Vapor deposition mask and method of manufacturing organic el element by using vapor deposition mask

Abstract

To provide a vapor deposition mask that can reduce film deposition of a vapor deposition material onto a scribe line that is a dicing position of a substrate.SOLUTION: One aspect of the present invention is a vapor deposition mask that includes an opening region including a first opening and a second opening, and a third opening arranged outside the opening region, wherein the first opening and the second opening are arranged along a first virtual line extending in a first direction, wherein the third opening is arranged between the first opening and a first end of the vapor deposition mask in the first direction, and wherein, in a second direction orthogonal to the first direction, a distance between the first opening and the first virtual line is shorter than a distance between the third opening and the first virtual line.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a deposition mask and a method for manufacturing an organic EL element using the deposition mask. [Background technology]

[0002] Organic EL elements (organic electroluminescent elements) have been attracting attention as light-emitting elements capable of emitting high-luminance light by low-voltage driving. Organic EL elements generally have a laminated structure in which a plurality of layers, such as an organic layer including an anode, a hole transport layer, a light-emitting layer, and an electron transport layer, and a cathode, are laminated on a substrate. Methods for forming this laminated structure include a vacuum deposition method on a substrate using evaporation or sublimation, and a film formation method using inkjet or spin coating in which an organic material is dissolved in a solvent.

[0003] When forming a layer using a low molecular weight material, a vacuum deposition method using a deposition mask having openings corresponding to a desired pattern is generally used. In the vacuum deposition method, in order to form a film of a desired pattern on a substrate, a deposition mask having pixel openings corresponding to the desired pattern is placed between the substrate and a heating unit for the deposition material, and then the film is formed.

[0004] By cutting the substrate on which the organic EL elements are formed, chips with multiple organic EL elements can be obtained from one substrate. For example, the blade dicing method, in which a circular blade is pressed against the substrate to perform cutting, is one method for cutting the organic EL elements from the substrate. Other methods include the laser ablation method, in which a laser beam is used to process the surface of the substrate, and the laser stealth dicing method, in which a laser beam is focused inside the substrate and an external force is applied to separate the chips.

[0005] The laser stealth dicing method causes less damage to the substrate surface and efficiently cuts out organic EL elements from a single substrate (obtaining as many organic EL elements as possible), making it possible to make the spacing between the organic EL elements placed on the substrate as narrow as possible.

[0006] In the blade dicing method and laser ablation method, the substrate is cut by scraping it with a blade, etc. Therefore, when the interval between the organic EL elements arranged on the substrate becomes narrow, it becomes difficult to secure the necessary margin for cutting when using the blade dicing method or laser ablation method.

[0007] On the other hand, the laser stealth dicing method is useful for cutting substrates to obtain organic EL elements because it does not damage the front and back surfaces of the substrate, is a dry process, and reduces the generation of processing waste.

[0008] Furthermore, the laser stealth dicing method requires a very narrow cutting margin, which reduces the scribe width required to cut the substrate. This makes it possible to narrow the distance between organic EL elements, making it a very effective substrate dicing method for efficiently obtaining organic EL elements from a single substrate.

[0009] In the process of cutting out organic EL elements from a single substrate, due to the shape and position of the substrate and the film formation region, an ineffective element region is generated in which the desired organic EL element size cannot be obtained. In this ineffective element region, it is not necessary to deposit a material on the substrate. Therefore, when evaporating the material for film formation, it is not necessary to provide an opening in the deposition mask at a position facing the ineffective element region of the substrate.

[0010] However, when an opening region with an opening and a region without an opening coexist in the same plane of the deposition mask facing the substrate, the rigidity in the deposition mask plane becomes biased, and the openings provided at the outermost periphery of the opening region become distorted, resulting in deposition blur. Deposition blur is a phenomenon in which the deposition material is deposited over a wide area on the substrate that exceeds the desired deposition area. This occurs when the deposition material gets into the gap that is created when the deposition mask and the substrate are placed opposite each other.

[0011] Patent Document 1 describes a method of providing a dummy opening on the outermost side of an effective opening in the tension direction of the deposition mask for each display element in a tension mask that applies tension to the deposition mask. Patent Document 1 also describes a method of providing dummy openings on the outer side of effective openings for multiple display elements in a single substrate, and a method of combining these. With this configuration, even if a tension force is applied to the deposition mask, it is the dummy openings that are largely distorted, and distortion of the effective openings can be suppressed. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] JP 2004-185832 A Summary of the Invention [Problem to be solved by the invention]

[0013] However, in the laser stealth dicing method, if material adheres to the surface of the substrate, it becomes difficult to focus the laser inside the substrate, and there is a possibility that some parts cannot be diced. Therefore, the present disclosure provides a deposition mask that can reduce deposition of deposition material on the scribe lines, which are the dicing positions of the substrate. [Means for solving the problem]

[0014] One aspect of the present disclosure relates to a deposition mask having an opening region having a first opening and a second opening, and a third opening arranged outside the opening region, wherein the first opening and the second opening are arranged along a first imaginary line extending in a first direction, the third opening is arranged between the first opening and an end of the deposition mask in the first direction, and a distance between the first opening and the first imaginary line in a second direction perpendicular to the first direction is shorter than a distance between the third opening and the first imaginary line.

