TWI692896B - Method of manufacturing organic light-emitting diode and organic light-emitting diode - Google Patents

Abstract

The present invention relates to a metallic mold including a flat surface and a plurality of protrusions on a main surface, wherein the average pitch between the plurality of protrusions is 50nm to 5μm, the average aspect ratio of the plurality of the protrusions is 0.01 to 1, 80% or more of the plurality of protrusions have a predetermined curved surface, and in the predetermined curved surface, when a first point is arbitrarily set and a second point is set at a position equal to a distance 1/10 of the average pitch away from the first point, the inclined angle of a second tangential plane which contacts the second point with respect to the first tangential plane which contacts the first position is 60° or less.

Description

Manufacturing method of organic light-emitting diode and organic light-emitting diode

The invention relates to a mold, a method for manufacturing an organic light-emitting diode, and an organic light-emitting diode. This case claims priority based on Japanese Patent Application No. 2015-178324 filed in Japan on September 10, 2015, and the contents are cited here.

The organic light-emitting diode system uses organic electroluminescent light-emitting elements. Organic light-emitting diodes generally have a structure in which an anode and a cathode are provided on both surfaces of an organic semiconductor layer including a light-emitting layer containing an organic light-emitting material. In addition to the light-emitting layer, the organic semiconductor layer has an electron injection layer, an electron transport layer, a hole transport layer, a hole injection layer, etc. as needed. Organic light emitting diodes have the advantages of less viewing angle dependence, less power consumption, and extremely thin ones.

On the other hand, the light extraction efficiency of the organic light emitting diode is not necessarily sufficient. The light extraction efficiency is the ratio of the light energy released into the atmosphere from the light extraction surface (for example, the base surface in the case of a bottom-emission type) relative to the light energy generated in the light-emitting layer.

As one of the main reasons for lowering the light extraction efficiency, there is the effect of surface plasmons. In organic light-emitting diodes, the distance between the light-emitting layer and the metal cathode is relatively short. Therefore, part of the near-field light generated in the light-emitting layer is converted into surface plasmon on the surface of the cathode and disappears, and the light extraction efficiency of the organic light-emitting diode is reduced. Light extraction efficiency is an index that affects the brightness of displays, lighting, etc. equipped with organic light-emitting diodes, and various methods for improvement are being studied. In order to improve light extraction efficiency, Patent Document 1 discloses a structure in which a two-dimensional lattice structure of convex portions or concave portions is provided on the surface of a metal layer (cathode). The two-dimensional lattice structure on the surface of the metal layer converts the energy of the surface plasmons into light, and takes the converted light out of the device. In Patent Document 1, the two-dimensional lattice structure on the surface of the metal layer can be obtained by reflecting the two-dimensional lattice structure provided on the substrate. Specifically, since the first electrode on the base provided with the two-dimensional lattice structure, the organic semiconductor layer including the light-emitting layer, and the second electrode are reflected on the surface of the second electrode on the light-emitting layer side, the second equivalent to the base Dimensional lattice structure. Generally, the organic semiconductor layer and the first and second electrodes are formed by a vacuum film formation method using sputtering or vapor deposition. On the other hand, Patent Document 2 discloses that an organic semiconductor layer in an organic thin-film solar cell is formed by a coating method such as a spin coating method, an inkjet method, and a slit coating method. The organic thin-film solar cell has the same structure as the organic light-emitting diode, and the organic semiconductor layer of the organic light-emitting diode can also be formed by a coating method. [Prior Art Literature] [Patent Literature] [Patent Literature 1] International Publication No. 2012/60404 [Patent Literature 2] International Publication No. 2014/208713

[Problems to be Solved by the Invention] However, for example, the method of processing a two-dimensional lattice structure on a substrate like the method described in Patent Document 1 has a problem that the processing cost of the substrate becomes high. In addition, there is a problem that when a substrate is processed to produce a two-dimensional lattice structure, the organic semiconductor layer formed on the substrate cannot be formed by the coating method described in Patent Document 2. Since the coating method uses liquid phase materials during coating, it is easy to fill the uneven shape (two-dimensional lattice structure). Therefore, compared with the vacuum film forming method, the reflectivity of the uneven shape on the surface of the substrate becomes lower on the surface of the metal layer. If the reflectivity of the shape is low, it is difficult to provide the second electrode with the desired shape required for taking out surface plasmons. On the other hand, forming an organic semiconductor layer by coating has advantages such as a reduction in manufacturing cost due to the simplification of manufacturing equipment and an increase in output due to shortening the time for vacuuming and the like. Therefore, there is a strong demand to form an organic semiconductor layer using a coating method. Therefore, the inventors of the present invention have adopted a method of manufacturing an organic light-emitting diode by sequentially performing a coating step, a stamper step for forming an uneven shape, and a vacuum film-forming step. In this method, first, in the coating step, at least a part of the organic semiconductor layer is formed by the coating method. Then, the mold having the opposite shape to the desired unevenness is pressed against the outermost surface of the coating layer obtained in the coating step, and the desired unevenness is formed on the outermost layer of the coating layer. Finally, the remaining layer not formed in the coating step is formed by the vacuum film forming method. This method does not need to process the substrate, so it has the advantage of reducing the processing cost of the substrate. Since it can reduce the number of layers produced by vacuum film formation, it has the advantage of increasing the production output. Because the vacuum is used after the formation of the uneven shape The film forming method has the advantage that the desired uneven shape can be