Vapor deposition mask, manufacturing method of vapor deposition mask, and manufacturing method of light emitting device

Abstract

To provide a technique advantageous in repeated use of a vapor deposition mask.SOLUTION: A vapor deposition mask includes: a base material provided with a plurality of openings; and a material layer that contains a material different from the base material and is arranged on an inner wall of the base material facing each of the plurality of openings. The material layer has a concave-convex shape in a portion facing the inner wall.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a deposition mask, a method for manufacturing a deposition mask, and a method for manufacturing a light-emitting device. [Background technology]

[0002] Light-emitting devices including light-emitting elements using organic electroluminescence (EL) elements are known. Patent Document 1 discloses a deposition mask having an uneven shape on the inner wall facing the opening for passing deposition particles. When forming a material film on a substrate to be deposited, the material particles that reach the inner wall of the opening of the deposition mask are supported by the protrusions that make up the uneven shape and are stably deposited on the inner wall, thereby preventing the deposited film deposited on the inner wall from peeling off and adhering to the substrate to be deposited as foreign matter. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-184708 Summary of the Invention [Problem to be solved by the invention]

[0004] Increasing the resolution of light-emitting devices requires increasing the resolution of deposition masks used in their manufacture. However, high-resolution deposition masks are expensive to manufacture, so they are required to be reused. Reusing a deposition mask means removing the material film deposited on the deposition mask after deposition and reusing it. In the configuration described in Patent Document 1, when removing the material film deposited on the deposition mask, some of the material film may remain on the protrusions. Reusing a deposition mask with a remaining material film may result in further deposition on the remaining material film, resulting in the formation of abnormally grown portions with locally thickened layers. These abnormally grown portions may impede the passage of deposition particles and may be a source of particle generation, resulting in defective patterns of the material film formed on the deposition substrate.

[0005] An object of the present invention is to provide a technique that is advantageous for repeated use of a deposition mask. [Means for solving the problem]

[0006] In view of the above-described problems, a vapor deposition mask according to an embodiment of the present invention is a vapor deposition mask having a substrate with a plurality of openings, wherein a material layer made of a material different from that of the substrate is disposed on an inner wall of the substrate facing each of the plurality of openings, and the material layer has an uneven shape in a portion facing the inner wall. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique that is advantageous for repeated use of a deposition mask. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view showing an example of the configuration of a deposition mask according to the present embodiment. [Figure 2] 2A and 2B are a plan view and a cross-sectional view showing an example of the configuration of the deposition mask of FIG. 1. [Figure 3] FIG. 2 is a cross-sectional view showing an example of the configuration of the deposition mask of FIG. 1. [Figure 4] FIG. 2 is a cross-sectional view showing an example of the configuration of the deposition mask of FIG. 1. [Figure 5] FIG. 10 is a cross-sectional view showing a vapor deposition mask of a comparative example. [Figure 6] FIG. 10 is a cross-sectional view showing a vapor deposition mask of a comparative example. [Figure 7] FIG. 2 is a cross-sectional view showing an example of the configuration of a pixel of a light-emitting device manufactured using the deposition mask of the present embodiment. [Figure 8] 8 is a diagram showing an example of an image forming apparatus using the light emitting device of FIG. 7. [Figure 9] 8 is a diagram showing an example of a display device using the light-emitting device of FIG. 7. [Figure 10] FIG. 8 is a diagram showing an example of a photoelectric conversion device using the light-emitting device of FIG. [Figure 11] 8A to 8C are diagrams illustrating examples of electronic devices using the light-emitting device in FIG. 7. [Figure 12] 8 is a diagram showing an example of a display device using the light-emitting device of FIG. 7. [Figure 13] FIG. 8 is a diagram showing an example of a lighting device using the light-emitting device of FIG. 7. [Figure 14] 8 is a diagram showing an example of a moving object using the light emitting device of FIG. 7. [Figure 15] FIG. 8 is a diagram showing an example of a wearable device using the light-emitting device of FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] A deposition mask according to an embodiment of the present disclosure will be described with reference to Figures 1(a) to 6(d). First, problems associated with repeated use of a deposition mask of a comparative example will be described using Figures 5(a), 5(b), and 6(a) to 6(d), and then a deposition mask according to this embodiment will be described. Here, repeated use of a deposition mask means that after a material film is deposited on the deposition mask several to several tens of times, the material film deposited on the deposition mask is removed from the deposition mask and the mask is reused.

[0011] Increasing the resolution of light-emitting devices, including light-emitting elements using organic electroluminescence (EL) elements, necessitates increasing the resolution of deposition masks used in the manufacture of light-emitting devices. Deposition using a deposition mask is used to form organic layers, including light-emitting layers, in each of the multiple pixels in a light-emitting device. As the resolution of pixels (light-emitting elements) in light-emitting devices increases, the areas where the deposition material constituting the organic layer is applied become smaller. This requires deposition masks with openings corresponding to pixels, each measuring a few micrometers in size. For example, semiconductor substrates, such as silicon, processed using semiconductor processes are used as deposition masks with such minute openings. Using semiconductor processes makes it possible to process semiconductor substrates with high precision and fabricate deposition masks. However, using semiconductor processes increases the manufacturing cost per deposition mask. Therefore, reusable deposition masks are needed.

[0012] 5(a) and 5(b) show cross-sectional views of a deposition mask 201 of a comparative example fabricated by processing single-crystal silicon. FIG. 5(b) is an enlarged view of a portion 250 of the deposition mask 201 shown in FIG. 5(a). The deposition mask 201 has a plurality of openings 205 for allowing deposition particles 208 to pass through. As shown in FIGS. 5(a) and 5(b), the deposition particles 208 enter the deposition mask 201 from the lower side. In other words, in the configuration shown in FIGS. 5(a) and 5(b), a deposition source is disposed below the deposition mask 201, and a deposition substrate on which a deposition material is formed is disposed above the deposition mask. An inner wall 206 of the deposition mask 201 facing the openings 205 has an uneven shape formed by processing silicon, which is the base material 221 of the deposition mask 201.

[0013] The uneven shape provided on the inner wall 206 of the base material 221 of the deposition mask 201 can be formed by, for example, the Bosch process. In the Bosch process, etching and forming a protective film are repeated on the single crystal silicon that is the base material 221 of the deposition mask 201. As a result, a periodic uneven shape is formed on the inner wall 206 facing the opening 205 of the deposition mask 201.

[0014] FIG. 6(a) is a diagram showing a state in which the deposition material 210 is deposited on the inner wall 206 facing the opening 205 of the deposition mask 201. FIGS. 6(b) to 6(d) are enlarged views of a portion 251 shown in FIG. 6(a). Some of the deposition particles 208 incident on the deposition mask 201 from a deposition source disposed below the deposition mask 201 pass through the opening 205 and form a film on a deposition target substrate disposed below the deposition mask. Other parts of the deposition particles 208 are also deposited on the deposition mask 201, such as the inner wall 206. The inner wall 206 of the deposition mask 201 has an uneven shape. Therefore, the deposition particles 208 that reach the inner wall 206 of the opening 205 of the deposition mask 201 are supported by the protrusions 211 that constitute the uneven shape, and are stably deposited on the inner wall 206. As a result, the deposition material 210 deposited on the inner wall 206 of the deposition mask 201 is prevented from peeling off and adhering to the deposition substrate as foreign matter.

[0015] Here, consider a case where the deposition material 210 deposited on the deposition mask 201 is removed and the deposition mask 201 is reused. For example, the deposition material 210 can be removed by immersing the deposition mask 201 in an etching solution 241 that can dissolve the deposition material 210. However, when the deposition mask 201 is immersed in the etching solution 241, as shown in FIG. 6( b), air bubbles 213 present in the etching solution 241 may enter recesses 212 that form the uneven shape of the inner wall 206 of the deposition mask 201. If the air bubbles 213 enter the recesses 212, the air bubbles 213 may prevent the etching solution 241 from penetrating deep into the recesses 212. As shown in FIG. 6( c), some of the deposition material 210 may remain in the recesses 212.

[0016] If the deposition mask 201 is reused while the deposition material 210 remains in the recesses 112, as shown in FIG. 6( d ), a film of the deposition material 210 is further formed on the remaining deposition material 210, which makes it more likely for the deposition material 210 to grow abnormally. The abnormally grown portion 217, where the deposition material 210 has grown abnormally, has a locally thick film thickness. Therefore, when the deposition particles 208 pass through the opening 205, the abnormally grown portion 217 may block a portion of the deposition particles 208, which may prevent the deposition material 210 from being deposited at a desired position on the deposition target substrate. Furthermore, the abnormally grown portion 217 is prone to peeling off due to the locally increased thickness, and the peeled film may become foreign matter.