[0015] Also, another embodiment of the present disclosure is a liquid crystal display device including an opening region having a first opening having a first side parallel to a first direction and a second side parallel to a second direction perpendicular to the first direction, and a second opening arranged alongside the first opening in the first direction; and a third opening arranged in the first direction relative to the first opening, the third opening being arranged between the opening region and an end of the deposition mask, and wherein, when a line adjacent to the first opening and extending in the first direction is defined as a first virtual line, a distance between the first opening and the first virtual line in the second direction is shorter than a distance between the third opening and the first virtual line. Effect of the Invention

[0016] With the above configuration, it is possible to provide a deposition mask in which deposition of the deposition material onto scribe lines, which are dicing positions of the substrate, is reduced. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram for explaining an example of a deposition mask 1 according to an embodiment. [Diagram 2] FIG. 1 is an enlarged view for explaining an example of a deposition mask 1 according to an embodiment. [Diagram 3] FIG. 1 is an enlarged view for explaining an example of a deposition mask 1 according to an embodiment. [Figure 4] FIG. 4A is a schematic diagram illustrating an example of a deposition mask 1 according to an embodiment; FIG. 4B and FIG. 4C are enlarged views of a portion of the deposition mask 1 in FIG. [Diagram 5] 5A is a schematic diagram illustrating an example of a deposition mask 1 according to an embodiment, and FIGS. 5B and 5C are enlarged views of a portion of the deposition mask 1 in FIG. 5A. [Figure 6] FIG. 1 is an enlarged view for explaining an example of a deposition mask 1 according to an embodiment. [Figure 7] FIG. 1 is an enlarged view for explaining an example of a deposition mask 1 according to an embodiment. [Figure 8]8(a) and (b) are schematic diagrams for explaining an example of a deposition mask 1 according to an embodiment; (c) and (e) are enlarged views of an example of a portion of the deposition mask 1 in FIG. 8(a); (d) and (f) are enlarged views of an example of a portion of the deposition mask 1 in FIG. 8(b). [Figure 9] 8(a), (c), and (e) are enlarged views of an example of a portion of the deposition mask 1 in FIG. 8(a), and (b), (d), and (f) are enlarged views of an example of a portion of the deposition mask 1 in FIG. 8(b). [Figure 10] FIG. 1 is a schematic diagram for explaining a vapor deposition process according to an embodiment; [Figure 11] Schematic diagram to explain the positional relationship of the substrate, deposition mask, and deposition source (crucible) in the deposition chamber. [Figure 12] Schematic diagram for explaining deposition masks of Comparative Examples 1 to 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the accompanying drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0019] In this embodiment, as an example of a deposition mask, a deposition mask used for forming a desired pattern on a substrate by a vacuum deposition method will be described with reference to FIGS.

[0020] The deposition mask 1 of the present embodiment can be formed by, for example, wet etching. The material can be, for example, any one of stainless steel, iron, copper, aluminum, silver, titanium, molybdenum, tungsten, invar, silicon, and resin, or a combination of these, but is not limited to these materials.

[0021] Fig. 1 shows a schematic diagram of an example of a deposition mask 1 in this embodiment. Fig. 1(a) and Fig. 1(b) show an example of a deposition mask having a circular outer shape, and Fig. 1(c) shows an example of a deposition mask 1 having a rectangular outer shape. The deposition mask 1 has an opening region W having a plurality of effective openings 2. In the opening region W, the openings 2 which are effective openings are arranged at positions corresponding to organic EL elements formed on a substrate by deposition.

[0022] The organic EL elements formed on the substrate are cut out by, for example, dicing using a laser stealth dicing method, and each is made into an individual organic EL element chip. In this specification, the cutting line of the substrate cut during dicing is called a scribe line. In addition, in the deposition mask 1, when the deposition mask and the substrate face each other during deposition, a line facing the scribe line, i.e., a line obtained by projecting the scribe line perpendicularly onto the deposition mask, is called a virtual line.

[0023] 1(a), the opening region W has a first opening 2a and a second opening 2b which are effective openings. The first opening 2a and the second opening 2b are arranged along a virtual line 4 (first virtual line) extending in a first direction X. A dummy opening 3 (third opening) is arranged outside the opening region W. The dummy opening 3 may be arranged, for example, outside (on the outer periphery side) of all the openings 2 arranged in the deposition mask 1, that is, at a position close to an edge of the deposition mask 1.

[0024] When an opening is provided in the deposition mask 1, a bias in rigidity occurs within the deposition mask plane due to the difference in structure between the opening region W and the region outside of it (presence or absence of an opening). By providing a dummy opening 3 between the opening region W and the end of the deposition mask 1, this bias in rigidity can be alleviated. For example, by providing a third opening between the first opening 2a and the end of the deposition mask 1 in the first direction X, it is possible to disperse the force that distorts the first opening 2a in the first direction and maintain the normal shape of the first opening 2a (or maintain a state close to the normal shape).

[0025] Since deformation of the effective aperture can be suppressed, deposition blurring during deposition of the laminated film of the organic EL element formed on the substrate can be mitigated, thereby improving yields in the manufacturing process of organic EL elements and reducing the costs of organic EL elements.

[0026] The deposition mask 1 shown in Fig. 1(b) is obtained by changing some of the openings 2 arranged in the opening region W of Fig. 1(a) to dummy openings 3. The deposition mask 1 shown in Fig. 1(c) has a rectangular outer shape, but is similar to Figs. 1(a) and 1(b) in terms of the opening region W having a plurality of openings 2 as effective openings, the dummy openings 3 arranged between the opening region W and the edge of the deposition mask, the virtual line 4, and the like.

[0027] 2(a) to 2(e) and 3(a) to 3(f) are schematic diagrams for explaining an example of a relationship between a part of the openings 2 and a part of the dummy openings 3 arranged in the opening region W. For example, as shown in Fig. 2(a), in the deposition mask of the present embodiment, a dummy opening 3 is arranged between a first opening 2a and an end of the deposition mask 1 (on the right side in the figure, not shown) in the first direction.

[0028] In a second direction Y perpendicular to the first direction X, the distance between the first opening 2a and the first virtual line 4a adjacent to the first opening 2a is distance L, and the distance between the third opening (dummy opening 3) and the first virtual line 4a is distance D. In the second direction Y, the distance L between the first opening 2a and the first virtual line 4a is shorter than the distance D between the third opening and the first virtual line 4a. That is, the third opening is farther from the first virtual line 4a than the first opening 2a.