reflected in the second electrode. However, as a result of further research by the inventors and others, the following problem was found: the organic light-emitting diode produced by combining the coating step, the compression molding step, and the vacuum film-forming step cannot obtain sufficient luminous intensity compared with the luminous intensity assumed . The present invention has been completed in view of the above circumstances. An object of the present invention is to provide a mold for producing an organic light-emitting diode that exhibits sufficient light-emitting characteristics even when a method combining a coating step, a stamping step, and a vacuum film-forming step is used. [Technical Means for Solving the Problems] The inventors of the present invention have made intensive studies to solve the above-mentioned problems. As a result, it was found that by making the shape of the mold a specific shape, even in the case of combining the coating step, the stamping step, and the vacuum film-forming step to produce an organic light-emitting diode, the organic light-emitting diode can Show sufficient luminous properties. The present invention includes the following inventions. (1) The mold of one aspect of the present invention has a flat surface and a plurality of convex portions on the main surface. The average pitch of the plurality of convex portions is 50 nm to 5 μm, and the average aspect ratio of the plurality of convex portions is 0.01 ～1, 80% or more of the plurality of convex portions have a specific curved surface, the specific curved surface is set at any point of the specific curved surface as the first point, and will deviate from the first point only by the above When the point of 1/10 of the average pitch is set as the second point, the inclination angle of the second tangent plane in contact with the second point with respect to the first tangent plane in contact with the first point is within 60°. (2) In the mold described in (1) above, the area ratio of the flat surface of the main surface may be 5 to 50%. (3) In the mold described in any one of (1) or (2) above, the flat surface and the convex portion having the specific curved surface may be connected in such a manner as to satisfy the conditions of the specific curved surface . (4) In the mold described in any one of (1) to (3) above, the specific curved surface constituting the plurality of convex portions may have at least one recurved portion, and the recurved portion The closest distance from the first curved portion closest to the flat surface to the flat surface is 1/10 or more of the average pitch of the plurality of convex portions. (5) In the mold described in any one of (1) to (4) above, a honeycomb lattice may be formed for the plurality of convex portions, and in a plan view from a direction perpendicular to the flat surface, the plurality of The top of each convex portion is located at the vertex of the hexagon that constitutes the honeycomb lattice. (6) In the mold described in (5) above, the convex portion located at the vertex of the hexagon may have a ridge portion between the convex portion located at the vertex adjacent to the hexagon, and the ridge portion At least a portion exists on the flat surface side of the convex portion connecting the ridge portion. (7) In the mold described in (6) above, the height of the portion of the ridge portion closest to the flat surface from the flat surface may be the height of the convex portion connecting the ridge portion from the flat surface It is 50%～90%. (8) The method for manufacturing an organic light-emitting diode according to one aspect of the present invention is to form a substrate with an electrode having a transparent first electrode on the substrate through a coating step and a subsequent vacuum film-forming step An organic semiconductor layer including a light-emitting layer and a second electrode are formed on the surface with the first electrode, and between the coating step and the vacuum film-forming step, any of the above (1) to (7) The die described in the item is pressed against the outermost surface of the coating layer formed in the above coating step, and the step of forming the inverted shape of the main surface of the mold on the outermost surface of the coating layer . (9) An organic light-emitting diode according to an aspect of the present invention has a substrate, a transparent first electrode, an organic semiconductor layer including a light-emitting layer, and a second electrode, the second electrode on the side of the organic semiconductor layer The surface has a flat surface, and a plurality of convex portions protruding from the flat surface toward the substrate, the average pitch of the plurality of convex portions is 50 nm to 5 μm, and the average aspect ratio of the plurality of convex portions is 0.01 to 1. More than 80% of the plurality of convex portions have a specific curved surface, the specific curved surface is set at any point of the specific curved surface as the first point, and will be from the first point toward the center point of the convex portion When only a point deviating from 1/10 of the average pitch is set as the second point, the inclination angle of the second tangent plane that is in contact with the second point with respect to the first tangent plane that is in contact with the first point is 60° Within. (10) In the organic light-emitting diode described in (9) above, the area ratio of the flat surface of the surface of the second electrode on the side of the organic semiconductor layer may be 5 to 50%. [Effects of the invention] Even if the mold of one aspect of the present invention is combined with a coating step, a compression molding step, and a vacuum film-forming step to produce an organic light-emitting diode, the organic light-emitting diode can exhibit sufficient Luminous properties. The organic light-emitting diode according to one aspect of the present invention has the desired light-emitting characteristics, and the generated surface plasmons can be efficiently taken out. The method for manufacturing an organic light-emitting diode according to one aspect of the present invention can produce an organic light-emitting diode that can efficiently extract surface plasmons at low cost.

二唑(BND)、2-(4-第三丁基苯基)-5-(4-聯苯)-1,3,4-

二唑(PBD)等