[0017] When the base material 221 of the deposition mask 201 is processed to form an uneven shape on the inner wall 206 facing the opening 205 provided in the deposition mask 201, the deposition material 210 is likely to remain in the recesses 212 of the inner wall 206 when the deposition mask 201 is immersed in an etching solution 241 for reuse. Therefore, when the deposition material 210 deposited on the deposition mask 201 is removed and the deposition mask 201 is reused, problems such as a decrease in the yield of the deposition process may occur. The deposition mask 101 of this embodiment, which is designed to prevent such problems, will be described below.

[0018] FIG. 1( a) is a diagram showing the periphery of an inner wall 106 facing an opening 105 of a deposition mask 101 of this embodiment. A base material 121 of the deposition mask 101 has openings 105 for allowing deposition particles 108 to pass through to a deposition target substrate. In this embodiment, a material layer 104 made of a material different from that of the base material 121 is disposed on the inner wall 106 of the base material 121 facing each of the multiple openings 105. The material layer 104 can be disposed so as to cover the inner wall 106 of the base material 121. Like the inner wall 206 of a deposition mask 201 of the comparative example, the material layer 104 has an uneven shape in the portion facing the inner wall 106 of the base material 121.

[0019] As shown in FIG. 1( a), the deposition particles 108 pass through the openings 105 in the deposition mask 101 and are deposited not only on the deposition substrate but also on the deposition mask 101, such as a material layer 104 having an uneven shape. When removing the deposition material 110 deposited on the deposition mask 101 and reusing the deposition mask 101, the deposition mask 101 is immersed in an etching solution 141 capable of dissolving the deposition material 110. At this time, as shown in FIG. 1( b), bubbles 113 present in the etching solution 141 may enter the recesses 112 that constitute the uneven shape of the material layer 104 disposed on the inner wall 106 of the base material 121 of the deposition mask 101. The generation of the bubbles 113 is similar to that when the deposition mask 201 of the comparative example described above is immersed in the etching solution 241 for reuse.

[0020] However, as shown in FIG. 1( c), by immersing the material layer 104 in an etching solution 141 that can remove the material layer 104 without significantly damaging the substrate 121 of the deposition mask 101, the etching solution 141 gradually dissolves the material layer 104. As a result, the etching solution 141 cannot penetrate into the recesses 112 where the bubbles 113 exist, but can dissolve the material layer 104 from the recesses 112 where the bubbles 113 do not exist. As the etching progresses further, as shown in FIG. 1( d), it becomes possible to remove the deposition material 110 along with the material layer 104. For example, by continuing the etching until the material layer 104 is completely dissolved, the material layer 104 and the deposition material 110 deposited on the material layer 104 can be completely removed.

[0021] In this embodiment, a material layer 104 having an uneven shape and made of a material different from the base material 121 of the deposition mask 101 is formed on the surface of the base material 121, including the inner walls 106 facing the openings 105 provided in the base material 121 of the deposition mask 101. Thereafter, after using the deposition mask 101 for several to several tens of depositions, the deposition mask 101 is immersed in an etching solution 141 capable of removing the material layer 104. This allows the material layer 104 to be peeled off from the used deposition mask 101, and the material layer 104 and the deposition material 110 deposited on the deposition mask 101 to be removed without residue. The used deposition mask 101 refers to a deposition mask 101 that has been used to deposit a deposition material. As a result, it is possible to provide a reusable, high-definition deposition mask 101 in which a decrease in yield in the deposition process is suppressed.

[0022] Here, the etching solution 141 is not limited to a solution capable of removing (peeling off) only the material layer 104. For example, if the damage to the deposition mask 101 is very slight and the deposition mask 101 can be reused, such a solution can be selected as the etching solution 141. In other words, if the etching rate of the material layer 104 is higher than that of the substrate 121, such a solution can be used as the etching solution 141. For example, a solution having an etching selectivity of 100 or more between the material layer 104 and the substrate 121 may be used as the etching solution 141. Furthermore, for example, the etching selectivity of the etching solution 141 between the material layer 104 and the substrate 121 may be 500 or more, or 1000 or more.

[0023] The deposition mask 101 of this embodiment will be further described below with reference to Figures 2(a) to 2(d). Figure 2(a) is a plan view of the deposition mask 101 of this embodiment, and Figure 2(b) is a cross-sectional view taken along line A-A' in Figure 2(a). Figure 2(c) is an enlarged view of a portion 151 shown in Figure 2(b), and Figure 2(d) is a further enlarged view of Figure 2(c) for explaining the structure of the material layer 104.

[0024] The deposition mask 101 of this embodiment is formed by processing a semiconductor substrate such as single-crystal silicon using a semiconductor process. The deposition mask 101 may have an internal region 102 provided with a plurality of openings 105 (openings corresponding to pixels of a light-emitting device: pixel openings) for passing deposition particles 108, and an external region 103 surrounding the internal region 102. Depending on the semiconductor substrate from which the deposition mask 101 is formed, the external region 103 may have a circular outer shape, an outer diameter of 100 to 300 mm, and a thickness of 100 to 1000 μm, such as 725 μm or 775 μm. The internal region 102 may have a thickness of 1 to 100 μm. The base material 121 of the deposition mask 101 is not limited to a semiconductor substrate such as single-crystal silicon. A silicon-on-insulator (SOI) substrate may be used as the base material 121. For example, the substrate 121 may be made of glass, a metal containing a magnetic material, ceramic, or resin. The shape of the deposition mask 101 is not limited to a circle and may be other shapes such as a rectangle. For example, the inner region 102 and the outer region 103 may be made of different materials.

[0025] The internal region 102 of the deposition mask 101 is provided with, for example, a plurality of pixel areas 107 corresponding to a plurality of chips (light-emitting devices). Each pixel area 107 is provided with a plurality of openings 105 corresponding to the pixels of the light-emitting device. The shape of the openings 105 may be circular or rectangular. The shape of the openings 105 can be varied depending on the shape of the pixels to be formed on the deposition substrate 109. The size of the openings 105 may be defined by their width or area. For example, the size may be defined by the diameter when the opening shape is circular, or the diagonal length when the opening shape is rectangular. For example, the width of the openings 105 can be as small as several micrometers. In the configuration shown in FIG. 2(b), the cross-sectional shape of the opening 105 is shown as having the same opening width on both the deposition substrate 109 side and the deposition source side facing it. However, the opening may have a tapered shape, for example, with the opening width wider on the deposition source side.

[0026] A material layer 104 having an uneven shape and made of a material different from that of the substrate 121 of the deposition mask 101 is formed on the surface of the deposition mask 101, including the inner wall 106 facing the opening 105 of the substrate 121 of the deposition mask 101. The material layer 104 can be formed by, for example, atomic layer deposition (ALD). The ALD method can conformally deposit the material layer 104 on the substrate 121, so that the material layer 104 can maintain a surface shape substantially identical to that of the substrate 121 before deposition. However, the formation of the material layer 104 is not limited to the ALD method, and an appropriate deposition method can be selected depending on the shape of the deposition mask 101. The material layer 104 may be formed by, for example, chemical vapor deposition (CVD) or sputtering.

[0027] FIG. 2(d) is an enlarged view of the material layer 104 disposed on the inner wall 106 facing the opening 105 of the substrate 121 of the deposition mask 101. The material layer 104 includes a region 115 and a region 114 disposed between the region 115 and the inner wall 106 of the substrate 121. In this case, the regions 114 and 115 may have different densities. More specifically, the density of the region 114 may be greater than the film density of the region 115. Furthermore, the ratio of the depth to the width of the recesses 112 of the uneven shape of the material layer 104 may be 1 or greater. That is, as shown in FIG. 2(d), when the width of the recesses 112 in the region 115 is a and the depth is b, b / a may be greater than 1. Here, the width a refers to the minimum opening width of the recesses 112 when viewed from above. By configuring the material layer 104 in this manner, the vapor deposition particles 108 do not reach the inner wall 106 or the region 114 of the substrate 121 as a continuous film, but are intermittently deposited in the region 115. This can make it easier to remove the deposited vapor deposition material 110 without leaving any residue.

[0028] Furthermore, to prevent the recesses 112 in the region 115 from being blocked by the deposition material 110, the depth b of the region 115 may be greater than the thickness of the deposition material 110 to be deposited, and the width a of the recesses 112 in the region 115 may be greater than the thickness of the deposition material 110. For example, the width a and the depth b of the recesses 112 in the region 115 may be, for example, 1 to 50 times the thickness of the deposition material 110, or may be, for example, 5 to 20 times the thickness of the deposition material 110. For example, if the thickness of the deposition material 110 formed on the deposition substrate 109 is 20 nm, the width a and the depth b of the recesses 112 may be, for example, 20 to 1000 nm, or 100 to 400 nm, respectively.

[0029] 3, the density of the regions 114 and 115 may be defined as the amount of voids 116 in any area (within the rectangle surrounded by the dotted line in the figure) of the regions 114 and 115. A high density indicates a low amount of voids 116.