[0029] In the deposition mask 1, the distance L in the second direction Y between the opening 2, which is an effective opening, and the virtual line 4 is set to a distance equal to or greater than the distance at which the deposition material does not deposit on the scribe line even if deposition blurring occurs that is expected in advance in the deposition process. The distance L between the first opening 2a and the first virtual line 4 is shorter than the distance D between the third opening (dummy opening 3) and the first virtual line 4, which means that the dummy opening 3 is farther from the first virtual line 4 than the opening 2, which is an effective opening. In other words, the third opening is disposed farther away from the virtual line 4 in the second direction Y than the distance at which the deposition material does not deposit on the scribe line during deposition.

[0030] By adopting such a configuration, even if the shape of the dummy opening 3 becomes distorted and the deposition blur becomes larger than what was previously assumed for the effective opening, it is possible to prevent the deposition material from adhering (forming a film) to the scribe line.

[0031] In this specification, when an object A has an area, the distance from the object A to a line refers to the shortest distance from the object A to the line. The distance in a certain direction refers to the shortest distance between the object A and the line in a certain direction.

[0032] As the deposition method using the deposition mask of this embodiment, a rotational deposition method using a point source, a deposition method using a linear source to move a crucible and a substrate relatively, etc. can be used. For example, in the case of rotational deposition, deposition blurring is more likely to occur from the center of the substrate to the outside. This is because, when comparing the center and the outer periphery of the deposition mask, even if the openings are arranged with the same shape and the same period, the incidence angle of the deposition component from the deposition source to the opening is gentler in the outer periphery, so deposition blurring is more likely to occur.

[0033] In addition, in the film formation method using a linear source, a shielding plate is generally used to reduce deposition blur in order to control the film formation. However, it is difficult to provide a shielding plate in all directions, and it is not possible to completely prevent the deposition components from being deposited up to the scribe line in some directions.

[0034] Therefore, with the configuration of this embodiment, in the process of forming a film from a deposition material by a vacuum deposition method, it is possible to prevent the deposition material from adhering (forming a film) onto the scribe line due to deposition blur.

[0035] When there are multiple virtual lines 4 adjacent to the first opening 2a, it is preferable that the shortest distance among the distances L between the first opening 2a and the multiple virtual lines 4 in the second direction Y is shorter than the distance D between the third opening (dummy opening 3) and the virtual line 4 in the second direction Y. For example, in FIG. 2(a), a line adjacent to the first opening 2a on the opposite side of the first virtual line 4a of the first opening 2a and parallel to the first virtual line 4a is defined as a second virtual line 4b. In this case, it is preferable that the shorter distance among the distance between the first opening 2a and the first virtual line 4a and the distance between the first opening 2a and the second virtual line 4b in the second direction Y is shorter than the distance between the third opening and the second virtual line 4b.

[0036] With this configuration, it is possible to prevent the deposition film from being formed on the scribe line on the substrate during deposition.

[0037] Therefore, the deposition mask of the present embodiment can reduce deposition blur caused by distortion of the deposition mask and suppress deposition on the scribe line in the deposition process, which makes it possible to cut out the organic EL elements from the substrate by, for example, a laser stealth dicing method, thereby improving the yield in the manufacturing process of the organic EL elements and reducing the cost of the organic EL elements.

[0038] In Fig. 2(a), an example is described in which the first opening 2a is a rectangle having a first side parallel to the first direction X and a second side parallel to the second direction Y perpendicular to the first direction, but the shape of each opening is not limited to this. In addition, the openings do not have to have the same shape or size. Other examples of the openings 2 and the dummy openings 3 will be described with reference to Figs. 2(b) to 2(e) and Figs. 3(a) to 3(f).

[0039] 2(b) and 2(c) show examples in which the size of the dummy opening 3 is different from that in FIG. 2(a). Also, FIG. 2(d) shows an example in which the opening 2 and the dummy opening 3 have long sides parallel to the second direction Y and short sides parallel to the first direction X. Even in such a case, the shortest distance between the first opening 2a and the virtual line 4 in the second direction Y is shorter than the distance between the dummy opening 3 and the virtual line 4 (any distance). Therefore, deposition blurring in the opening 2 can be suppressed, while deposition material can be prevented from adhering to the scribe line during deposition.

[0040] 2(e) shows an example in which a plurality of openings 2 and dummy openings 3 are arranged in a region between two adjacent virtual lines 4. Even in such a case, as described above, it is preferable that the shortest distance between the openings 2 and the virtual lines 4 in the second direction Y is shorter than the distance between the dummy openings 3 and the virtual lines 4 (any distance).

[0041] That is, the shorter of the distance between the dummy opening 3 and the first virtual line 4a and the distance between the dummy opening 3 and the second virtual line 4b is preferably longer than the shortest distance between the multiple openings 2 and the first virtual line 4a. Also, the shorter of the distance between the dummy opening 3 and the first virtual line 4a and the distance between the dummy opening 3 and the second virtual line 4b is preferably longer than the shortest distance between the multiple openings 2 and the second virtual line 4b.

[0042] 3(a) to 3(f) show an example in which a plurality of dummy openings 3 are arranged in a region sandwiched between two virtual lines 4. In Fig. 3(a) and Fig. 3(b), two dummy openings 3 having a shape similar to that of the opening 2 are arranged in the first direction X with respect to the opening 2 in a region sandwiched between two adjacent virtual lines 4. Even in this case, it is preferable that the distance between each of the dummy openings 3 and the virtual lines 4 in the second direction Y is longer than the shortest distance between the opening 2 and the virtual wiring 4. With such a configuration, it is possible to suppress the deposition of the deposition material on the scribe line while suppressing distortion of the opening 2.