二唑系化合物、三(8-喹啉根基)鋁(Alq)等金屬錯合物系化合物等。 包含發光層133之有機半導體層之整體之厚度通常為30～500 nm。 第1電極120使用透過可見光之透明導電體。 構成第1電極120之透明導電體並不特別限定，作為透明導電材料可使用公知者。例如，可列舉氧化銦錫(Indium Tin Oxide(ITO))、氧化銦鋅(Indium Zinc Oxide(IZO))、氧化鋅(Zinc Oxide(ZnO))、氧化鋅錫(Zinc Tin Oxide(ZTO))等。第1電極120之厚度通常為50～500 nm。 基體110使用透過可見光之透明體。作為構成基體110之材質，既可為無機材料亦可為有機材料，亦可為其等之組合。作為無機材料，例如可列舉石英玻璃、無鹼玻璃、白板玻璃等各種玻璃、雲母等透明無機礦物等。作為有機材料，可列舉環烯系膜、聚酯系膜等樹脂膜、於該樹脂膜中混入有纖維素奈米纖維等微細纖維而成之纖維強化塑膠素材等。 雖亦根據用途，但一般而言基體110使用可見光透過率較高者。使用如下者，即，透過率於可見光之範圍(波長380 nm～800 nm)未於光譜賦予偏倚而為透過率70%以上，較佳為80%以上，更佳為90%以上。 構成有機發光二極體100之各層之厚度可藉由光譜式橢圓儀、接觸式階差計、AFM等而測定。 「有機發光二極體之製造方法」 本發明之一態樣之有機發光二極體之製造方法係於在基體上具有透明之第1電極之帶電極之基體的形成有第1電極之面，藉由塗佈步驟與其後之真空成膜步驟而形成包含發光層之有機半導體層與第2電極的有機發光二極體之製造方法。於塗佈步驟與真空成膜步驟之間，具有將上述模具壓抵於塗佈步驟所形成之塗佈層之最外表面，而於塗佈層之最外表面形成模具之主面之形狀之反轉形狀的壓模步驟。 ＜帶電極之基體的準備步驟＞ 帶電極之基體係於透明之基體上形成透明之第1電極。基體及第1電極可使用上述者。 於基體上形成第1電極之方法可使用公知之方法。例如，可將ITO等透明電極用材料藉由濺鍍而形成於基體上。又，亦可購入市售之帶電極之基體。 ＜塗佈步驟＞ 於塗佈步驟中，藉由塗佈而形成構成有機半導體層之層中之一部分層、或所有層。一般而言，於塗佈步驟中必須以不侵入至前步驟為止已經成膜之各層之方式選擇塗佈液之溶劑，故而藉由塗佈而成膜之層之數量越增加越難以選擇適當之溶劑。因此，於塗佈步驟中，較佳為形成至構成有機半導體層之層中之發光層為止。 塗佈法可使用公知之方法，例如可使用旋轉塗佈、棒式塗佈、狹縫式塗佈、模嘴塗佈、噴塗、噴墨法等。塗佈法無須使積層時之環境為真空，不需要大規模之設備。又，由於不需要抽真空等時間，故而可使製造有機發光二極體之產出量提高。 ＜壓模步驟＞ 壓模步驟係藉由所謂壓印法而形成凹凸形狀之方法。若將模具壓抵於塗佈步驟中所形成之塗佈層，則構成塗佈層之塗佈液沿著模具之形狀而追隨。塗佈液由於具有可維持形狀之程度之黏度，故而於將模具卸除之後亦維持其形狀。 又，即便於塗佈液乾燥、蒸發之後，於形成成膜層之材料存在玻璃轉移點之情形時，亦能夠藉由於將成膜層加熱至玻璃轉移點以上之狀態下壓抵模具而賦予形狀。 於壓模步驟中，將本發明之一態樣之模具壓抵於在塗佈步驟所形成之塗佈層之最外層。所謂最外層係指塗佈步驟中所形成之最後之層，且係於塗佈步驟結束之階段距基體最遠之層。例如，於利用塗佈形成至圖12之發光層133為止之情形時，將模具壓抵於發光層133之第2電極140側之面而轉印模具之反轉形狀。 如上所述，本發明之一態樣之模具具有複數個凸部及平坦面，該等複數個凸部具有特定之彎曲面。因此，於將模具壓抵於發光層133時，施加至發光層133之力沿著特定之彎曲面而分散。其結果，可避免發光層133之層厚變得極薄之情況或發光層133被切斷之情況等。 ＜真空成膜步驟＞ 於真空成膜步驟中，藉由真空成膜法而形成構成有機半導體層之層中未於塗佈步驟形成之層及第2電極。 作為真空成膜法，可使用真空蒸鍍法、濺鍍法、CVD(chemical vapor deposition，化學氣相成長法)等。為了減少對有機層之損傷，較佳為使用真空蒸鍍法作為真空成膜法。 真空成膜法與塗佈法比較反映基底之形狀之反映性較高。因此，於壓模步驟中形成於塗佈層之最外層之凸部與平坦面之形狀亦反映於積層於塗佈層之最外層上部之層。 於藉由壓抵模具而形成於塗佈層之最外層之凹部中，較佳為凹部與平坦面利用特定之彎曲面而連結。即，較佳為凹部與平坦面之交界平緩。可更加抑制藉由真空成膜而形成之層之層厚不均勻。 藉由於塗佈層之最外層形成上述之凹部與平坦面，而於第2電極之發光層側之面如圖12所示形成與塗佈層之最外層反轉之形狀。該形狀為反映壓模步驟中壓抵之模具之形狀之形狀。 於本發明之一態樣之有機發光二極體之製造方法中，由於具有使用具有特定形狀之模具之壓模步驟，故而可於第2電極之發光層側簡單地形成所期望之凹凸。利用該方法製造之有機發光二極體可取出表面電漿子，從而可獲得較高之發光特性。Hereinafter, each structure will be described using drawings. The drawings used in the following descriptions may be enlarged for the sake of easy understanding of the features and for convenience, and the size ratios of the components may not be the same as the actual conditions. The materials, dimensions, etc. exemplified in the following description are examples, and the present invention is not limited to these and the like, and can be implemented with appropriate changes without changing the scope of the gist thereof. "Mold" FIG. 1 is a perspective view schematically showing a mold of one aspect of the present invention. In the mold 10 of one aspect of the present invention, a plurality of flat surfaces 1a to 1n and a plurality of convex portions 2a to 2n are provided on the main surface 10A. The plurality of flat surfaces 1a to 1n are arranged in an area surrounded by the most adjacent convex portions among the plurality of convex portions 2a to 2n. In FIG. 1, if the center points of the most adjacent convex portions are connected, a hexagon viewed from above is depicted, and a flat surface is provided in the central area. A plurality of convex portions 2a to 2n are connected in part. FIG. 2 is a cross-sectional view taken along the plane connecting the center point of the convex portion of the mold of one aspect of the present invention and the center point of the flat surface. The cross section shown in FIG. 2 is obtained in the form of an AFM (Atomic Force Microscopy, Atomic Force Microscope) image or a microscope image obtained by observing and cutting the sample with an electron microscope. The cross section of the AFM image is an AFM image obtained by photographing a square area 30 to 40 times the average pitch P of the convex portions 2a to 2n, and the central point 2An of the convex portion 2n and the central point 1An of the flat surface 1n are taken out The cross-sectional profile information is obtained. The cross-section is obtained by cutting the mold 10 through FIB (Focused Ion Beam, focused ion beam) or the like through the center point 2An of the convex portion 2n. The microscope image of the section is obtained by observing the section with an optical microscope. When there is a possibility that the cross-sectional shape of the mold may be deformed by cutting, it is preferable to cover the surface of the convex portion with a material that can withstand cutting or to embed the convex portion with resin or the like for cutting. In the case where any one of the cross section measured by the AFM image and the cross section observed by the microscope image is available, the cross section measured by the AFM image is preferred. The reason is that the cross-section measured by the AFM image can easily obtain the measurement surface of the specific cut surface, and it is easy to confirm the cross-sectional shape. In the case where the convex portions 2a to 2n are regularly arranged, it is preferable to set the cutting direction used to obtain the cross section as the direction along the arrangement direction of the convex portions 2a to 2n. The center points 2Aa to 2An of the convex portions 2a to 2n are set based on the measurement results of AFM. Specifically, a plurality of contour lines are drawn for each of the convex portions 2a to 2n parallel to the reference plane at intervals of 20 nm, and the center of gravity of each contour line (a point determined by the x coordinate and the y coordinate) is obtained. The average position of the center of gravity points (position value determined by the average value of each x coordinate and the average value of y coordinate) is set as the center points 2Aa to 2An of the convex portions 2a to 2n. The reference plane is a measurement plane after the slope is corrected by the image information with the slope measured by AFM. The center points 1Aa to 1An of the flat surfaces 1a to 1n are set based on the measurement results of AFM. Specifically, each of the plurality of flat surfaces 1a to 1n is provided with an inscribed circle inscribed in plan view. Let the center of the inscribed circle be the center points 1Aa to 1An of the flat surfaces 1a to 1n. The convex portions 2a to 2n are portions that protrude from the flat surfaces 1a to 1n. The flat surfaces 1a to 1n refer to a region whose slope is within ±5゜ with respect to a plane parallel to the reference plane of the AFM by the center of gravity of the region connecting the most adjacent convex portions. The convex portions 2a to 2n are two-dimensionally arranged on one surface of the mold 10. The so-called "two-dimensional arrangement" refers to a state in which a plurality of convex portions are arranged on the same plane. The two-dimensional structure in which a plurality of convex portions are two-dimensionally arranged may be periodic or aperiodic. The mold 10 can be preferably used when a metal-containing electrode of an organic light-emitting diode is used to make an uneven shape. The uneven shape helps to remove the surface plasmons generated on the electrode surface. When the organic light emitting diode manufactured by the mold 10 emits light in a narrower frequency band, the two-dimensional arrangement of the plurality of convex portions is preferably periodic. As a preferable specific example of the periodic two-dimensional structure, the alignment direction of the straight line connecting adjacent convex portions is two directions and the intersection angle is 90° (square lattice), and the adjacent convex portion The alignment direction of the connected straight lines is 3 directions and the crossing angle is 120° (hexagonal lattice, honeycomb lattice), etc. The so-called "positional relationship where the crossing angle is 120°" specifically