[0030] The material layer 104 may be composed of, for example, a layer mainly composed of aluminum oxide crystals (a layer composed of alumina hydrate) in which a concave-convex structure is formed by the aluminum oxide crystals. Examples of a method for producing such a material layer 104 include the following steps: First, a base material 121 of the deposition mask 101 having a plurality of openings 105 formed therein is prepared. When forming a new deposition mask 101, the openings 105 are formed in a semiconductor substrate such as single-crystal silicon using a semiconductor process or the like. When using the deposition mask 101 repeatedly, for example, the material layer 104 (and the deposition material 110) is peeled off from a used deposition mask 101 to prepare a base material 121 of the deposition mask 101 having a plurality of openings 105 formed therein. Next, aluminum oxide is deposited as the material layer 104 on the surface of the base material 121 of the deposition mask 101 using an ALD method. After forming the aluminum oxide film, the deposition mask 101 including the material layer 104 (aluminum oxide) is immersed in warm water at a temperature of about 70°C or higher and 100°C or lower to form the textured pattern. This allows the material layer 104 to have a textured pattern. The thickness and textured pattern of the aluminum oxide crystals (alumina hydrate) formed in this way can be arbitrarily changed by changing the thickness of the aluminum oxide film, the temperature of the warm water, and the immersion time. For example, a 100-nm aluminum oxide film is formed on the surface of the substrate 121 and immersed in 80°C warm water for 30 minutes. This allows the material layer 104 to have a thickness of 400 to 500 nm and an average opening width of about 100 to 200 nm.

[0031] As shown in this embodiment, when a deposition mask 101 having a base material 121 made of silicon and a material layer 104 made of aluminum oxide (alumina hydrate) is used repeatedly, a solution containing approximately 3 to 4% hydrochloric acid can be used as the etching solution 141. Immersing the deposition mask 101 used for deposition in a solution containing hydrochloric acid for approximately several tens of seconds makes it possible to peel off the material layer 104 without damaging the base material 121 of the deposition mask 101. After peeling off the material layer 104 and the deposition material 110, a film of aluminum oxide can be formed again on the surface of the deposition mask 101 by ALD or the like, followed by hot water treatment, thereby forming the material layer 104 again. Therefore, the deposition mask 101 can be reused repeatedly.

[0032] In this manner, in this embodiment, the deposition material 110 deposited on the deposition mask 101 can be removed without leaving any residue. As a result, it is possible to provide a high-definition deposition mask 101 that can be used repeatedly for a long period of time.

[0033] In the above-described embodiment, the material layer 104 is made of aluminum oxide crystals (alumina hydrate). However, the material used for the material layer 104 is not limited to alumina hydrate. For example, aluminum oxide or titanium oxide having a porous surface formed by anodization may be used for the material layer 104. A solution containing phosphoric acid may be used as the etching solution 141 for anodized aluminum oxide, and a solution containing hydrogen peroxide may be used for anodized titanium oxide. Alternatively, an organic polymer having a porous surface may be used for the material layer 104. In this case, an organic solvent may be used as the etching solution 141. By selecting an etching solution 141 that does not damage the substrate 121 of the deposition mask 101, the deposition material 110 adhering to the deposition mask 101 can be removed without leaving any residue. This makes it possible to provide a high-definition deposition mask 101 that can be used repeatedly for a long period of time.

[0034] Fig. 4 is a diagram showing a modified example of the deposition mask 101 shown in Fig. 2(b). Compared to Fig. 2(b), the range in which the material layer 104 is formed is different from the configuration shown in Fig. 2(b).

[0035] The material layer 104 shown in FIG. 4 is formed only in an area where the deposition particles 108 are deposited on the deposition mask 101. The deposition mask 101 has a main surface 161 that faces the deposition target substrate 109 and a main surface 162 opposite the main surface 161. In this case, the material layer 104 covers at least a portion of the main surface 162. On the other hand, the material layer 104 does not cover the main surface 161 that faces the deposition target substrate 109. The material layer 104 is not formed on portions of the deposition mask 101 that come into contact with the deposition target substrate 109 or a jig (not shown) for fixing the deposition mask 101 during deposition. This prevents the material layer 104 from peeling off due to contact with the deposition target substrate 109 or the jig. This suppresses the generation of foreign matter such as particles, thereby further improving the yield of the deposition process. 4, a spacer layer or the like may be formed on the main surface 161 of the deposition mask 101 to prevent the deposition mask 101 from sticking to the deposition substrate 109. For example, a fluororesin or the like may be used as the spacer layer.

[0036] 4, a material layer 104 is also formed at a position where the deposition material 110 is to be deposited. Therefore, similar to the above-described embodiment, the deposition material 110 deposited on the deposition mask 101 can be removed without leaving any residue. In other words, it is possible to provide a high-definition deposition mask 101 that can be used repeatedly for a long period of time.

[0037] Here, a light-emitting device including pixels (light-emitting elements) containing organic layers such as a light-emitting layer formed using the vapor deposition mask of this embodiment will be described. Application examples of such a light-emitting device in image forming apparatuses, display devices, photoelectric conversion devices, electronic devices, lighting devices, mobile objects, and wearable devices will be described with reference to FIGS. 7(a) and 7(b) to 15(a) and 15(b). The pixels (hereinafter sometimes referred to as light-emitting elements, sub-pixels, etc.) arranged in the light-emitting device will be described as including organic light-emitting elements (OLEDs), such as organic EL elements using an organic light-emitting material. Details of each component arranged in the pixel of the light-emitting device will be first described, and then application examples will be described.

[0038] An organic light-emitting device according to one embodiment of the present invention has a first electrode, a second electrode, and an organic compound layer disposed between these electrodes. One of the first electrode and the second electrode is an anode and the other is a cathode. In the organic light-emitting device of this embodiment, the organic compound layer may be a single layer or a laminate consisting of multiple layers, as long as it has an emitting layer. If the organic compound layer is a laminate consisting of multiple layers, the organic compound layer may include, in addition to the 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 emitting layer may also be a single layer or a laminate consisting of multiple layers. If the emitting layer is a multi-layer, a charge generation layer may be disposed between the emitting layers. The charge generation layer may be composed of a compound having a lower LUMO than the hole transport layer, and the LUMO of the charge generation layer may be lower than the HOMO of the hole transport 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.

[0039] Here, the closer the HOMO and LUMO are to the vacuum level, the higher they are described as being. The LUMO of the charge generation layer being lower than the HOMO of the hole transport layer means that the LUMO of the charge generation layer is closer to the vacuum level than the HOMO of the hole transport layer.

[0040] In this specification, the HOMO and LUMO can be calculated using molecular orbital calculations. The molecular orbital calculations are performed using density functional theory (DFT) or the like, with the functional being B3LYP and the basis set being 6-31G. *It is also the case that the range of graphical designs is Gaussian09(Gaussian09). ,RevisionC.01,MJFrisch,GWTrucks,HBSchlegel,GEScus area, MARobb, JRCheeseman, G. Scalmani, V. Barone, B. Mennucci, G. Petersson, H. Nakatsuji, M. Caricato, X. Li, HPHr atchian, AFIzmaylov, J. Bloino, G. Zheng, JLSonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ish ida,T.Nakajima,Y.Honda,O.Kitao,H.Nakai,T.Vreven,JAMontgomery,Jr.,JEPeralta,F.Ogliaro,M.Bearpark,JJH eyd, E. Brothers, KNKudin, VNStaroverov, T. Keith, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, JCBuran t,SSIyengar,J.Tomasi,M.Cossi,N.Rega,JMMillam,M.Klene,JEKnox,JBCross,V.Bakken,C.Adamo,J.Jaramillo,R. Gomperts,REStratmann,O.Yazyev,AJAustin,R.Cammi,C.Pomelli,JWOchterski,RLMartin,K.Morokuma,VGZakrzews ki,GAVoth,P.Salvador,JJDannenberg,S.Dapprich,ADDaniels,O.Farkas,JBForesman,JVOrtiz,JCioslowski,and DJFox,Gaussian,Inc.,Wallingford CT,2010.)

[0041] The HOMO and LUMO in this specification can be calculated using the ionization potential and band gap. The HOMO can be estimated by measuring the ionization potential. The ionization potential can be measured by dissolving the compound to be measured in a solvent such as toluene and using a measuring device such as an AC-3. The band gap can be measured by dissolving the compound to be measured in a solvent such as toluene and irradiating it with excitation light. The band gap can be measured by measuring the absorption edge of the excitation light. Alternatively, the compound to be measured can be deposited on a substrate such as glass and irradiated with excitation light on the deposited film. The band gap can be measured by measuring the absorption edge of the absorption spectrum where the deposited film absorbs the excitation light.