[0043] 3(c) to 3(f) show an example in which a plurality of openings 2 and a plurality of dummy openings 3 are provided in a region sandwiched between two adjacent imaginary lines 4. In Fig. 3(c), the plurality of openings 2 are polygonal, and two dummy openings 3 are provided between an opening region W and an end of the deposition mask (not shown, on the right side in the figure). Also, within the opening region W, dummy openings 3 smaller in size than the dummy openings 3 provided outside the opening region W are provided.

[0044] 3(d), the multiple openings 2 are rectangular, and one dummy opening 3 is arranged between the opening region W and an end of the deposition mask (not shown, right side in the figure). Also, within the opening region W, a dummy opening 3 smaller in size than the dummy openings 3 arranged outside the opening region W is arranged.

[0045] 3(e), the multiple openings 2 have rectangular openings of different sizes, and one dummy opening 3 is arranged between the opening region W and an end of the deposition mask (not shown, right side in the figure). Also, within the opening region W, a dummy opening 3 having a size different from the dummy openings 3 arranged outside the opening region W is arranged.

[0046] 3(f), two rectangular openings 2 are arranged, and a dummy opening 3 is arranged between the opening 2 and an end of the deposition mask (not shown, right side in the figure) alongside the opening 2 in the first direction X. In addition, two elliptical dummy openings 3 and one rectangular dummy opening 3 are arranged at positions overlapping with the opening 2 in the second direction Y.

[0047] 3(c) to 3(f), it is also preferable that the distance between any of the dummy openings 3 and the virtual lines 4 in the second direction Y is longer than the shortest distance between the openings 2 and the virtual wiring 4. With such a configuration, it is possible to suppress the deposition of the deposition material on the scribe line while suppressing distortion of the openings 2.

[0048] 2(a) to 2(e) and 3(a) to 3(f), it is desirable that the opening 2 and the third opening 3 adjacent to each other in the first direction X overlap in the first direction X. When the member A overlaps with the member B in a certain direction, it means that when the members A and B are projected onto a plane perpendicular to a certain direction, the projections have portions that overlap each other. Note that, when multiple third openings 3 are arranged in an area sandwiched between two adjacent virtual lines, it is sufficient that any one of these has an overlap with the adjacent opening 2 in the first direction, and it is not necessary that all of the multiple third openings 3 have an overlap with the opening 2.

[0049] The openings 2 and the dummy openings 3 are not particularly limited as long as they penetrate the deposition mask from the surface facing the substrate toward the back surface of the deposition mask. They may be openings perpendicular to the plane of the deposition mask, and the openings on the deposition mask facing surface and the openings on the back surface of the deposition mask may have the same shape or different shapes. The openings may also have the same size or different sizes. When the shapes and sizes of the openings 2 and the dummy openings 3 are different between the substrate facing surface side and the back surface side of the deposition mask, the shapes in this specification refer to the shapes and sizes on the surface of the deposition mask facing the substrate.

[0050] The opening 2 is an effective opening for forming an organic EL element, and the third opening 3 is a dummy opening that is not used for forming an organic EL element.

[0051] As described above, when there are a plurality of virtual lines 4, a single opening 2 or a plurality of openings 2 may be arranged in the region between adjacent virtual lines 4, but it is preferable that at least one opening 2 is arranged. As shown in Fig. 3(c) to Fig. 3(f), a dummy opening 3 may be arranged between the openings 2 in the first direction X and the second direction Y, or a dummy opening 2 may be arranged between the dummy openings 3. Alternatively, the openings 2 may be adjacent to each other.

[0052] When attaching a deposition mask to a frame that supports the deposition mask, a force may be applied in a direction that distorts the opening in order to maintain a certain flatness, whether it is a tension mask that is stretched by applying a tensile force or a deposition mask that is simply fixed with pins, screws, etc. Therefore, by arranging dummy openings 3 not only around the frame but also between the pins, screws, etc. and the effective opening, the force can be alleviated and the desired pattern shape can be deposited.

[0053] Furthermore, when the dummy opening 3 is provided for a completely different purpose, for example, it may be provided as an inspection area for checking the soundness of the manufacturing process. In the present disclosure, the dummy opening 3 is an opening for forming a vapor deposition film that has no function for element formation, and the purpose such as the use of the formed film is not particularly limited.

[0054] In this embodiment, the openings 2 and the dummy openings 3 are exemplified as being rectangular, polygonal, and elliptical, but there is no particular limitation on the shapes of the openings 2 and the dummy openings 3. For example, the openings 2 and the dummy openings 3 may be polygonal, such as a triangle, a square, a pentagon, or a dodecagon, or may be a shape without corners, such as a circle or an ellipse, or may even be a semicircle or other shape.

[0055] 1 shows an example of a square and a circle as the shape of the deposition mask 1, but the shape of the deposition mask 1 is not limited thereto. For example, the shape of the deposition mask 1 may be a circle or a polygon, and may have a notch or a protrusion that matches a deposition mask transport mechanism or a deposition mask frame of a deposition device.

[0056] Fig. 4(a) is a schematic diagram of an example of the structure seen from the deposition mask side when the deposition mask 1 of the present embodiment is opposed to a square substrate, Fig. 4(b) and Fig. 4(c) are enlarged views of the thick line inside Fig. 4(a). Fig. 5(a) is a schematic diagram of an example of the structure seen from the deposition mask side when the deposition mask 1 of the present embodiment is opposed to a circular substrate, and Fig. 5(b) and Fig. 5(c) are enlarged views of the thick line inside Fig. 5(a).

[0057] As shown in the enlarged view, the dummy openings 3 provided outside the opening region W may have a shape that follows the edge of the substrate 11 facing the deposition mask 1 of this embodiment, or may have a different shape. For example, as shown in Figures 4(b) and 5(b), the dummy openings 3 may have a shape that protrudes from the edge of the substrate 11, and as shown in Figures 4(c) and 5(c), the dummy openings 3 may have a shape that has an edge that matches the edge of the substrate 11.