refers to a relationship that satisfies the following conditions. First, a line segment L1 having a length equal to the average pitch P is drawn from one center point 2Aa to the direction of the adjacent center point 2Ab. Then, a line segment L2 having a length equal to the average pitch P is drawn from the center point 2Aa in the direction of 120° with respect to the line segment L1. If the center point adjacent to the center point 2Aa is within 15% of the average pitch P from the end point of each line segment L1 opposite to the center point 2Aa, the intersection angle is at a positional relationship of 120°. The positional relationship where the crossing angle is 90 degrees is defined by replacing the above description of "120°" with "90°". If the convex portions 2a to 2n are periodically arranged in a manner satisfying the above relationship, the period of the arrangement of the convex portions 2a to 2n resonates with the period of the surface plasmon, and the extraction efficiency of light in a specific frequency band is improved. In addition, when the convex portions 2a to 2n are arranged in a honeycomb lattice shape, the strength of the mold 10 increases, and the durability during repeated use is particularly improved. In other words, the honeycomb lattice shape is a relationship in which the tops of the plurality of convex portions 2a to 2n are located at the apexes of the hexagon when viewed from above in a direction perpendicular to the flat surfaces 1a to 1n. On the other hand, when the organic light-emitting diode manufactured using the mold 10 emits light of a wider frequency band or lights of plural frequency bands different from each other, the two-dimensionality of the plural convex portions 2a to 2n is preferable The configuration is acyclic. The so-called "aperiodic arrangement" refers to a state in which the interval between the centers of the convex portions 2a to 2n and the arrangement direction are not fixed. Here, the average pitch P is the distance between adjacent convex portions, and specifically, it can be obtained as follows. Here, the adjacent convex portion refers to the case where the convex portion is adjacent without the flat surface in FIG. 1. First, an AFM image is obtained for a randomly selected area in the main surface 10A of the mold 10 for a square area whose side is 30 to 40 times the average pitch P. For example, in the case where the design spacing is about 300 nm, an image of an area of 9 μm×9 μm to 12 μm×12 μm is obtained. Further, the distance between adjacent parts of the convex portions in the obtained area is measured, and the measured distance between adjacent parts is averaged to obtain the average pitch P _{1 in} the region. Randomly select a total of 25 or more areas of the same area to perform this process in the same way, and find the average pitch P ₁ to P _{25 in} each area. The average value of the average pitches P ₁ to P ₂₅ in the 25 or more regions thus obtained is the average pitch P. At this time, the regions are preferably selected at least 1 mm apart from each other, and more preferably selected from 5 mm to 1 cm apart. The average pitch P of the convex portions 2a to 2n is 50 nm to 5 μm, preferably 50 nm to 500 nm. If the average pitch of the convex portions 2a to 2n is within this range, in the organic light-emitting diode manufactured using the mold 10, surface plasmons can be efficiently extracted from the metal electrode. The convex portions 2a to 2n are formed of Ca to Cn in a periodic structure in each region. As a whole in the macro, the Ca to Cn of each area can also be a non-periodic structure. Each of the regions Ca to Cn shown in FIG. 3 is a region in which the center point of each convex portion has a cross angle of 120° with respect to the center point of the flat surface. In FIG. 3, for the sake of convenience, the position of the center point of each convex portion 2a to 2n is represented by a circle u with the center point as the center. The most frequent area Q of each area Ca to Cn (the most frequent value of each area) is preferably in the following range. When the average pitch P is less than 500 nm, the most frequent area Q in the AFM image measurement range of 10 μm×10 μm is preferably 0.026 μm ² to 6.5 μm ² . When the average pitch P is 500 nm or more and less than 1 μm, the most frequent area Q in the AFM image measurement range of 10 μm×10 μm is preferably 0.65 μm ² to 26 μm ² . When the average pitch P is 1 μm or more, the most frequent area Q in the AFM image measurement range of 50 μm×50 μm is preferably 2.6 μm ² to 650 μm ² . If the most frequent area Q is within a better range, the periodic structure macroscopically becomes a polycrystal with random lattice orientation, so when the surface plasmons are converted into propagating light for radiation on the metal surface, it can be suppressed in a plane The emission angle of the directional radiant light becomes random, so that the luminous light extracted from the device has anisotropy. As shown in FIG. 3, the areas Ca to Cn are random in area, shape, and lattice orientation. Specifically, the degree of randomness of the area preferably satisfies the following conditions. First, draw the ellipse of the largest area circumscribed by the boundary of an area, and express the ellipse by the following formula (1). X ² /a ² + Y ² /b ² = 1 (1) When the average pitch P is less than 500 nm, the standard deviation of πab in the AFM image measurement range of 10 μm×10 μm is preferably 0.08 μm ² the above. When the average pitch P is 500 nm or more and less than 1 μm, the standard deviation of πab in the AFM image measurement range of 10 μm×10 μm is preferably 1.95 μm ² or more. When the average pitch P is 1 μm or more, the standard deviation of πab in the AFM image measurement range of 50 μm×50 μm is preferably 8.58 μm ² or more. If the standard deviation of πab is within a preferable range, the effect of averaging the discharge angle of the surface plasmon radiating from the metal surface to a specific angle to the outside of the device in the plane direction is excellent, thereby suppressing the luminous light from having a directional opposite sex. The degree of randomness of the shapes of Ca to Cn in each region is specifically, the ratio of a to b and the standard deviation of a/b in formula (1) are preferably 0.1 or more. The randomness of the lattice orientation of Ca to Cn in each region specifically, preferably satisfies the following conditions. First, draw a straight line K0 connecting the center points of any two adjacent convex parts in the arbitrary region (I). Next, select one area (II) adjacent to the area (I), and draw three strips connecting any convex part in the area (II) with the center points of the three convex parts adjacent to the convex part Straight line K1～K3. When the straight lines K1 to K3 have an angle that differs by more than 3 degrees with respect to the six straight lines that rotate 60° each time based on the straight line K0, it is defined that the lattice orientations of the region (I) and the region (II) are