direction. The length of the pattern element was 51.3 μm. In the second resist pattern, the length of the second pattern element along the second direction was 17.2 μm.

  As shown in FIG. 13, in the vapor deposition metal mask 40 of Comparative Example 5, the minimum value T1m in the thickness of the first mask element 41 is 7.0 μm in the cross section orthogonal to the first direction D1, and the second mask The maximum value T2M in the thickness of the element 42 was found to be 13.7 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 51.1%. Furthermore, the ratio of the minimum value T1m to the second pitch P2 was found to be 5.4%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 27.7 μm, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 was 49.5%.

  Furthermore, in the metal mask 40 for vapor deposition of Example 5, it was recognized that the maximum value T1M in the thickness of the 1st mask element 41 is 7.0 micrometers in the cross section orthogonal to the 2nd direction D2. Since the first pitch P1 in which the plurality of mask holes 43 are arranged along the first direction D1 is 130 μm, it was recognized that the ratio of the maximum value T1M to the first pitch P1 was 5.4%.

  In the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 110.6 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 6.3%.

[Comparative Example 6]
A metal mask base material made of Invar and having a thickness of 20 μm was prepared. Moreover, the metal mask for vapor deposition of the comparative example 6 was obtained by the same method as Example 3 except having changed the dimension of the 2nd resist pattern as follows. In a plan view facing the first surface, the first pitch P1 where the plurality of mask holes are positioned along the first direction and the second pitch P2 where the plurality of mask holes are positioned along the second direction are 130 μm. there were.

  That is, in the second resist pattern, the pitch of the first pattern elements along the first direction is 130 μm, and the length of the first pattern elements along the first direction is 11.0 μm, along the second direction. The length of the first pattern element was 38.9 μm. In the second resist pattern, the length of the second pattern element along the second direction was 26.1 μm, and the length of the gap included in the second pattern element was 9.6 μm. That is, in each of the two portions of the second pattern element that are located with a gap along the second direction, the length along the second direction was 8.3 μm.

  As shown in FIG. 14, in the metal mask for vapor deposition 50 of Comparative Example 6, the minimum value T1m in the thickness of the first mask element 51 is 7.3 μm in the cross section orthogonal to the first direction D1, and the second mask The maximum value T2M in the thickness of the element 52 was found to be 8.2 μm. That is, it was recognized that the ratio of the minimum value T1m to the maximum value T2M was 89.0%. Further, it was confirmed that the ratio of the minimum value T1m to the second pitch P2 was 5.6%.

  Further, it was confirmed that the minimum value Wmm2 of the second mask hole width Wm2 was 28.1 μm, and the ratio of the maximum value T1M to the minimum value Wmm2 of the second mask hole width Wm2 was 29.2%.

  Furthermore, in the vapor deposition metal mask 50 of Comparative Example 6, it was recognized that the maximum value T1M of the second mask element 52 was 7.3 μm in the cross section orthogonal to the second direction D2. Since the first pitch P1 in which the plurality of mask holes 53 are arranged along the first direction D1 is 130 μm, it was confirmed that the ratio of the maximum value T1M to the first pitch P1 was 5.6%.

  In the cross section orthogonal to the second direction D2, it is recognized that the minimum value Wmm1 of the first mask hole width Wm1 is 110.0 μm, and the ratio of the maximum value T1M to the minimum value Wmm1 of the first mask hole width Wm1. Was found to be 6.6%.

[Evaluation]
Immediately after each metal mask for vapor deposition was manufactured, it was evaluated whether or not the metal mask for vapor deposition occurred in the direction in which the first mask elements were connected. As described above, in each example and each comparative example, the maximum value T2M, the minimum value T1m, the ratio of the minimum value T1m to the maximum value T2M in the cross section in the direction orthogonal to the first direction D1, the second mask hole width Wm2 The ratio of the maximum value T2M to the minimum value Wmm2, the minimum value Wmm2 of the second mask hole width Wm2, and the ratio of the minimum value T1m to the second pitch P2 were values shown in Table 1 below. In each example and each comparative example, the maximum value T1M in the cross section orthogonal to the second direction D2, the ratio of the maximum value T1M to the first pitch P1, the minimum value Wmm1 of the first mask hole width Wm1, and the first The ratio of the maximum value T1M to the minimum value Wmm1 of the mask hole width Wm1 was a value shown in Table 1 below.