[0058] As shown in Figures 4(c) and 5(c), the dummy openings 3 have a shape that follows the edge of the substrate 11, which is preferable because it can reduce deposition of unnecessary deposition material on a deposition mask frame on which the deposition mask 1 is placed and on other parts in the deposition chamber.

[0059] The arrangement of the openings 2 will be described with reference to Figures 6 and 7. In Figure 6(a), a plurality of openings 2 are arranged between two adjacent virtual lines 4, namely, virtual line 4a and virtual line 4b. In Figures 6(b) and 6(c), one opening 2 is arranged between two adjacent virtual lines 4. In Figure 6(b), the width of the dummy opening 3 in the second direction Y is smaller than that of the dummy opening 3 in Figure 6(a). In Figure 6(c), the openings 2 and dummy openings 3 have a shape in which the long sides are parallel to the second direction Y and the short sides are parallel to the first direction X, and the dummy openings are trapezoidal.

[0060] 6(a) to 6(e) each have a virtual line 4 extending in a second direction Y perpendicular to the first direction X. For example, the deposition mask 1 shown in FIG. 6(a) has a third virtual line 4c and a fourth virtual line 4d which are two adjacent virtual lines 4 extending in the second direction Y. The deposition masks 1 shown in FIG. 6(b) to 6(e) also have a third virtual line 4c and a fourth virtual line 4d which are two adjacent virtual lines 4 extending in the second direction Y.

[0061] In the deposition mask 1 in FIGS. 7(a) and 7(b), the third virtual line 4c and the fourth virtual line 4d are parallel to each other and intersect the first direction, but are not perpendicular to the first direction.

[0062] The openings arranged in the area E surrounded by the first virtual line 4a, the second virtual line 4b, the third virtual line 4c, and the fourth virtual line 4d may be multiple or may be single, but it is preferable that at least one opening 2 is arranged.

[0063] 6(a) to 6(e) and 7(a) and 7(b), the shortest distance between the opening 2 and the virtual line 4 in the second direction Y is shorter than the distance (any distance) between the dummy opening 3 and the virtual line 4. In this case, the shortest distance between the opening 2 and the virtual line 4 extending in the second direction Y in the first direction X is shorter than the distance (any distance) between the dummy opening 3 and the virtual line 4 extending in the second direction Y.

[0064] Therefore, it is possible to suppress the distortion of the opening 2 and also to suppress deposition of the deposition material on the scribe line.

[0065] FIG. 8 is a schematic diagram showing an example of a configuration seen from the deposition mask side when a deposition mask 1 having virtual lines 4 (virtual lines 4a and 4b) extending in a first direction X and virtual lines 4 (virtual lines 4c and 4d) extending in a second direction Y is placed opposite a rectangular substrate or a circular substrate.

[0066] Fig. 8(a) is a schematic diagram of an example of the deposition mask 1 of the present embodiment facing a rectangular substrate as viewed from the deposition mask side, Fig. 8(c), Fig. 8(e), Fig. 9(a), Fig. 9(c), and Fig. 9(e) are enlarged views of the thick line inside Fig. 8(a). Fig. 8(b) is a schematic diagram of an example of the configuration of the deposition mask 1 of the present embodiment facing a circular substrate as viewed from the deposition mask side, and Fig. 8(d), Fig. 8(f), Fig. 9(b), Fig. 9(e), and Fig. 9(f) are enlarged views of the thick line inside Fig. 8(b).

[0067] As shown in the enlarged view, the dummy openings 3 provided outside the opening region W may have a shape that follows the edge of the substrate 11 facing the deposition mask 1 of this embodiment, or may have a different shape. For example, as shown in Figures 8(c) to 9(b), the dummy openings 3 may have a shape that protrudes from the edge of the substrate 11, and as shown in Figures 9(c) to 9(f), the dummy openings 3 may have a shape that has an opening edge aligned with the edge of the substrate 11.

[0068] As shown in Figures 9(c) to 9(f), the dummy openings 3 have a shape that follows the edge of the substrate 11, which is preferable because it can reduce deposition of unnecessary deposition material on a deposition mask frame on which the deposition mask 1 is placed and on other parts in the deposition chamber.

[0069] The opening region W of this embodiment has a plurality of openings. For example, in FIG. 9(d), the opening region W has a first opening 2a and a second opening 2b arranged along a virtual line 4 (first virtual line) extending in the first direction X. The opening region W also has a fourth opening 2c arranged adjacent to the first opening 2a across the first virtual line, and a fifth opening 2d arranged alongside the fourth opening 2c in the first direction X. The fifth opening 2d is adjacent to the second opening 2b across the first virtual line. A dummy opening 3 (third opening) is arranged outside the opening region W. Even in this configuration, the distance between the dummy opening 3 and the virtual line 4 adjacent to the dummy opening 3 is longer than the shortest distance between the opening 2 and the virtual wiring 4. Therefore, it is possible to suppress the deposition of the deposition material on the scribe line while suppressing the distortion of the opening 2.

[0070] An organic EL element that can be produced using the deposition mask 1 of this embodiment is an element including at least one organic compound layer between a first electrode and a second electrode. One of the first electrode and the second electrode is an anode and the other is a cathode. In the organic EL element of this embodiment, the organic compound layer may be a single layer or a laminate consisting of multiple layers, so long as it has a light-emitting layer.

[0071] When the organic compound layer is a laminate consisting of multiple layers, the organic compound layer may have, in addition to the light-emitting layer, a hole injection layer, a hole transport layer, an electron blocking layer, a hole-exciton blocking layer, an electron transport layer, an electron injection layer, etc. The light-emitting layer may be a single layer or a laminate consisting of multiple layers.