different. In the area adjacent to the area (I), the area where the lattice orientation is different from the area orientation of the area (I) is preferably 2 or more, preferably 3 or more, and more preferably 5 or more . At this time, the convex side lattices are located in the respective regions Ca to Cn, but they are macroscopically polycrystalline structures. The randomness of the macroscopic lattice orientation can be evaluated by the ratio of the maximum value to the minimum value of the FFT (Fast Fourier Transform). The ratio of the maximum value and the minimum value of the FFT fundamental wave is to obtain the AFM image, find its 2D Fourier transformed image, draw the circle of the wave number leaving the fundamental wave from the origin, and select the point with the largest amplitude and the smallest amplitude on the circle The point is calculated as the ratio of its amplitude. It can be considered that in the case where the maximum value and the minimum value of the FFT fundamental wave are relatively large, the lattice orientation of the convex portion is the same, and when the convex portion is regarded as a two-dimensional crystal, the structure with high single crystallinity is considered. Conversely, it can be considered that when the maximum value and the minimum value of the FFT fundamental wave are relatively small, the lattice orientation of the convex portion is inconsistent, and when the convex portion is regarded as a two-dimensional crystal, it has a polycrystalline structure. The average aspect ratio of the plurality of convex portions 2a to 2n is 0.01 to 1, preferably 0.05 to 0.5. The average aspect ratio refers to the average height H of the convex portions 2a to 2n relative to the average width D of the convex portions 2a to 2n. If the average aspect ratio of the mold 10 is 0.01 or less, the effect of taking out surface plasmons as radiant light cannot be sufficiently obtained in the organic light-emitting diode manufactured using the mold 10. On the other hand, if the average aspect ratio is 1 or more, it is difficult to form the convex portion with the specific curved surface described below. In addition, it is difficult to transfer the shape using the mold 10 when manufacturing the organic light-emitting diode. The average aspect ratio of the convex portions 2a to 2n is measured by AFM. First, an AFM image was obtained for one area of 25 μm ² (5 μm×5 μm) randomly selected for the main surface 10A of the mold 10. Then, a line is drawn in the diagonal direction of the obtained AFM image, and the height and width of each of the plurality of convex portions 2a to 2n intersecting the line are measured. The height of the convex portion refers to the distance from the flat surfaces 1a to 1n to the top of the convex portion, and the width of the convex portion refers to the diameter of the inscribed circle with the center point of the convex portion as the center in a plan view. Then, the average value of the height and width of the convex portion in this region is obtained. Do the same for the 25 randomly selected areas. Then, the average value of the heights and widths of the convex portions of each region obtained at 25 places is averaged to obtain the average height and average width. Then, the average height divided by the average width is the average aspect ratio. More than 80% of the convex portions 2a to 2n are formed by specific curved surfaces. The ratio of the convex portions having a specific curved surface among the plurality of convex portions is more preferably 90% or more, and further preferably 95% or more. The specific curved surface is defined as follows. FIG. 4 is a schematic cross-sectional view of the mold at an arbitrary cross-section passing through the center point of the convex portion, and enlarging one of the convex portions. First, an arbitrary point is selected as the first point p1 from the curved surface 2B constituting the convex portion 2n. Let the tangent plane with respect to this 1st point p1 be 1st tangent plane t1. In addition, a point that deviates from the first point p1 toward the center point 2An of the convex portion 2n by only 1/10 of the average pitch is set as the second point p2. Here, the deviation from only 1/10 of the average pitch refers to a distance L that moves parallel to the flat surface 1 from the first point p1 toward the center point 2An. Let the tangent plane with respect to the second point p2 be the second tangent plane t2. At this time, the inclination angle of the second tangent plane t2 with respect to the first tangent plane t1 is θ. That is, it is convenient for any part of the curved surface 2B of the convex portion 2n to satisfy the relationship that the convex portion 2n is specific when the angle of inclination θ of the second tangent plane t2 relative to the first tangent plane t1 is within 60°. Curved surface. The inclination angle θ is preferably within 45°, and more preferably within 30°. FIG. 5 is a schematic cross-sectional view when the mold of one aspect of the present invention is pressed against the surface of the laminate formed by coating. The laminate 20 includes a first layer 21, a second layer 22, and a third layer 23. When the mold 10 is pressed against the third layer 23 of the laminate 20, the convex portions 2 a to 2 n of the mold 10 are initially pressed against the laminate 20. Therefore, a force F1 is applied to each layer constituting the layered body 20 from the top of the convex portions 2a to 2n toward the outer peripheral portion. By the force F1, the material constituting each layer is also supplied to the space between the plurality of convex portions 2a to 2n of the mold 10. As a result, each layer constituting the laminate 20 is deformed to have a shape corresponding to the mold 10. The force F1 applied to each layer of the laminated body 20 does not concentrate stress and spreads from the top of the pressed convex portions 2a to 2n toward the outer peripheral portion. The reason is that the convex portions 2a to 2n of the mold 10 include a specific curved surface and have a gentle shape. If the force F1 does not concentrate stress, each of the first layer 21, the second layer 22, and the third layer 23 diffuses uniformly in the in-plane direction. Therefore, the thickness of each can be prevented from becoming extremely thin. In addition, generally, the material of each layer is sufficiently supplied along the specific curved surface 2B to the boundary portion 3 between the plurality of convex portions 2a to 2n and the flat surface of the mold 10 which is a portion where voids easily occur. That is, it is also possible to prevent voids from occurring at the boundary 3. In contrast, FIG. 6 is a schematic cross-sectional view when a mold having no specific curved surface is pressed against the surface of the laminate formed by coating. The convex portion 152n of the mold 15 shown in FIG. 6 has a corner portion 155 whose shape changes abruptly. The corner portion 155 is a tangent plane passing through two points of the corner portion 155 and does not