[0042] The LUMO can be calculated using the band gap and ionization potential: subtracting the ionization potential from the band gap gives the LUMO.

[0043] The LUMO can also be estimated from the reduction potential. For example, the one-electron reduction potential can be estimated using CV (cyclic volmetry) measurements. CV measurements are performed, for example, in a 0.1 M tetrabutylammonium perchlorate solution in DMF, with an Ag / Ag reference electrode. + The LUMO can be estimated by adding -4.8 eV, the difference between the reduction potential of the compound and that of ferrocene, to the reduction potential of the compound obtained.

[0044] When the organic compound according to this embodiment is included in the light-emitting layer, the light-emitting layer may be composed solely of the organic compound according to this embodiment, or may be composed of the organometallic complex according to this embodiment and other compounds. When the light-emitting layer is composed of the organometallic complex according to this embodiment and other compounds, the organic compound according to this embodiment may be used as a host or a guest in the light-emitting layer. It may also be used as an assist material that can be included in the light-emitting layer. Here, the host is the compound with the largest mass ratio among the compounds that constitute the light-emitting layer. The guest is the compound that is smaller in mass ratio than the host among the compounds that constitute the light-emitting layer and is responsible for the primary emission of light. The assist material is the compound that is smaller in mass ratio than the host among the compounds that constitute the light-emitting layer and assists the guest in emitting light. The assist material is also called a second host. The host material can also be called the first compound, and the assist material can also be called the second compound.

[0045] When the organic compound according to one embodiment of the present invention is used as a guest in the light-emitting layer, the concentration of the guest may be 0.01% by mass or more and 20% by mass or less, or even 0.1% by mass or more and 10% by mass or less, based on the total mass of the light-emitting layer. The guest is also called a dopant.

[0046] The organometallic complex according to this embodiment can be used as a constituent material of an organic compound layer other than the light-emitting layer that constitutes the organic light-emitting device of this embodiment. Specifically, it may be used as a constituent material of an electron transport layer, an electron injection layer, a hole transport layer, a hole injection layer, a hole blocking layer, etc. In this case, the emission color of the organic light-emitting device is not limited to red. More specifically, it may emit white light or an intermediate color.

[0047] If necessary, conventionally known low-molecular-weight and high-molecular-weight hole-injecting or hole-transporting compounds, host compounds, light-emitting compounds, electron-injecting or electron-transporting compounds, etc. may be used together. Examples of these compounds are listed below.

[0048] Suitable hole injection and transport materials are those with high hole mobility that facilitates hole injection from the anode and transports the injected holes to the light-emitting layer. Furthermore, materials with high glass transition temperatures are suitable to reduce film quality degradation, such as crystallization, in organic light-emitting devices. Examples of low-molecular-weight and high-molecular-weight materials with hole injection and transport properties include triarylamine derivatives, arylcarbazole derivatives, phenylenediamine derivatives, stilbene derivatives, phthalocyanine derivatives, porphyrin derivatives, poly(vinylcarbazole), poly(thiophene), and other conductive polymers. Furthermore, the above-mentioned hole injection and transport materials are also suitable for use in electron blocking layers. Specific examples of compounds that can be used as hole injection and transport materials are listed below, but are not limited to these.

[0049] [ka]

[0050] Among the hole transport materials listed above, HT16 to HT18 can reduce the driving voltage when used in a layer in contact with the anode. HT16 is widely used in organic light-emitting devices. HT2, HT3, HT4, HT5, HT6, HT10, and HT12 may be used in an organic compound layer adjacent to HT16. Furthermore, multiple materials may be used in one organic compound layer.

[0051] Examples of luminescent materials that are mainly involved in luminescence function include fused ring compounds (e.g., fluorene derivatives, naphthalene derivatives, pyrene derivatives, perylene derivatives, tetracene derivatives, anthracene derivatives, rubrene, etc.), quinacridone derivatives, coumarin derivatives, stilbene derivatives, organoaluminum complexes such as tris(8-quinolinolato)aluminum, iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes, and polymer derivatives such as poly(phenylenevinylene) derivatives, poly(fluorene) derivatives, and poly(phenylene) derivatives.

[0052] Specific examples of compounds that can be used as light-emitting materials are shown below, but the present invention is not limited to these.

[0053] [ka]

[0054] [ka]

[0055] When the light-emitting material is a hydrocarbon compound, it is suitable because it can reduce the decrease in light-emitting efficiency due to exciplex formation and the decrease in color purity due to the change in the emission spectrum of the light-emitting material due to exciplex formation.

[0056] Hydrocarbon compounds are compounds composed only of carbon and hydrogen, and among the above-mentioned exemplary compounds, BD7, BD8, GD5 to GD9, and RD1 are mentioned.

[0057] When the light-emitting material is a fused polycyclic ring containing a five-membered ring, it is suitable because it has a high ionization potential, is resistant to oxidation, and forms a device with a long durability and life. Among the above-mentioned exemplary compounds, BD7, BD8, GD5 to GD9, and RD1 are examples.

[0058] Examples of the light-emitting layer host or light-emitting assist material contained in the light-emitting layer include aromatic hydrocarbon compounds or derivatives thereof, as well as carbazole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, organoaluminum complexes such as tris(8-quinolinolato)aluminum, and organic beryllium complexes.

[0059] Specific examples of compounds that can be used as the light-emitting layer host or light-emitting assist material contained in the light-emitting layer are shown below, but the present invention is not limited to these.

[0060] [ka]

[0061] The host material may be a hydrocarbon compound. A hydrocarbon compound is a compound composed only of carbon and hydrogen, and examples of the above-mentioned compounds include EM1 to EM12 and EM16 to EM27. From the viewpoint of stability, host materials that do not have a carbon-heteroatom bond in the single bond connecting the aryl group units in their structure, such as F3 in Compound 1, are more suitable.

[0062] The electron transporting material can be arbitrarily selected from those capable of transporting electrons injected from the cathode to the light-emitting layer, and is selected taking into consideration the balance with the hole mobility of the hole transporting material, etc. Examples of materials having electron transport properties include oxadiazole derivatives, oxazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, organoaluminum complexes, and fused ring compounds (e.g., fluorene derivatives, naphthalene derivatives, chrysene derivatives, anthracene derivatives, etc.). Furthermore, the above electron transporting materials are also suitable for use in hole-blocking layers.

[0063] Specific examples of compounds that can be used as electron transporting materials are shown below, but the present invention is not limited to these.

[0064] [ka]

[0065] The electron injection material can be selected from those that allow easy electron injection from the cathode, taking into consideration the balance with hole injection properties. Organic compounds include n-type dopants and reducing dopants. Examples include compounds containing alkali metals such as lithium fluoride, lithium complexes such as lithium quinolinol, benzimidazolidene derivatives, imidazolidene derivatives, fulvalene derivatives, and acridine derivatives.

[0066] It can also be used in combination with the above electron transporting material.

[0067] Structure of organic light-emitting element The organic light-emitting element is provided by forming an insulating layer, a first electrode, an organic compound layer, and a second electrode on a substrate. A protective layer, a color filter, a microlens, etc. may be provided on the cathode. When a color filter is provided, a planarizing layer may be provided between the protective layer and the color filter. The planarizing layer may be made of an acrylic resin, etc. The same applies when a planarizing layer is provided between the color filter and the microlens.

[0068] substrate Examples of the substrate include quartz, glass, silicon wafer, resin, and metal. The substrate may also include switching elements such as transistors and wiring patterns, with an insulating layer provided thereon. The insulating layer may be made of any material as long as it allows contact holes to be formed so that wiring patterns can be formed between the first electrode and the substrate, and insulation from unconnected wiring patterns is ensured. For example, the insulating layer may be made of a resin such as polyimide, silicon oxide, silicon nitride, or the like.

[0069] electrode A pair of electrodes can be used as the electrodes. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, the electrode with a higher potential is the anode, and the other is the cathode. It can also be said that the electrode that supplies holes to the light-emitting layer is the anode, and the electrode that supplies electrons is the cathode.

[0070] The anode may be made of a material with a high work function. For example, simple metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, and tungsten, mixtures containing these metals, alloys of these metals, and metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and zinc indium oxide can be used. Conductive polymers such as polyaniline, polypyrrole, and polythiophene can also be used as the anode.

[0071] These electrode materials may be used alone or in combination of two or more. The anode may be composed of one layer or multiple layers.

[0072] When the electrode is used as a reflective electrode, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, or alloys thereof, or laminates thereof can be used. The above materials can also function as a reflective film without functioning as an electrode. Furthermore, when a transparent electrode is used as the electrode, a transparent conductive oxide layer such as indium tin oxide (ITO) or indium zinc oxide can be used, but is not limited to these. Photolithography technology can be used to form the electrode.