[0072] In the case where the light-emitting layer is a multi-layer structure, a charge-generating layer may be provided between the light-emitting layers. The charge-generating layer may be composed of a compound having a lower LUMO than the hole-transporting layer, and the LUMO of the charge-generating layer may be lower than the HOMO of the hole-transporting layer. Here, the molecular orbital energy of the organic compound layer may be the molecular orbital energy of the organic compound having the largest weight ratio in the organic compound layer.

[0073] Here, the closer the HOMO and LUMO are to the vacuum level, the higher they are described as being. The LUMO of the charge generating layer being lower than the HOMO of the hole transporting layer means that the LUMO of the charge generating layer is closer to the vacuum level than the HOMO of the hole transporting layer.

[0074] Next, a vacuum deposition process using the deposition mask of the present embodiment will be described with reference to FIG. 10, but the present disclosure is not limited thereto. In a deposition chamber, for example, a desired deposition pattern can be formed on a substrate 11 by the following configuration. A method for manufacturing an organic EL element includes a step of opposing the deposition mask of the present embodiment to the substrate 11, a step of aligning the substrate 11 and the deposition mask, and a step of forming a desired pattern on the substrate by depositing a deposition material through the openings of the deposition mask 1. Here, in the step of aligning the substrate 11 or the deposition mask 1, the scribe line provided on the substrate 11 and the virtual line 4 of the deposition mask 1 are positioned to face each other.

[0075] First, as shown in FIG. 10(a), the substrate 11 held by the substrate holding arm 120 and the deposition mask 1 arranged on the mask stage 200 are made to face each other. Next, as shown in FIG. 10(b), for example, the substrate 11 and the deposition mask 1 are aligned by moving one or both of them. The imaginary line 4 is a collection of positions on the deposition mask 1 that face the scribe lines provided on the substrate 11 at this time. Next, as shown in FIG. 10(c), a deposition material 300 is deposited on the substrate 11 through openings 2 (not shown) of the deposition mask 1, thereby forming a desired pattern on the substrate 11.

[0076] In the deposition mask 1, the distance L in the second direction Y between the opening 2, which is an effective opening, and the virtual line 4 is set to a distance equal to or greater than the distance at which the deposition material does not deposit on the scribe line even if deposition blurring occurs that is expected in advance in the deposition process. Also, the distance D in the second direction Y between the dummy opening 3 (third opening) and the virtual line 4 is longer than the shortest distance L among the distances L in the second direction Y between the opening 2 and the virtual line 4. Thus, the third opening is disposed farther away from the virtual line 4 in the second direction Y than the distance at which the deposition material does not deposit on the scribe line during deposition.

[0077] In the deposition process, the shape of the dummy openings 3 arranged outside the opening region W may be distorted, and the deposition blur of the deposition material deposited through the dummy openings 3 may be larger than that previously expected for the openings 2, which are effective openings. However, by depositing using the deposition mask 1 of the present embodiment, even if the shape of the dummy openings 3 is distorted, it is possible to prevent the deposition material deposited through the dummy openings 3 from adhering (forming a film) to the scribe line.

[0078] Here, an example of an apparatus for manufacturing an organic EL element will be described, but the present disclosure is not limited thereto. An organic EL element has a plurality of functional layers, and a vapor deposition apparatus, which is an apparatus for manufacturing the organic EL element, is composed of a number of vapor deposition chambers corresponding to the plurality of functional layers. In addition to the vapor deposition chambers, the apparatus may also be equipped with a plurality of process chambers such as a loading chamber, a pretreatment chamber, a transfer chamber, a relay chamber, and a substrate stock chamber.

[0079] FIG. 11(a) is a schematic diagram of a deposition chamber in which a substrate and a deposition mask are placed directly above the deposition source, and it is assumed that one layer is to be deposited. On the other hand, FIG. 11(b) is a schematic diagram of a deposition chamber in which it is assumed that multiple layers are to be deposited continuously in one deposition chamber, and only one crucible 15 is shown in the figure for the sake of explanation, but multiple crucibles may be placed. Compared to FIG. 11(a), the deposition chamber shown in FIG. 11(b) has a large deposition blur 18 shown in the enlarged view of the area surrounded by the thick line. This is because the incidence angle between the dotted line 16 from the deposition source to the opening at the outermost periphery and the substrate 11 is smaller in FIG. 11(b) than in FIG. 11(a). The width of this deposition blur 18 is determined by the following distance relationship. A. The distance between the substrate 11 and the deposition mask 1, B. TS distance 19, which is the perpendicular distance from the deposition source to the substrate plane; C. OFFSET20 is the distance between the center of the crucible opening and the point where the perpendicular line drawn from the center of the substrate to the crucible opening plane intersects with the crucible opening plane.

[0080] [When A is constant and B is constant] 11(b), the shorter the crucible 15 moves in the horizontal direction, that is, the shorter C becomes, the larger the angle of incidence between the dotted line 16 from the deposition source to the outermost opening and the substrate, and the smaller the width of deposition blur 18 becomes. Therefore, when A and B are constant, it is preferable to have a shorter C, since this suppresses deposition blur and reduces deposition on the scribe line.

[0081] [When A and C are constant] 11(b), the longer crucible 15 moves in the vertical direction, that is, the longer B becomes, the larger the angle of incidence between dotted line 16 from the deposition source to the outermost opening and substrate 11 becomes, and the smaller the width of deposition blur 18 becomes. Therefore, when A and C are constant, it is preferable that B is longer, since this suppresses deposition blur and reduces deposition on scribe lines.

[0082] [When B and C are constant] 11(b), the shorter A is, the larger the angle of incidence between the dotted line 16 from the deposition source to the outermost opening and the substrate, and the smaller the width of deposition blur 18. Therefore, when B and C are constant, a shorter A is preferable because it suppresses deposition blur and reduces deposition on the scribe line.