satisfy the relationship of a specific curved surface. Therefore, the force F2 applied to each layer constituting the laminate 20 is not uniformly dispersed along the shape of the convex portion 152n, but the stress is concentrated near the corner portion 155. As a result, each of the first layer 21, the second layer 22, and the third layer 23 cannot diffuse uniformly in the in-plane direction. Therefore, each layer may be cut near the corner 155 or the layer thickness may become extremely thin. In addition, a sufficient amount of material cannot be supplied to the boundary 153 between the convex portion 152n and the flat surface, and voids are likely to occur. The layer constituting the laminate 20 corresponds to any layer constituting the organic light-emitting diode. If a part of each layer constituting the organic light-emitting diode is cut off, a problem arises that the cut-off part of the organic light-emitting diode does not emit light, or does not show sufficient light-emitting characteristics. That is, by using the mold 10 of the present embodiment, it is possible to avoid the problem that the organic light emitting diode does not emit light or does not exhibit sufficient light emitting characteristics. Returning to FIG. 5, in order to avoid voids between the mold 10 and the laminate 20, it is preferable that the boundary portion 3 is also gentle. That is, in any of the connecting portions between the convex portions 2a to 2n and the flat surface, it is preferable that the tangent plane at a point that deviates from 1/10 of the average pitch from any 1 point to the tangent at any 1 point The inclination angle of the plane is within 60°. FIG. 7 is a schematic cross-sectional view when another mold of the present invention is pressed against the surface of the laminate formed by coating. The mold 30 shown in FIG. 7 has a plurality of convex portions and a flat surface 31, and a boundary portion 33 of the plurality of convex portions and the flat surface 31 is connected by a specific curved surface. That is, in the connection portion of the flat surface 31 and the convex portion 32n, the inclination angle of the tangent plane at a point deviating from 1 point by 1/10 of the average pitch with respect to the tangent plane at any point is within 60° Relationship. That is, the border 33 becomes gentle. When the mold 30 shown in FIG. 7 is pressed against the laminate 20, neither the force F1 applied from the top of the convex portion 32n toward the outer peripheral portion nor the force F3 applied to the vicinity of the boundary portion 33 is stress-concentrated. Therefore, the materials constituting each layer smoothly diffuse along the main surface of the mold 30. As a result, the gap between the mold 10 and the laminate 20 can be avoided, and the thickness of each layer of the laminate 20 can be made uniform in the in-plane direction. In the mold 30, so that the flat surface 31 and the boundary portion of the plurality of convex portions 33 gentle can meet particular by the bent portion of the convex portion having constituted at least a portion of the inflection p _in, and the inflection portion The first curved portion p1 _in that is closest to the flat surface 31 _in the pin is curved downward and connected to the flat surface 31. Inflection portion p _in a cross-section of the convex portion of the inflection point of the assembly, the curved surface is changed from the upwardly convex portion of the convex curved surface of the downwardly or downwardly from the convex curved surface of the upwardly convex curved change of section . If a top portion of inflection p _in, a convex portion 32n is formed along the line. The closest distance from the first curved portion p1 _in to the flat surface 31 is preferably 1/10 or more of the average pitch P of the plurality of convex portions, and more preferably 1/5 or more. The closest distance refers to the distance of the narrowest part of the width between the first curved portion p1 _1n and the flat surface 31 in the plan view of the convex portion 32n. If the closest distance from the first recurved portion p1 _in to the flat surface 31 is 1/10 or more of the average pitch P of the plurality of convex portions, the inclination of the boundary portion 33 can be made gentler. In addition, if the boundary portion 33 of the mold 30 is smoothed, the layer formed by the vacuum film forming method reflects the reflection of the shape of the transferred object when the layer is formed by the vacuum film forming method on the object to be transferred made using the mold 30 Sexual improvement. FIG. 8 is a schematic cross-sectional view when a layer is formed on the transfer material shown in FIG. 7 by a vacuum film forming method. In the mold 30 shown in FIG. 7, the boundary portion 33 between the flat surface 31 and the convex portion 32n is gentle. Therefore, the boundary portion 23A of the curved surface 20A formed on the outermost surface of the laminate 20 using the mold 30 is also gentle. The part whose shape changes abruptly is generally a large change in the dispersion of film-forming particles during vacuum film-forming. On the other hand, if the shape of the curved surface 20A including the boundary portion 23A is gentle, the dispersion of the film-forming particles does not change significantly, and a uniform layer can be formed. The main surface (outermost surface) 20A of the transfer material layered body 20 shown in FIG. 8 is relatively gentle. Therefore, the outer surface 26B of the vacuum-formed layer 26 can sufficiently reflect the shape of the main surface 20A. Here, the "fully reflected" means that it is not necessary to fully reflect the shape formed in the stamping step. If the average pitch of the convex portions constituting the outer surface 26B of the vacuum film-forming layer 26 is within ±10% compared to the average pitch of the convex portions constituting the main surface 20A, and the outer surface of the layer 26 constituting the vacuum film forming The average height of the convex portions of 26B is within ±10% compared to the average height of the convex portions constituting the main surface 20A, and it can be said that the outer surface 26B of the vacuum-formed layer 26 sufficiently reflects the shape of the main surface 20A. For the measurement of the average pitch mentioned here, the above-mentioned method for measuring the average pitch P can be applied. In addition, the measurement method of the average height H mentioned above can be applied to the measurement of the average height. In the case where the vacuum-formed layer 26 is an electrode, it is not necessary for the outer surface 26B to sufficiently reflect the shape of the main surface 20A. In this case, since the main surface 20A is gentle, the film thickness of the layer 26 does not become thin or cut. As a method of confirming the shape of the curved surface 22B or the outer surface 26B, a cross-sectional observation using a scanning electron microscope (SEM) or a transmission electron microscope (TEM) may be mentioned, or the three-dimensional after removing the layer covering the observation surface Observed by electron microscope or AFM. Returning to FIG. 1, the area ratio of the flat surfaces 1a to 1n in the main surface 10A is preferably 5 to 50%, and more preferably 5% to 30%. If the area ratio of the flat surfaces 1a to 1n in the main surface 10A is 5% or more, the aspect ratio of the irregularities that can be used to extract the surface plasmons in the organic light-emitting diode manufactured using the mold becomes smaller. On the other hand, if the area ratio of the flat surfaces 1a to 1n in the main surface 10A is 50% or less, in the organic light-emitting diode manufactured using this mold, surface plasmons can be suppressed from being trapped by the flat surface. 