[0073] On the other hand, a material with a low work function may be selected as the cathode material. Examples include simple metals such as alkali metals (e.g., lithium), alkaline earth metals (e.g., calcium), aluminum, titanium, manganese, silver, lead, and chromium, as well as mixtures containing these metals. Alternatively, alloys combining these simple metals may be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, and zinc-silver may be used. Metal oxides such as indium tin oxide (ITO) may also be used. These electrode materials may be used alone or in combination. The cathode may have a single-layer or multi-layer structure. Silver may be used as the cathode, and a silver alloy may be used to reduce silver aggregation. The alloy ratio is not important as long as silver aggregation is reduced. For example, the silver:other metal ratio may be 1:1 or 3:1.

[0074] The cathode may be a top-emission element using an oxide conductive layer such as ITO, or a bottom-emission element using a reflective electrode such as aluminum (Al), and is not particularly limited. The method for forming the cathode is not particularly limited, but using a DC or AC sputtering method, for example, can provide good coverage of the formed film and reduce the resistance of the cathode.

[0075] Pixel isolation layer The pixel separation layer may be formed of silicon oxide, such as silicon nitride (SiN), silicon oxynitride (SiON), or silicon oxide (SiO), formed using a chemical vapor deposition (CVD) method. To increase the in-plane resistance of the organic compound layer, the organic compound layer, particularly the hole transport layer, may be thinly formed on the sidewalls of the pixel separation layer. Specifically, the thickness of the organic compound layer on the sidewalls can be thinned by increasing the taper angle of the sidewalls of the pixel separation layer or the thickness of the pixel separation layer, thereby increasing vignetting during deposition.

[0076] On the other hand, the sidewall taper angle and film thickness of the pixel separation layer can be adjusted to the extent that voids are not formed in the protective layer formed thereon. By preventing voids from being formed in the protective layer, the occurrence of defects in the protective layer can be reduced. Since the occurrence of defects in the protective layer is reduced, deterioration of reliability such as the occurrence of dark spots and poor conduction of the second electrode can be reduced.

[0077] According to this embodiment, charge leakage to adjacent pixels can be effectively suppressed even if the taper angle of the sidewall of the pixel separation layer is not steep. As a result of this study, it was found that charge leakage can be sufficiently reduced if the taper angle is between 60 degrees and 90 degrees. The thickness of the pixel separation layer may be between 10 nm and 150 nm. Similar effects can also be achieved even if the pixel separation layer is composed only of pixel electrodes without a pixel separation layer. However, in this case, short circuits in organic light-emitting elements can be reduced by making the thickness of the pixel electrode less than half that of the organic layer or by making the edge of the pixel electrode forward tapered at less than 60 degrees.

[0078] Furthermore, even when the first electrode is a cathode and the second electrode is an anode, a wide color gamut and low-voltage operation are possible by forming an electron transport material and a charge transport layer, and an emitting layer on the charge transport layer.

[0079] organic compound layer The organic compound layer may be formed as a single layer or as multiple layers. When multiple layers are present, they may be called hole injection layers, hole transport layers, electron blocking layers, light-emitting layers, hole blocking layers, electron transport layers, electron injection layers, etc., depending on their functions. The organic compound layer is primarily composed of organic compounds but may also contain inorganic atoms or compounds. The organic compound layer may contain, for example, copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, zinc, etc. The organic compound layer may be disposed between the first electrode and the second electrode, or may be disposed in contact with the first electrode and the second electrode. When multiple light-emitting layers are present, a charge generation section may be disposed between the first and second light-emitting layers. The charge generation section may contain an organic compound having a lowest unoccupied molecular orbital energy (LUMO) of -5.0 eV or less. The same applies when a charge generation section is disposed between the second and third light-emitting layers.

[0080] protective layer A protective layer may be provided on the cathode. For example, by adhering glass with a moisture absorbent on the cathode, the penetration of moisture and other contaminants into the organic compound layer can be reduced, thereby reducing the occurrence of display defects. In another embodiment, a passivation layer such as silicon nitride may be provided on the cathode to reduce the penetration of moisture and other contaminants into the organic compound layer. For example, after forming the cathode, the cathode may be transferred to another chamber without breaking the vacuum, and a 2 μm-thick silicon nitride may be formed by CVD to serve as a protective layer. After forming the protective layer by CVD, a protective layer may be formed by atomic layer deposition (ALD). The material of the protective layer formed by ALD is not limited, and may be silicon nitride, silicon oxide, aluminum oxide, or the like. Silicon nitride may be further formed by CVD on the protective layer formed by ALD. The protective layer formed by ALD may have a thickness smaller than that of the protective layer formed by CVD. Specifically, the thickness of the protective layer formed by ALD may be 50% or less, or even 10% or less, of the protective layer formed by CVD.

[0081] Color filters A color filter may be provided on the protective layer. For example, a color filter taking into consideration the size of the organic light-emitting element may be provided on another substrate, and the substrate on which the color filter is formed may be bonded to the substrate on which the organic light-emitting element is provided. Alternatively, for example, a color filter may be patterned on the above-mentioned protective layer using photolithography technology. The color filter may be made of a polymer.

[0082] planarization layer A planarization layer may be disposed between the color filter and the protective layer. The planarization layer is provided for the purpose of reducing the unevenness of the layers below the planarization layer. It may also be called a material resin layer without limiting the purpose. The planarization layer may be composed of an organic compound, and may be a low molecular weight or a high molecular weight. In consideration of reducing the unevenness, a high molecular weight organic compound may be used for the planarization layer.

[0083] The planarization layers may be provided above and below the color filter. In this case, the constituent materials of the planarization layers may be the same or different. Specific examples of the material for the planarization layer include polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin.

[0084] Microlenses The organic light-emitting device may have an optical component such as a microlens on its light-emitting side. The microlens may be made of acrylic resin, epoxy resin, or the like. The microlens may be intended to increase the amount of light extracted from the organic light-emitting device or to control the direction of the extracted light. The microlens may have a hemispherical shape. When the microlens has a hemispherical shape, among the tangents to the hemisphere, there is a tangent that is parallel to the insulating layer, and the point of contact between this tangent and the hemisphere is the vertex of the microlens. The vertex of the microlens can be determined in the same way in any cross-sectional view. In other words, among the tangents to the semicircle of the microlens in the cross-sectional view, there is a tangent that is parallel to the insulating layer, and the point of contact between this tangent and the semicircle is the vertex of the microlens.

[0085] It is also possible to define the midpoint of a microlens. In the cross section of the microlens, a line segment is imagined from the point where an arc shape ends to the point where another arc shape ends, and the midpoint of this line segment can be called the midpoint of the microlens. The cross section for determining the vertex and midpoint may be a cross section perpendicular to the insulating layer.

[0086] The microlens has a first surface having a convex portion and a second surface opposite the first surface. The second surface can be disposed closer to the functional layer (light-emitting layer) than the first surface. To achieve this configuration, it is necessary to form the microlens on the light-emitting device. If the functional layer is an organic layer, high-temperature processes can be avoided in the microlens manufacturing process. Furthermore, if the second surface is disposed closer to the functional layer than the first surface, the glass transition temperatures of the organic compounds constituting the organic layer may all be 100°C or higher, and are preferably, for example, 130°C or higher.

[0087] Counter substrate An opposing substrate may be disposed on the planarization layer. The opposing substrate is called an opposing substrate because it is provided at a position corresponding to the aforementioned substrate. The opposing substrate may be made of the same material as the aforementioned substrate. When the aforementioned substrate is defined as a first substrate, the opposing substrate may be a second substrate.

[0088] organic layer The organic compound layers (hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) constituting the organic light-emitting element according to an embodiment of the present disclosure may be formed by the following method.

[0089] The organic compound layer constituting the organic light-emitting device according to the embodiment of the present disclosure can be formed by dry processes such as vacuum deposition, ionization deposition, sputtering, plasma, etc. Alternatively to the dry process, a wet process can be used in which the compound is dissolved in an appropriate solvent and a layer is formed by a known coating method (e.g., spin coating, dipping, casting, LB method, inkjet method, etc.).

[0090] Here, when a layer is formed by a vacuum deposition method or a solution coating method, crystallization is unlikely to occur and the layer has excellent stability over time. When a film is formed by a coating method, the film can be formed by combining it with an appropriate binder resin.

[0091] Examples of the binder resin include, but are not limited to, polyvinylcarbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin.

[0092] These binder resins may be used singly or in combination as homopolymers or copolymers, and may further contain known additives such as plasticizers, antioxidants, and ultraviolet absorbers, as needed.

[0093] Pixel circuit The light-emitting device may have a pixel circuit connected to the light-emitting element. The pixel circuit may be an active matrix type that controls the emission of the first light-emitting element and the second light-emitting element independently. The active matrix type circuit may be voltage-programmed or current-programmed. The drive circuit has a pixel circuit for each pixel. The pixel circuit may have a light-emitting element, a transistor that controls the emission brightness of the light-emitting element, a transistor that controls the emission timing, a capacitor that holds the gate voltage of the transistor that controls the emission brightness, and a transistor for connecting to GND without going through the light-emitting element.