[0083] When two or more of A, B, and C fluctuate, the width of the deposition blur 18 becomes larger or smaller depending on the width of the fluctuation.

[0084] The present disclosure includes, for example, the following configurations.

[0085] (Configuration 1) 1. A deposition mask having an opening region having a first opening and a second opening, and a third opening arranged outside the opening region, wherein the first opening and the second opening are arranged along a first virtual line extending in a first direction, the third opening is arranged between the first opening and an end of the deposition mask in the first direction, and a distance between the first opening and the first virtual line in a second direction perpendicular to the first direction is shorter than a distance between the third opening and the first virtual line.

[0086] (Configuration 2) 1. A deposition mask comprising: an opening region having a first opening having a first side parallel to a first direction and a second side parallel to a second direction perpendicular to the first direction, and a second opening arranged side by side with the first opening in the first direction; and a third opening arranged in the first direction relative to the first opening, wherein the third opening is arranged between the opening region and an end of the deposition mask, and wherein, when a line adjacent to the first opening and extending in the first direction is defined as a first virtual line, a distance between the first opening and the first virtual line in the second direction is shorter than a distance between the third opening and the first virtual line.

[0087] (Configuration 3) In the deposition mask according to configuration 1 or 2, the opening region has a fourth opening, and the fourth opening is disposed adjacent to the first opening across the first virtual line.

[0088] (Configuration 4) In configuration 3, the deposition mask is arranged at a position overlapping with the first opening in the second direction.

[0089] (Configuration 5) In the deposition mask of configuration 3 or 4, the opening region has a fifth opening arranged alongside the fourth opening in the first direction, and the fifth opening is adjacent to the second opening across the first virtual line.

[0090] (Configuration 6) In any one of configurations 1 to 5, when a line adjacent to the first opening on the opposite side of the first virtual line from the first opening and parallel to the first virtual line is defined as a second virtual line, the third opening is located between the first virtual line and the second virtual line.

[0091] (Configuration 7) In any one of configurations 1 to 6, when a line adjacent to the first opening on the opposite side of the first virtual line from the first opening and parallel to the first virtual line is defined as a second virtual line, in the second direction, the shorter of the distance between the first opening and the first virtual line and the distance between the first opening and the second virtual line is shorter than the distance between the third opening and the second virtual line.

[0092] (Configuration 8) In configuration 7, the deposition mask wherein the second opening is between the first virtual line and the second virtual line.

[0093] (Configuration 9) In any one of configurations 1 to 6, when a line adjacent to the first opening on the side opposite the first virtual line from the first opening and parallel to the first virtual line is defined as a second virtual line, the opening region has a plurality of openings between the first virtual line and the second virtual line, and in the second direction, the shorter of a distance between the third opening and the first virtual line and a distance between the third opening and the second virtual line is longer than the shortest distance between the plurality of openings and the first virtual line and is longer than the shortest distance between the plurality of openings and the second virtual line.

[0094] (Configuration 10) 10. The deposition mask according to any one of configurations 1 to 9, wherein the first opening and the second opening are effective openings, and the third opening is a dummy opening.

[0095] (Configuration 11) In any one of configurations 1 to 10, in a dicing step of cutting a substrate on which a substance has been deposited using the deposition mask, the first virtual line is a line opposed to a dicing line.

[0096] (Method 1) A method for manufacturing an organic EL element including at least one organic layer between a first electrode and a second electrode, the method comprising the steps of: placing a deposition mask having any one of the configurations 1 to 11 and a substrate opposite each other; aligning the substrate and the deposition mask; and depositing a deposition material on the substrate through openings of the deposition mask to form a desired deposition pattern, wherein in the aligning step, a position that becomes a scribe line on the substrate faces the first virtual line of the deposition mask. EXAMPLES

[0097] Examples are shown below. However, the present invention is not limited to these. Unless otherwise specified, the terms used in the present embodiment are the same as those used in the embodiment, and redundant explanations will be omitted.

[0098] [Example 1] The deposition mask 1 of FIG. 2(a) of the present disclosure was placed opposite the substrate, and a co-deposition film of Ag / Mg was formed at a ratio of Ag:Mg=1:1 using a vacuum deposition apparatus to form a 20 nm film. The deposition blur of this deposition film was observed using an optical microscope. The distance between the deposition mask and the substrate, the TS distance, and OFFSED are shown in Table 1.

[0099] [Table 1]

[0100] [Example 2] The deposition mask of FIG. 2(c) of the present disclosure was placed opposite the substrate, and tris(8-hydroxyquinolinato)aluminium (hereinafter, Alq3) was deposited to a thickness of 40 nm using a vacuum deposition apparatus. The deposition blur of this deposition film was observed using an optical microscope. The distance between the deposition mask and the substrate, the TS distance, and the OFFSED are shown in Table 2.

[0101] [Table 2]

[0102] [Example 3] to [Example 10] Except for changing the deposition mask, a co-deposition film or a single film was formed in the same manner as in Examples 1 and 2, and the state of deposition blur was observed using an optical microscope. Table 3 shows the respective deposition masks.

[0103] [Table 3]

[0104] [Comparative Example 1] to [Comparative Example 3] A co-evaporation film or a single film was formed in accordance with Example 1 or Example 2, except that the deposition masks of FIGS. 12(a) to 12(c) were used, and the state of deposition blur was observed using an optical microscope.

[0105] The deposition mask shown in FIG. 12(a) does not have a dummy opening, and has only an opening 2 which is an effective opening. The deposition mask shown in FIG. 12(b) has a dummy opening 3 between the opening 2 and an end of the deposition mask. In FIG. 12(b), the distance between the opening 2 and the virtual line 4 is greater than the distance D between the dummy opening 3 and the virtual line 4 in the second direction Y. The deposition mask shown in FIG. 12(c) is similar to the deposition mask shown in FIG. 12(b) in that it has a dummy opening 3 between the opening 2 and an end of the deposition mask. In FIG. 12(c), the deposition mask differs from Examples 1 to 8 and Comparative Example 2 in that the distance L between the opening 2 and the virtual line 4 is equal to the distance D between the dummy opening 3 and the virtual line 4 in the second direction Y.