9 is a schematic cross-sectional view of a mold of one aspect of the present invention cut by connecting the surfaces between the centers of adjacent convex portions. More specifically, it is a cross-sectional view taken along the plane connecting the center points of the adjacent convex portions in FIG. 1. The broken line in FIG. 9 is an approximate curve of the convex portions 2a to 2n. The approximate curve can be obtained by approximating the normal distribution by setting the center points 2Aa to 2An of the convex portions 2a to 2n as vertices. The boundary between the convex portions 2a to 2n and the ridge portion 4 is an approximate curve. The adjacent convex portions are connected by the ridge portion 4. The sides closer to the center point 2Aa to 2An of the approximate curve are the convex portions 2a to 2n, and the opposite side is the ridge portion 4. Preferably, the connection portion of the ridge portion 4 and the convex portions 2a to 2n and the connection portion of the ridge portion 4 and the flat surfaces 1a to 1n are connected in such a manner as to satisfy the condition of a specific curved surface. By connecting these connecting portions in such a manner as to satisfy the conditions of the specific curved surface, the force generated when the mold 10 is pressed against the laminate can be more evenly dispersed. In other words, it is possible to suppress the layer constituting the laminate pressed against the mold 10 from being cut. Further, as shown in FIG. 9, it is preferable that at least a part of the ridge portion 4 exists on the flat surface 1n side of the convex portion 2n connecting the ridge portion 4. That is, it is preferable that the height h of the portion of the ridge portion 4 closest to the flat surface 1n is smaller than the height H of the convex portion 2n connecting the ridge portion 4 from the flat surface 1n. FIG. 13 is a view of the main part of the mold of the present embodiment viewed from the direction perpendicular to the flat surface. If the height h of the ridge portion 4 is lower than the height H of the convex portion 2n, when the mold is pressed against the transferred object, the air interposed between the mold and the transferred object is removed through this portion (Fig. 13 arrow). In other words, it is possible to prevent air from being mixed into the object to be transferred, thereby performing uniform transfer. In addition, as shown in FIG. 13, in a plan view from a direction perpendicular to the flat surface 1n, the tops of the plurality of convex portions 2a to 2n are located at the apexes of hexagons constituting a honeycomb lattice (hexagonal lattice) At this time, the diffusion of resin and the like when the mold is pressed against the transferred object becomes equal, and pressure can be applied to the transferred object equally. If the pressure can be uniformly applied, for example, even when the transfer object is a thin layer, the layer can be prevented from being cut or the layer thickness becomes extremely thin. Further, the height h from the flat surface 1n of the portion of the ridge portion 4 shown in FIG. 9 closest to the flat surface 1n is preferably higher than the height H from the flat surface 1n of the convex portion 2n connecting the ridge portion 4 50% to 90%, more preferably 60 to 85%. If the height h of the ridge portion 4 is too low, the strength of the mold decreases, and if the height h of the ridge portion 4 is too high, the escape path of air becomes less. So far, one embodiment of the present invention has been described using the mold 10 of FIG. 1 as an example, but the shape of the mold is not limited to this configuration. 10 is a perspective schematic view of another aspect of the mold of the present invention. The mold 40 shown in FIG. 10 is different from the above-described mold 10 in that the convex portions 42a to 42n are arranged apart from each other and includes one flat surface 41. In addition, for example, it may be configured as shown in FIG. 11. FIG. 11 is a perspective schematic view of another aspect of the mold of the present invention. As shown in FIG. 11, the mold 50 has a plurality of convex portions 52a to 52n and a plurality of flat surfaces 51a to 51n. The mold 10 shown in FIG. 1 and the mold 50 shown in FIG. 11 are such that the positional relationship between the convex portion and the flat surface is reversed. That is, in the mold 50, the plurality of convex portions 52a to 52n are arranged in a region surrounded by the most adjacent flat surface among the plurality of flat surfaces 51a to 51n. In FIG. 11, if the center point of the most adjacent flat surface is connected, a hexagon is viewed from above, and a convex portion is provided in the central area. That is, when the positional relationship between a plurality of convex portions 52a to 52n and the flat surfaces 51a to 51n is reversed like the mold 50, each convex portion 52a to 52n is also formed by a specific curved surface, so it is pressed against the mold 50 In the stamping step, the layer constituting the laminate can be suppressed from being cut. The mold of one aspect of the present invention has a convex portion having a specific curved surface. Therefore, the organic light-emitting diode manufactured by using the mold 10 does not have a portion with a thin layer thickness or a portion where no layer is formed, and the surface plasmon can be taken out efficiently. "Mold manufacturing method" The mold can use electron beam lithography, mechanical cutting, laser lithography, laser thermal lithography, interference exposure, narrow exposure, aluminum anodic oxidation method and particle masking method. form. Among them, it is preferable to use a method of using a particle mask to make a mold. The method of using a particle mask refers to a method of performing an etching process after forming a particle single-layer film on the flat surface of the base material of the mold as an etching mask. In the method of using a particle mask, the base material directly below the particles is not etched and becomes a convex portion. Hereinafter, a specific example of the method of using the particle mask will be described. 