[0094] The light-emitting device has a display region and a peripheral region arranged around the display region. The display region has pixel circuits, and the peripheral region has a display control circuit. The mobility of a transistor constituting the pixel circuit may be lower than the mobility of a transistor constituting the display control circuit.

[0095] The slope of the current-voltage characteristics of the transistors that make up the pixel circuit may be smaller than the slope of the current-voltage characteristics of the transistors that make up the display control circuit. The slope of the current-voltage characteristics can be measured using the so-called Vg-Ig characteristics.

[0096] The transistors that make up the pixel circuit are transistors connected to the light-emitting elements, such as the first light-emitting element.

[0097] pixel An organic light emitting device includes a plurality of pixels, each of which includes sub-pixels that emit different colors, for example, RGB colors.

[0098] A pixel has an area called a pixel aperture that emits light. The pixel aperture may be 15 μm or less, or 5 μm or more. More specifically, it may be 11 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc.

[0099] The spacing between the subpixels may be 10 μm or less, and specifically may be 8 μm, 7.4 μm, or 6.4 μm.

[0100] The pixels may be arranged in a known manner in a plan view. For example, they may be in a stripe arrangement, a delta arrangement, a pentile arrangement, or a Bayer arrangement. The shape of the subpixels in a plan view may be any known shape. For example, they may be rectangular, quadrilaterals such as diamonds, or hexagons. Of course, a shape that is close to a rectangle, rather than an exact shape, is included in the rectangle. The shape of the subpixels and the pixel arrangement may be used in combination.

[0101] Uses of the organic light-emitting device according to embodiments of the present disclosure The organic light-emitting device according to the embodiment of the present disclosure can be used as a component of a display device or a lighting device, and can also be used as an exposure light source for an electrophotographic image forming device, a backlight for a liquid crystal display device, or a light-emitting device having a white light source and a color filter.

[0102] The display device may be an image information processing device that has an image input unit that inputs image information from an area CCD, linear CCD, memory card, etc., has an information processing unit that processes the input information, and displays the input image on the display unit.

[0103] The display unit of the imaging device or inkjet printer may have a touch panel function. The driving method of this touch panel function may be an infrared method, a capacitance method, a resistive film method, or an electromagnetic induction method, and is not particularly limited. The display device may also be used in the display unit of a multifunction printer.

[0104] Next, further explanation will be given with reference to the drawings. Fig. 7(a) shows an example of a pixel arranged in a light-emitting device. The pixel has sub-pixels 810 (light-emitting elements). The sub-pixels are divided into 810R, 810G, and 810B based on their light emission. The emitted colors may be distinguished by the wavelength of light emitted from the light-emitting layer, or the light emitted from the sub-pixels may be selectively transmitted or color-converted using a color filter or the like. Each sub-pixel has a reflective electrode 802 as a first electrode on an interlayer insulating layer 801, an insulating layer 803 covering the edge of the reflective electrode 802, an organic compound layer 804 covering the first electrode and the insulating layer, a transparent electrode 805 as a second electrode, a protective layer 806, and a color filter 807.

[0105] A transistor and a capacitor may be disposed below or inside the interlayer insulating layer 801. The transistor and the first electrode may be electrically connected via a contact hole (not shown) or the like.

[0106] The insulating layer 803 may also be called a bank or a pixel separation film. The insulating layer 803 covers the edges of the first electrodes and is disposed to surround the first electrodes. The portions of the first electrodes not covered by the insulating layer 803 come into contact with the organic compound layer 804 and become light-emitting regions.

[0107] The organic compound layer 804 includes a hole injection layer 841 , a hole transport layer 842 , a first light-emitting layer 843 , a second light-emitting layer 844 , and an electron transport layer 845 .

[0108] The second electrode may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

[0109] The protective layer 806 reduces the penetration of moisture into the organic compound layer. Although the protective layer is illustrated as a single layer, it may be a multi-layer structure. Each layer may be an inorganic compound layer and an organic compound layer.

[0110] The color filters 807 are divided into 807R, 807G, and 807B depending on their colors. The color filters may be formed on a planarization film (not shown). A resin protective layer (not shown) may be disposed on the color filters. The color filters may be formed on a protective layer 806. The color filters may be provided on an opposing substrate such as a glass substrate and then bonded thereto.

[0111] The display device 800 (light-emitting device) in FIG. 7(b) includes an organic light-emitting element 826 and a TFT 818 as an example of a transistor. A substrate 811 made of glass, silicon, or the like is provided with an insulating layer 812 on top of it. An active element such as the TFT 818 is disposed on the insulating layer, and a gate electrode 813, a gate insulating film 814, and a semiconductor layer 815 of the active element are disposed on top of the insulating layer. The TFT 818 also includes a semiconductor layer 815, a drain electrode 816, and a source electrode 817. An insulating film 819 is provided on top of the TFT 818. An anode 821 constituting the organic light-emitting element 826 and the source electrode 817 are connected via a contact hole 820 provided in the insulating film.

[0112] The electrical connection between the electrodes (anode, cathode) included in the organic light-emitting element 826 and the electrodes (source electrode, drain electrode) included in the TFT is not limited to the embodiment shown in Figure 7(b). In other words, it is sufficient that either the anode or the cathode is electrically connected to either the TFT source electrode or the drain electrode. TFT stands for thin film transistor.

[0113] 7(b), the organic compound layer 822 is illustrated as a single layer, but may be a multi-layer organic compound layer 822. A first protective layer 824 and a second protective layer 825 are provided on the cathode 823 to reduce deterioration of the organic light-emitting element.

[0114] In the display device 800 of FIG. 7(b), transistors are used as switching elements, but other switching elements may be used instead.

[0115] The transistors used in the display device 800 of Fig. 7(b) are not limited to transistors using single-crystal silicon wafers, but may also be thin-film transistors having an active layer on the insulating surface of a substrate. Examples of active layers include non-single-crystal silicon such as single-crystal silicon, amorphous silicon, and microcrystalline silicon, and non-single-crystal oxide semiconductors such as indium zinc oxide and indium gallium zinc oxide. Thin-film transistors are also called TFT elements.

[0116] The transistors included in the display device 800 of Figure 7(b) may be formed within a substrate such as a silicon substrate. Here, "formed within a substrate" means that the substrate itself, such as a silicon substrate, is processed to form the transistors. In other words, having a transistor within a substrate can be seen as the substrate and the transistor being formed integrally.

[0117] The organic light-emitting element according to this embodiment has its light emission brightness controlled by a TFT, which is an example of a switching element. By providing multiple organic light-emitting elements on a surface, an image can be displayed based on the respective light emission brightnesses. Here, the switching element according to this embodiment is not limited to a TFT, but may also be a transistor formed from low-temperature polysilicon or an active matrix driver formed on a substrate such as a silicon substrate. "On the substrate" can also be referred to as "inside the substrate." Whether to provide a transistor in the substrate or to use a TFT is determined by the size of the display unit. For example, if the size is about 0.5 inches, the organic light-emitting element may be provided on a silicon substrate.

[0118] 8(a) to 8(c) are schematic diagrams showing an example of an image forming apparatus using a light emitting device. The image forming apparatus 926 shown in Fig. 8(a) includes a photosensitive member 927, an exposure light source 928, a developing unit 931, a charging unit 930, a transfer unit 932, a transport unit 933 (the transport roller in the configuration of Fig. 8(a)), and a fixing unit 935.

[0119] Light 929 is emitted from an exposure light source 928, and an electrostatic latent image is formed on the surface of the photoconductor 927. A light emitting device can be used as this exposure light source 928. A developing unit 931 contains toner or the like as a developer and can function as a developing device that applies the developer to the exposed photoconductor 927. A charging unit 930 charges the photoconductor 927. A transfer unit 932 transfers the developed image to a recording medium 934. A transport unit 933 transports the recording medium 934. The recording medium 934 can be, for example, paper or film. A fixing unit 935 fixes the image formed on the recording medium.

[0120] 8(b) and 8(c) are schematic diagrams showing an exposure light source 928 in which a plurality of light-emitting units 936 are arranged along the longitudinal direction of a long substrate. A light-emitting device can be applied to the light-emitting units 936. That is, a plurality of pixels (light-emitting elements) are arranged along the longitudinal direction of the substrate. A direction 937 is parallel to the axis of the photosensitive member 927. This column direction is the same as the axial direction of the photosensitive member 927 when it rotates. This direction 937 can also be called the long axis direction of the photosensitive member 927.