  In the metal mask 10 for vapor deposition of Example 1 to Example 3, it was recognized that the folding in the direction where the 1st mask element 21 continues was not produced. On the other hand, in the vapor deposition metal mask 40 of Comparative Example 1, the vapor deposition metal mask 40 of Comparative Example 3, and the vapor deposition metal mask 40 of Comparative Example 5, folding in the direction in which the first mask elements 41 are continuous is vapor deposition. It was observed that this occurred in almost the entire metal mask 40 for use. Further, in the vapor deposition metal mask 50 of Comparative Example 2, the vapor deposition metal mask 50 of Comparative Example 4, and the vapor deposition metal mask 50 of Comparative Example 6, the folding in the direction in which the first mask elements 51 are continuous is for vapor deposition. It was observed that this occurred in a part of the metal mask 50.

  Thus, in the metal mask for vapor deposition 10 of each example, the ratio of the minimum value T1m to the maximum value T2M is 70% or more, and the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 is It was confirmed that the bending of the first mask element 21 in the continuous direction can be suppressed if it is 41% or more.

  On the other hand, in the vapor deposition metal mask 40 of Comparative Example 1, the vapor deposition metal mask 40 of Comparative Example 3, and the vapor deposition metal mask 40 of Comparative Example 5, the maximum value of the second mask hole width Wm2 with respect to the minimum value Wmm2 is maximized. Although the ratio of the value T2M is 41% or more, the ratio of the minimum value T1m to the maximum value T2M is smaller than 70%. Therefore, in each metal mask for vapor deposition 40, the strength at the portion where the first mask element 41 is continuous is smaller than the strength of the other portions to the extent that the folds concentrate on the continuous portion of the first mask element 41, As a result, it is considered that the entire metal mask 40 for evaporation has been broken.

  Further, in the vapor deposition metal mask 50 of Comparative Example 2, the vapor deposition metal mask 50 of Comparative Example 4, and the vapor deposition metal mask 50 of Comparative Example 6, the ratio of the minimum value T1m to the maximum value T2M is 70% or more. However, although the variation in thickness in the cross section orthogonal to the first direction D1 is suppressed, the ratio of the maximum value T2M to the minimum value Wmm2 of the second mask hole width Wm2 is smaller than 41%. Therefore, in each metal mask 50 for vapor deposition, the strength at the portion where the first mask element 51 is continuous is such that the folding is concentrated at a part of the portion where the first mask element 51 is continuous as compared with the strength of the other portions. As a result, it is considered that the metal mask 50 for vapor deposition was broken.

As described above, according to one embodiment of the metal mask for vapor deposition, the effects listed below can be obtained.
(1) Since variations in thickness within the metal mask for vapor deposition 10 are suppressed, the first among the metal masks for vapor deposition 10 to such an extent that folding of the first mask elements 21 can be suppressed. The difference in strength between the continuous portion of the mask elements 21 and the other portions is suppressed. Therefore, it is possible to suppress the occurrence of continuous folds along the direction in which the mask holes 11 are arranged in the deposition metal mask 10.

  (2) Since the ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 is 41% or more, the strength of each first mask element 21 is the metal mask for vapor deposition. Compared with the other portions in FIG. 10, the size is such that the folding does not concentrate on the first mask element 21.

  (3) Even if the size of the first pitch P1 changes, that is, the size of the space included in the first pitch P1, the maximum value T1M in the thickness of the first mask element 21 is a predetermined size. Maintained above. Therefore, the generation | occurrence | production of the folding in the 1st mask element 21 is suppressed among the metal masks 10 for vapor deposition.

  (4) In the configuration in which the thickness of the first mask element 21 is ensured to be 12.5 μm or more, the metal mask 10 for vapor deposition has such a degree that the folding of the continuous portions of the first mask element 21 is suppressed. The difference in strength between the continuous portion of the first mask elements 21 and the other portions is further suppressed.

  (5) Since the ratio of the maximum value T1M in the thickness of the first mask element 21 to the minimum value Wmm1 of the first mask hole width Wm1 is 7% or more, the strength of each first mask element 21 is a metal mask for vapor deposition. Compared with other portions in FIG. 10, the size is such that the folding is not concentrated on the first mask element 21.

  (6) In the metal mask for vapor deposition 10 in which the plurality of mask holes 11 are arranged in a staggered arrangement, it is possible to suppress the continuous folding along the direction in which the mask holes 11 are arranged.

The embodiment described above can be implemented with appropriate modifications as follows.
As shown in FIG. 15, in the vapor deposition metal mask 60, the plurality of mask holes 61 are arranged at a constant pitch along the first direction D1 and the second direction D2 in a plan view facing the first surface 60a. And the position in the 1st direction D1 of the some mask hole 61 which comprises each row | line may be the same in all the row | line | columns. That is, the plurality of mask holes 61 may be arranged in a tetragonal lattice shape.