[0106] The above-mentioned Examples 1 to 8 and Comparative Examples 1 to 3 were evaluated for the following points. As Evaluation 1, the presence or absence of deposition blur in the outermost opening 2 in the opening region (opening 2 adjacent to dummy opening 3 in Examples 1 to 8 and Comparative Examples 2 and 3) was evaluated. As Evaluation 2, the deposition position of the deposition material formed into a film was observed through the dummy opening 3 to evaluate the presence or absence of deposition on the scribe line. As for Comparative Example 1 without a dummy opening, the deposition position of the deposition material formed into a film was observed through the opening 2 adjacent to the dummy opening.

[0107] Table 4 shows the shape of each deposition mask, the material used for the deposition, the TS distance, and the results of evaluation items 1 and 2.

[0108] [Table 4]

[0109] In this disclosure, the evaluation method for evaluation item 1 was to mark "present" when deposition blur spread 20 μm or more outside the edge of the effective deposition area (area where deposition was expected) on the substrate. The evaluation method for evaluation item 2 was to mark the presence or absence of deposition material actually deposited on the scribe line.

[0110] As shown in Table 4, when the deposition masks of Examples 1 to 8 were used, it was confirmed that the deposition blur was less than 20 μm even in the outermost openings 2 where the deposition blur is expected to be the largest in the opening region W. On the other hand, in Comparative Example 1 which did not have the dummy openings 3, the deposition blur was 20 μm or more.

[0111] Furthermore, deposition of the deposition material on the scribe lines was not observed when the deposition masks of Examples 1 to 8 were used. On the other hand, deposition of the deposition material on the scribe lines was observed in Comparative Example 1 having no dummy opening 3, and in Comparative Examples 2 and 3 in which the distance from the dummy opening 3 to the virtual line 4 was equal to or less than the distance L from the opening 2 to the virtual line 4.

[0112] Therefore, this example confirmed that deposition blurring caused by deviation in rigidity in the deposition mask plane can be alleviated by depositing the deposition material using the deposition mask of the present disclosure. It was also confirmed that deposition of the deposition material on the scribe line can be reduced by depositing the deposition material using the deposition mask of the present disclosure. [Explanation of symbols]

[0113] 1. Deposition mask 2 aperture 3 Dummy opening 4 Virtual Line W opening area

Claims

1. an opening region having a first opening and a second opening; a third opening disposed outside the opening region, The first opening and the second opening are arranged along a first virtual line extending in a first direction, the third opening is disposed between the first opening and an end of the deposition mask in the first direction, a distance between the first opening and the first virtual line in a second direction perpendicular to the first direction is shorter than a distance between the third opening and the first virtual line.

2. an opening region including a first opening having a first side parallel to a first direction and a second side parallel to a second direction perpendicular to the first direction, and a second opening arranged alongside the first opening in the first direction; a third opening disposed in the first direction with respect to the first opening, the third opening is disposed between the opening region and an edge of the deposition mask, If a line adjacent to the first opening and extending in the first direction is defined as a first virtual line, a distance between the first opening and the first virtual line in the second direction is shorter than a distance between the third opening and the first virtual line.

3. the opening region has a fourth opening, The deposition mask according to claim 1 , wherein the fourth opening is disposed adjacent to the first opening across the first virtual line.

4. The deposition mask according to claim 3 , wherein the fourth opening is disposed at a position overlapping with the first opening in the second direction.

5. the opening region has a fifth opening arranged alongside the fourth opening in the first direction, The deposition mask according to claim 3 , wherein the fifth opening is adjacent to the second opening across the first virtual line.

6. When a line adjacent to the first opening on the opposite side of the first virtual line and parallel to the first virtual line is defined as a second virtual line, The deposition mask according to claim 1 , wherein the third opening is located between the first virtual line and the second virtual line.

7. When a line adjacent to the first opening on the opposite side of the first virtual line and parallel to the first virtual line is defined as a second virtual line, 3. The deposition mask according to claim 1, wherein in the second direction, a shorter distance between the first opening and the first virtual line and a distance between the first opening and the second virtual line is shorter than a distance between the third opening and the second virtual line.

8. The deposition mask according to claim 6 , wherein the second opening is located between the first imaginary line and the second imaginary line.

9. When a line adjacent to the first opening on the opposite side of the first virtual line and parallel to the first virtual line is defined as a second virtual line, the opening region has a plurality of openings between the first virtual line and the second virtual line, 3. The deposition mask according to claim 1, wherein, in the second direction, the shorter of a distance between the third opening and the first virtual line and a distance between the third opening and the second virtual line is longer than a shortest distance between the multiple openings and the first virtual line and is longer than a shortest distance between the multiple openings and the second virtual line.

10. 3. The deposition mask according to claim 1, wherein the first opening and the second opening are effective openings, and the third opening is a dummy opening.

11. 3. The deposition mask according to claim 1, wherein in a dicing process of cutting a substrate on which a material has been deposited using the deposition mask, the first virtual line is a line opposite to a dicing line.

12. A method for manufacturing an organic EL element including at least one organic layer between a first electrode and a second electrode, comprising the steps of: A step of placing the deposition mask according to claim 1 or 2 and a substrate opposite each other; aligning the substrate and the deposition mask; forming a desired deposition pattern on the substrate by depositing a deposition material through the openings of the deposition mask; In the step of aligning, a position that will become a scribe line on the substrate and the first virtual line of the deposition mask are positioned opposite each other.

Images