[0121] FIG. 8(b) shows a configuration in which the light-emitting units 936 are arranged along the longitudinal direction of the photoconductor 927. FIG. 8(c) shows a modified configuration of the arrangement of the light-emitting units 936 shown in FIG. 8(b), in which the light-emitting units 936 are arranged alternately in the column direction in the first and second columns. The light-emitting units 936 are arranged at different positions in the row direction in the first and second columns. In the first column, multiple light-emitting units 936 are arranged at intervals, and in the second column, light-emitting units 936 are arranged at positions corresponding to the gaps between the light-emitting units 936 in the first column. Multiple light-emitting units 936 are also arranged at intervals in the row direction. The arrangement of the light-emitting units 936 shown in FIG. 8(c) can be described as, for example, a grid-like arrangement, a houndstooth arrangement, or a checkerboard pattern.

[0122] FIG. 9 is a schematic diagram illustrating an example of a display device using a light-emitting device. The display device 1000 may include a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. Flexible printed circuits FPCs 1002 and 1004 are connected to the touch panel 1003 and the display panel 1005. A control circuit including a logic circuit configured with transistors and the like is disposed on the circuit board 1007. The battery 1008 may not be disposed if the display device 1000 is not a portable device, and even if it is a portable device, it does not need to be disposed in this position. A light-emitting device can be applied to the display panel 1005. Pixels (light-emitting elements) disposed in the light-emitting device functioning as the display panel 1005 are connected to and operate with the control circuit disposed on the circuit board 1007.

[0123] The display device 1000 shown in FIG. 9 may be used as a display unit of a photoelectric conversion device (which may also be called an imaging device) that has an optical unit with multiple lenses and an imaging element that receives light that has passed through the optical unit and photoelectrically converts it into an electrical signal. The photoelectric conversion device may have a display unit that displays information acquired by the imaging element. The display unit may be a display unit exposed to the outside of the photoelectric conversion device or a display unit located within a viewfinder. The photoelectric conversion device may be a digital camera or a digital video camera.

[0124] FIG. 10 is a schematic diagram illustrating an example of a photoelectric conversion device using the light-emitting device of this embodiment. The photoelectric conversion device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The photoelectric conversion device 1100 may also be called an imaging device. A light-emitting device can be applied to the viewfinder 1101 or the rear display 1102, which are display units. In this case, the light-emitting device may display not only an image to be captured, but also environmental information, imaging instructions, and the like. The environmental information may include the intensity of external light, the direction of external light, the moving speed of the subject, the possibility that the subject will be blocked by an obstruction, and the like.

[0125] Since the timing suitable for capturing an image is often very short, it is better to display information as soon as possible. Therefore, a light-emitting device in which pixels (light-emitting elements) including light-emitting elements using organic light-emitting materials such as organic EL elements are arranged may be used in the viewfinder 1101 and the rear display 1102. This is because organic light-emitting materials have a fast response speed. Light-emitting devices using organic light-emitting materials are more suitable than liquid crystal display devices for these devices, which require high display speed.

[0126] The photoelectric conversion device 1100 has an optical section (not shown). The optical section has multiple lenses, which form an image on a photoelectric conversion element (not shown) housed in a housing 1104 that receives light that has passed through the optical section. The focus of the multiple lenses can be adjusted by adjusting their relative positions. This operation can also be performed automatically.

[0127] The light-emitting device may be applied to a display unit of an electronic device. In this case, the light-emitting device may have both a display function and an operation function. Examples of the portable terminal include a mobile phone such as a smartphone, a tablet, and a head-mounted display.

[0128] FIG. 11 is a schematic diagram showing an example of an electronic device using the light-emitting device of this embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The housing 1203 may have a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type reaction unit. The operation unit 1202 may be a biometric recognition unit that recognizes a fingerprint to perform unlocking, etc. A portable device having a communication unit can also be called a communication device. A light-emitting device can be applied to the display unit 1201.

[0129] 12(a) and 12(b) are schematic diagrams illustrating an example of a display device using a light-emitting device. FIG. 12(a) illustrates a display device such as a television monitor or a PC monitor. The display device 1300 has a frame 1301 and a display unit 1302. A light-emitting device can be applied to the display unit 1302. The display device 1300 may have a base 1303 that supports the frame 1301 and the display unit 1302. The base 1303 is not limited to the form shown in FIG. 12(a). For example, the bottom edge of the frame 1301 may also serve as the base 1303. The frame 1301 and the display unit 1302 may be curved. The radius of curvature may be 5000 mm or more and 6000 mm or less.

[0130] FIG. 12(b) is a schematic diagram showing another example of a display device using a light-emitting device. The display device 1310 in FIG. 12(b) is configured to be bendable and is a so-called foldable display device. The display device 1310 has a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. A light-emitting device can be applied to the first display unit 1311 and the second display unit 1312. The first display unit 1311 and the second display unit 1312 may be a single display unit without any joints. The first display unit 1311 and the second display unit 1312 can be separated by the bending point. The first display unit 1311 and the second display unit 1312 may display different images, or the first display unit and the second display unit may display a single image.

[0131] FIG. 13 is a schematic diagram showing an example of a lighting device using a light-emitting device. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusion unit 1405. A light-emitting device can be applied to the light source 1402. The optical film 1404 may be a filter that improves the color rendering of the light source. The light diffusion unit 1405 can effectively diffuse light from the light source, such as for lighting, and deliver the light over a wide area. If necessary, a cover may be provided on the outermost part. The lighting device 1400 may include both the optical film 1404 and the light diffusion unit 1405, or only one of them.

[0132] The lighting device 1400 is, for example, a device that illuminates a room. The lighting device 1400 may emit white, daylight white, or any other color from blue to red. It may have a dimming circuit that adjusts the light intensity. The lighting device 1400 may have a power supply circuit connected to a light-emitting device that functions as the light source 1402. The power supply circuit is a circuit that converts AC voltage into DC voltage. White has a color temperature of 4200K, and daylight white has a color temperature of 5000K. The lighting device 1400 may also have a color filter. The lighting device 1400 may also have a heat sink. The heat sink dissipates heat from within the device to the outside, and examples of the heat sink include metal with a high specific heat, liquid silicon, etc.

[0133] FIG. 14 is a schematic diagram of an automobile having a tail lamp, which is an example of a vehicle lamp using a light-emitting device. The automobile 1500 has a tail lamp 1501, and may be configured to turn on the tail lamp 1501 when braking or the like is performed. The light-emitting device may be used as a headlamp as a vehicle lamp. An automobile is an example of a mobile body, and the mobile body may be a ship, a drone, an aircraft, a railroad vehicle, an industrial robot, or the like. The mobile body may have a body and a lamp attached thereto. The lamp may indicate the current location of the body.

[0134] A light emitting device can be applied to tail lamp 1501. Tail lamp 1501 may have a protective member that protects the light emitting device functioning as tail lamp 1501. The protective member may be made of any material as long as it has a certain degree of strength and is transparent, but may be made of polycarbonate or the like. The protective member may also be made by mixing polycarbonate with a furandicarboxylic acid derivative, an acrylonitrile derivative, or the like.

[0135] The automobile 1500 may have a body 1503 and a window 1502 attached to the body. The window may be a window for checking the front and rear of the automobile, or may be a transparent display such as a head-up display. A light-emitting device may be used in the transparent display. In this case, the constituent materials of the electrodes and the like of the light-emitting device are made of transparent materials.

[0136] 15(a) and 15(b), further application examples of the light-emitting device will be described. The light-emitting device can be applied to systems that can be worn as wearable devices, such as smart glasses, head-mounted displays (HMDs), and smart contact lenses. An image capturing and displaying device used in such application examples has an image capturing device capable of photoelectrically converting visible light and a light-emitting device capable of emitting visible light.

[0137] 15(a) illustrates glasses 1600 (smart glasses) according to one application example. An imaging device 1602 such as a CMOS sensor or SPAD is provided on the front side of a lens 1601 of the glasses 1600. In addition, a light emitting device is provided on the back side of the lens 1601.

[0138] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the image capture device 1602 and the light emitting device. The control device 1603 also controls the operations of the image capture device 1602 and the light emitting device. The lens 1601 is formed with an optical system for focusing light onto the image capture device 1602.

[0139] FIG. 15(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 include a control device 1612, which is equipped with an imaging device and a light-emitting device equivalent to the imaging device 1602. A lens 1611 includes an optical system for projecting light emitted from the imaging device and the light-emitting device within the control device 1612, and an image is projected onto the lens 1611. The control device 1612 functions as a power source for supplying power to the imaging device and the light-emitting device and controls the operation of the imaging device and the light-emitting device. The control device 1612 may also include a gaze detection unit for detecting the gaze of the wearer. Infrared light may be used for gaze detection. The infrared light-emitting unit emits infrared light toward the eyeball of a user gazing at a displayed image. An imaging unit with a light-receiving element detects the reflected light of the emitted infrared light from the eyeball, thereby obtaining an image of the eyeball. A reduction unit for reducing light from the infrared light-emitting unit to the display unit in a planar view reduces degradation of image quality.