  Even in such a configuration, it is sufficient that the first width W1 of the first mask element 62 is smaller than the second width W2 of the second mask element 63. In the cross section perpendicular to the first direction D1, the ratio of the minimum value T1m in the thickness of the first mask element 62 to the maximum value T2M in the thickness of the second mask element 63 is 70% or more, and the first The ratio of the maximum value T2M in the thickness of the second mask element 63 to the minimum value Wmm2 of the second mask hole width Wm2 at the opening 11a may be 41% or more. According to such a metal mask 60 for vapor deposition, the same effects as (1) and (2) described above can be obtained.

  In the cross section orthogonal to the second direction D2, the ratio of the maximum value T1M in the thickness of the first mask element 21 to the minimum value Wmm1 of the first mask hole width Wm1 may be smaller than 7%. Even in such a configuration, in the cross section orthogonal to the first direction D1, the ratio of the minimum value T1m of the first mask element 21 to the maximum value T2M of the second mask element 22 is 70% or more, and the first opening The ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 at 11a may be 41% or more. Thereby, the effect equivalent to (1) and (2) mentioned above can be acquired.

  In the cross section orthogonal to the first direction D1, the ratio of the maximum value T2M in the thickness of the first mask element 21 in the cross section orthogonal to the second direction D2 with respect to the first pitch P1 may be smaller than 6%. Even in such a configuration, in the cross section orthogonal to the first direction D1, the ratio of the minimum value T1m of the first mask element 21 to the maximum value T2M of the second mask element 22 is 70% or more, and the first opening The ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 at 11a may be 41% or more. Thereby, the effect equivalent to (1) and (2) mentioned above can be acquired.

  In the cross section orthogonal to the first direction D1, the minimum value T1m in the thickness of the first mask element 21 may be smaller than 12.5 μm. Even in such a configuration, in the cross section orthogonal to the first direction D1, the ratio of the minimum value T1m of the first mask element 21 to the maximum value T2M of the second mask element 22 is 70% or more, and the first opening The ratio of the maximum value T2M in the thickness of the second mask element 22 to the minimum value Wmm2 of the second mask hole width Wm2 at 11a may be 41% or more. Thereby, the effect equivalent to (1) and (2) mentioned above can be acquired.

  The step of forming the second hole element 11d constituting the mask hole 11 uses the second resist pattern 35 to simultaneously form the first arc-shaped element dp1 and the second arc-shaped element dp2 connected by the inflection element dp3. You may comprise not only a process but the following processes. For example, in the step of forming the second hole element 11d, first, after a resist pattern for forming two second arc-shaped elements dp2 sandwiching one first arc-shaped element dp1 is positioned on the metal mask base material 31 The metal mask substrate 31 is etched using this resist pattern. Next, after the resist pattern used for etching is peeled off from the metal mask base material 31, the resist pattern for forming the first arc-shaped element dp1 is positioned on the metal mask base material 31, and the resist pattern is used to form metal. The mask substrate 31 is etched. Thereby, the 2nd hole element 11d can be formed. As described above, the second hole element 11d can be formed by repeating the formation of the resist pattern and the etching of the metal mask substrate 31 twice.

  The second hole element 11d constituting the mask hole 11 can be formed by repeating the formation of the resist pattern and the etching of the metal mask base material 31 three times or more. For example, each of one first arc-shaped element dp1 and two second arc-shaped elements dp2 constituting one second hole element 11d can be formed using different resist patterns. In this case, the second hole element 11d can be formed by repeating the formation of the resist pattern and the etching of the metal mask base material 31 three times.

  -The thickness of the base material 31 for metal masks may be thinner than 20 micrometers, for example, may be 10 micrometers or more and less than 20 micrometers. When such a metal mask base material 31 is used, a mask hole having a desired shape can be formed only by etching the metal mask base material 31 from the second surface 31b. The metal mask substrate 31 having a thickness of 10 μm or more and less than 20 μm is higher in definition than the metal mask 10 for vapor deposition that can be formed by the metal mask substrate 31 having a thickness of 20 μm or more. This is a preferable base material for manufacturing a metal mask 10 for vapor deposition.

  When such a metal mask base material 31 is used, the first resist layer 32 is formed on the first surface 31a of the metal mask base material 31 from the above-described method of manufacturing the vapor deposition metal mask 10, and the first Forming the first resist pattern 34 from the resist layer 32 can be omitted. In this case, the etching of the metal mask substrate 31 using the first resist pattern 34 can be omitted, thereby forming the second protective layer 36 and the first protection. Forming layer 37 can also be omitted.