[0140] The gaze of the user relative to the displayed image is detected from an image of the eyeball captured using infrared light. Any known method can be used for gaze detection using an image of the eyeball. As an example, a gaze detection method based on a Purkinje image formed by reflection of irradiated light on the cornea can be used.

[0141] More specifically, gaze detection processing is performed based on the pupil-corneal reflex method, which calculates a gaze vector representing the direction (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the captured image of the eyeball, thereby detecting the user's gaze.

[0142] The light-emitting device may have an imaging device with a light-receiving element and control the display image based on user line-of-sight information from the imaging device. Specifically, the light-emitting device determines a first field of view area where the user gazes and a second field of view area other than the first field of view area based on the line-of-sight information. The first field of view area and the second field of view area may be determined by a control device of the light-emitting device, or may be determined by an external control device and received. In the display area of ​​the light-emitting device, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area may be lower than that of the first field of view area.

[0143] The display area includes a first display area and a second display area different from the first display area, and a high-priority area is determined from the first display area and the second display area based on line-of-sight information. The first display area and the second display area may be determined by a control device of the light-emitting device, or may be determined by an external control device and received. The resolution of the high-priority area may be controlled to be higher than the resolution of areas other than the high-priority area. In other words, the resolution of an area with a relatively low priority may be lowered.

[0144] Note that AI may be used to determine the first field of view area and areas with high priority. The AI ​​may be a model configured to estimate the angle of gaze and the distance to an object in the line of sight from the image of the eyeball, using as training data an image of the eyeball and the direction in which the eyeball in the image was actually looking. The AI ​​program may be included in the light-emitting device, the imaging device, or an external device. If included in an external device, it is transmitted to the light-emitting device via communication.

[0145] When display control is performed based on visual recognition detection, the smart glasses can be applied to smart glasses that further include an imaging device for capturing images of the outside world. The smart glasses can display captured outside information in real time.

[0146] The disclosure of the present specification includes the following deposition mask, deposition mask manufacturing method, and light-emitting device manufacturing method.

[0147] (Item 1) A deposition mask having a plurality of openings formed in a substrate, a material layer having a different material from the substrate is disposed on an inner wall of the substrate facing each of the plurality of openings; The deposition mask is characterized in that the material layer has an uneven shape in a portion facing the inner wall.

[0148] (Item 2) the deposition mask has a first main surface facing a deposition target substrate and a second main surface opposite to the first main surface, 2. The deposition mask according to item 1, wherein the material layer covers at least a part of the second main surface.

[0149] (Item 3) 3. The deposition mask according to item 2, wherein the material layer does not cover the first main surface.

[0150] (Item 4) 4. The deposition mask according to any one of items 1 to 3, wherein the ratio of the depth to the width of the recesses of the uneven shape is 1 or more.

[0151] (Item 5) the material layer includes a first region and a second region disposed between the first region and the inner wall; 5. The deposition mask according to any one of items 1 to 4, wherein the first region and the second region have different densities.

[0152] (Item 6) 6. The deposition mask according to item 5, wherein the density of the second region is greater than the density of the first region.

[0153] (Item 7) 7. The deposition mask according to any one of items 1 to 6, wherein the material layer contains aluminum oxide crystals.

[0154] (Item 8) 8. The deposition mask according to any one of items 1 to 7, wherein the material layer has a higher etching rate in a solution containing hydrochloric acid than the substrate.

[0155] (Item 9) 7. The deposition mask according to any one of items 1 to 6, wherein the material layer contains at least one of aluminum oxide, titanium oxide, and an organic polymer.

[0156] (Item 10) 10. The deposition mask according to any one of items 1 to 9, wherein the substrate contains silicon.

[0157] (Item 11) A method for manufacturing a deposition mask, comprising: providing a substrate having a plurality of openings; forming a material layer having a different material from the substrate on an inner wall of the substrate facing each of the plurality of openings; forming a concave-convex shape on a portion of the material layer facing the inner wall; A manufacturing method comprising:

[0158] (Item 12) Item 12. The manufacturing method according to item 11, wherein the material layer is formed using atomic layer deposition.

[0159] (Item 13) 13. The manufacturing method according to item 11 or 12, wherein the preparing step includes a step of peeling the material layer from a used deposition mask.

[0160] (Item 14) Item 14. The manufacturing method according to item 13, wherein the deposition mask from which the material layer is peeled off is a deposition mask that has been used for depositing a deposition material.

[0161] (Item 15) 15. The manufacturing method according to any one of items 11 to 14, wherein the material layer comprises aluminum oxide.

[0162] (Item 16) the material layer comprises aluminum oxide; Item 14. The manufacturing method according to item 13, wherein the peeling step includes immersing the deposition mask in a solution containing hydrochloric acid.

[0163] (Item 17) Item 17. The manufacturing method according to item 16, wherein the deposition mask immersed in the solution containing hydrochloric acid is a deposition mask that has been used to deposit a deposition material.

[0164] (Item 18) 18. The manufacturing method according to any one of items 15 to 17, wherein the step of forming the uneven shape includes immersing the material layer in warm water.

[0165] (Item 19) Item 19. The method according to item 18, wherein the temperature of the hot water is 70°C or higher and 100°C or lower.

[0166] (Item 18) A method for manufacturing a light-emitting device in which a plurality of pixels are arranged, each pixel including an organic layer including a light-emitting layer, comprising: forming the organic layer using a deposition mask having a plurality of openings formed in a substrate; the deposition mask includes a material layer having a different material from the substrate, the material layer being disposed on an inner wall of the substrate facing each of the plurality of openings; The manufacturing method is characterized in that the material layer has an uneven shape in a portion facing the inner wall.

[0167] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0168] 101: deposition mask, 104: material layer, 105: opening, 106: inner wall, 121: substrate

Claims

1. A deposition mask having a plurality of openings formed in a substrate, a material layer having a different material from the substrate is disposed on an inner wall of the substrate facing each of the plurality of openings; The deposition mask is characterized in that the material layer has an uneven shape in a portion facing the inner wall.

2. the deposition mask includes a first main surface facing a deposition target substrate and a second main surface opposite to the first main surface, The deposition mask according to claim 1 , wherein the material layer covers at least a part of the second main surface.

3. The deposition mask according to claim 2 , wherein the material layer does not cover the first main surface.

4. 2. The deposition mask according to claim 1, wherein the ratio of the depth to the width of the recesses of the uneven shape is 1 or more.

5. the material layer includes a first region and a second region disposed between the first region and the inner wall; The deposition mask according to claim 1 , wherein the first region and the second region have different densities.

6. 6. The deposition mask according to claim 5, wherein the density of the second region is higher than the density of the first region.

7. 2. The deposition mask according to claim 1, wherein the material layer contains aluminum oxide crystals.

8. 2. The deposition mask according to claim 1, wherein the material layer has a higher etching rate with respect to a solution containing hydrochloric acid than the substrate.

9. 2. The deposition mask according to claim 1, wherein the material layer includes at least one of aluminum oxide, titanium oxide, and an organic polymer.

10. The deposition mask according to claim 1 , wherein the substrate contains silicon.

11. A method for manufacturing a deposition mask, comprising: providing a substrate having a plurality of openings; forming a material layer having a different material from the substrate on an inner wall of the substrate facing each of the plurality of openings; forming a concave-convex shape on a portion of the material layer facing the inner wall; A manufacturing method comprising:

12. The method of claim 11 , wherein the material layer is formed using atomic layer deposition.

13. The manufacturing method according to claim 11 , wherein the preparing step includes a step of peeling the material layer from a used deposition mask.

14. The manufacturing method according to claim 13 , wherein the deposition mask from which the material layer is peeled off is a deposition mask that has been used for depositing a deposition material.

15. The method of claim 11 , wherein the layer of material comprises aluminum oxide.

16. the material layer comprises aluminum oxide; The manufacturing method according to claim 13 , wherein the removing step includes immersing the deposition mask in a solution containing hydrochloric acid.

17. 17. The manufacturing method according to claim 16, wherein the deposition mask immersed in the solution containing hydrochloric acid is a deposition mask that has been used for depositing a deposition material.

18. The method of claim 15, wherein the step of forming the irregularities includes immersing the material layer in warm water.

19. 19. The method according to claim 18, wherein the temperature of the hot water is 70°C or higher and 100°C or lower.

20. A method for manufacturing a light-emitting device in which a plurality of pixels are arranged, each pixel including an organic layer including a light-emitting layer, comprising: forming the organic layer using a deposition mask having a plurality of openings formed in a substrate; the deposition mask includes a material layer having a different material from the substrate, the material layer being disposed on an inner wall of the substrate facing each of the plurality of openings; The manufacturing method is characterized in that the material layer has an uneven shape in a portion facing the inner wall.

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