  Thus, when the metal mask base material 31 having a thickness of 10 μm or more and less than 20 μm is used, the vapor deposition metal mask 10 can be obtained through the following steps. That is, vapor deposition is performed by forming a resist layer on the second surface 31b of the metal mask substrate 31, forming a resist pattern from the resist layer, and etching the metal mask substrate using the resist pattern. The metal mask 10 can be manufactured. In the middle of processing the metal mask base material 31 into the vapor deposition metal mask 10, a support member for supporting the metal mask base material 31 may be bonded to the metal mask base material 31.

  In the metal mask for vapor deposition 10 manufactured through these steps, the second mask hole width in the second opening is the largest and the second mask hole width in the first opening is the smallest in the cross section orthogonal to the first direction D1. The second mask hole width gradually decreases from the second opening toward the first opening. Therefore, the ratio of the maximum value T2M in the thickness of the second mask element 22 to the second mask hole width in the first opening may be 41% or more.

  -The metal mask for vapor deposition is not limited to the metal mask for vapor deposition used in the manufacture of organic EL displays, but the metal mask for vapor deposition used in the manufacture of other display devices, the formation of wiring provided in various devices, and various devices The metal mask for vapor deposition used for vapor deposition of the functional layer etc. which are equipped with may be sufficient.

  10, 40, 50, 60 ... metal mask for vapor deposition, 10a, 31a, 60a ... first surface, 10b, 31b ... second surface, 11, 43, 53, 61 ... mask hole, 11a ... first opening, 11b ... 2nd opening, 11c ... 1st hole element, 11cp ... 1st inner peripheral surface, 11d ... 2nd hole element, 11dp ... 2nd inner peripheral surface, 11e ... Continuous element, 21, 41, 51, 62 ... 1st mask Element, 22, 42, 52, 63 ... second mask element, 31 ... base material for metal mask, 32 ... first resist layer, 33 ... second resist layer, 34 ... first resist pattern, 34a, 35a ... first Pattern elements 34b, 35b ... second pattern element, 35 ... second resist pattern, 35c ... gap, 36 ... second protective layer, 37 ... first protective layer, cp1, dp1 ... first arc-shaped element, dp2 ... second Arcuate element, dp3 ... inflection element, 1 ... mask area, R2 ... peripheral area.

Claims (4)

A metal mask for vapor deposition comprising a plurality of mask holes arranged along a first direction and a second direction orthogonal to the first direction,
The metal mask for vapor deposition includes a first surface and a second surface,
Each mask hole has a first opening opened in the first surface, and a second opening opened in the second surface;
The element of the metal mask for vapor deposition that divides each mask hole,
Two first mask elements facing each other in the first direction, and two second mask elements facing each other in the second direction,
The first mask element and the mask hole are alternately repeated one by one along the first direction, and the second mask element and the mask hole are one along the second direction. Repeated alternately,
The width of the first mask element along the first direction is smaller than the width of the second mask element along the second direction;
In a cross section orthogonal to the first direction, a ratio of a minimum value in the thickness of the first mask element to a maximum value in the thickness of the second mask element is 70% or more;
In each mask hole, the width of the mask hole in a cross section orthogonal to the first direction is the mask hole width, and the mask hole width in the first opening is larger than the mask hole width in the second opening. Is also small,
The deposition metal mask, wherein a ratio of the maximum value in the thickness of the second mask element to the minimum value of the mask hole width between the first opening and the second opening is 41% or more. The plurality of mask holes are arranged at a constant pitch along the first direction,
The metal for vapor deposition according to claim 1, wherein a ratio of a maximum value to the pitch is 6% or more, and the maximum value is a maximum value in a thickness of the first mask element in a cross section orthogonal to the second direction. mask. In the mask hole, the mask hole width is a second mask hole width that is a mask hole width along the second direction, and the width of the mask hole in a cross section orthogonal to the second direction is along the first direction. A first mask hole width that is a mask hole width, wherein the first mask hole width in the first opening is smaller than the first mask hole width in the second opening;
The ratio of the maximum value in the thickness of the first mask element to the minimum value of the first mask hole width between the first opening and the second opening is 7% or more. Metal mask for vapor deposition. The metal mask for vapor deposition according to any one of claims 1 to 3, wherein the plurality of mask holes are arranged in a staggered arrangement as viewed from a direction orthogonal to a direction in which the metal mask for vapor deposition spreads.

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