14 is a diagram schematically showing a method of manufacturing a mold. First, a single-particle film etching mask 62 containing a plurality of particles M is formed on the base 61 (FIG. 14(a)). As a method of forming the single-particle film etching mask 62 on the substrate 61, for example, a method using the so-called LB method (Langmuir-Blodgett method) can be used. Specifically, the method of forming the single-particle film etching mask 62 includes: a dropping step, which adds dispersed droplets formed by dispersing particles in a solvent to the liquid surface in the water tank; a single-particle film forming step, which uses A single particle film F containing particles is formed by volatilizing the solvent; and a migration step, which is to take the single particle film F onto the substrate. Each step will be specifically described below. (Dropping step and single particle film forming step) First, in a hydrophobic organic solvent containing one or more hydrophobic solvents such as chloroform, methanol, ethanol, methyl ethyl ketone, etc., the surface is hydrophobic Particles to prepare dispersions. In addition, as shown in FIG. 15, a water tank (tank) V is prepared, and water W is added as a liquid for spreading particles on the liquid surface (hereinafter, sometimes referred to as lower layer water). Then, the dispersed droplets are added to the liquid surface of the lower layer water (dropping step). Then, the solvent as the dispersion medium evaporates, and the particles spread out in a single layer on the liquid surface of the lower layer water, thereby forming the two-dimensionally most densely packed single particle film F (single particle film forming step). As such, in the case of selecting a hydrophobic one as particles, a hydrophobic one must also be selected as a solvent. On the other hand, in this case, the lower layer water must be hydrophilic, and generally, water is used as described above. By such a combination, the self-assembly of particles is advanced as described below to form a two-particle densely packed single particle film F. However, hydrophilic particles can also be selected as the particles and the solvent. In this case, as the lower layer water, a hydrophobic liquid is selected. (Transition step) As shown in FIG. 15, the single-particle film F formed on the liquid surface by the single-particle film formation step is transferred onto the substrate 61 that is the object to be etched while maintaining the single-layer state (transition step). The base 61 may have a planar shape, or may include a non-planar shape such as a curved surface, an inclination, and a step difference in part or all. The single particle film F covers the surface of the substrate while maintaining the two-dimensional densest filling state even if the substrate 61 is not flat. The specific method of transferring the single-particle film F onto the substrate 61 is not particularly limited. For example, as the first method, it is also possible to keep the basal substrate 61 on the one hand while keeping it substantially parallel to the single-particle film F, and to touch the single-particle film F while descending from above. The affinity of the film F with the base 61 causes the single-particle film F to move to the base 61. In addition, as a second method, before forming the single-particle film F, the substrate 61 may be arranged in a substantially horizontal direction in the water under the water tank in advance, and after forming the single-particle film F on the liquid surface, the liquid surface may be gradually lowered, thereby reducing The single particle film F is transferred onto the base 61. According to these methods, the single particle film F can be transferred onto the substrate 61 without using a special device. Even if it is a single-particle film F having a larger area, it can be easily transferred to the substrate 1 while maintaining its second most densely packed state. In this respect, the so-called LB tank method is preferably used. By this transition step, a plurality of particles M are arranged in a substantially single layer on a flat surface 61a which is a surface of the base 61. That is, the single particle film F of the particles M is formed on the flat surface 61a. (Etching step) The single particle film F thus formed functions as a single particle etching mask 62. The substrate 61 provided with the single-particle etching mask 62 on one side is subjected to vapor-phase etching to perform surface processing (etching step). Specifically, when vapor phase etching is started, first, as shown in FIG. 14(b), the etching gas passes through the gap of the particles M constituting the etching mask 62 and reaches the surface of the base 61, and a groove is formed in this portion. Then, cylinders 63 appear at positions corresponding to the particles M, respectively. A groove portion 61m is formed between the columns 63. The groove portion 61m is formed at the center of the three particles M arranged on the regular triangle by the closest packing. Therefore, the groove portion 61m is located at the vertex of the regular hexagon with the cylinder 63 as the center. The particles M constituting the single-particle film etching mask 62 are not particularly limited, and for example, gold particles, colloidal silicon oxide particles, or the like can be used. As the etching gas, generally used gas can be used. For example, Ar, SF ₆ , F ₂ , CF ₄ , C ₄ F ₈ , C ₅ F ₈ , C ₂ F ₆ , C ₃ F ₆ , C ₄ F ₆ , CHF ₃ , CH ₂ F ₂ , CH _{3 can be used} F, C ₃ F ₈ , Cl ₂ , CCl ₄ , SiCl ₄ , BCl ₂ , BCl ₃ , BC ₂ , Br ₂ , Br ₃ , HBr, CBrF ₃ , HCl, CH ₄ , NH ₃ , O ₂ , H ₂ , N ₂ , CO, CO ₂ etc. The particles M and the etching gas can be changed according to the substrate 61 to be etched. For example, in the case where gold particles are selected as the particles M constituting the single-particle film etching mask 62, and the glass substrate is selected as the base 61 and these combinations are used, if the etching gas uses CF ₄ , CHF _3, etc. and the glass has For the reactive ones, the etching speed of the gold particles relatively slows down, and the glass substrate is selectively etched. The molds of various shapes shown in FIGS. 1, 10, and 11 can obtain a desired shape by changing dry etching conditions. In addition, in order to make the surface shape of the convex portion smoother, wet etching may be used together. Examples of the conditions for dry etching include the material of the particles constituting the particle mask, the material of the original plate, the type of etching gas, the bias power, the power supply, the flow rate and pressure of the gas, and the etching time. The flat surface can be obtained by increasing the initial etching gas flow rate and gradually decreasing the flow rate. In addition, when the ridge portion remains as in the mold 10 shown in FIG. 1, it can be obtained by increasing the hardness of the particles used for the particle mask. The average pitch of the convex portions and the like can be freely changed by changing the particle size of the particles used. In addition, when a non-periodic structure is formed using a single-layered particle film, it can be produced by using a plurality of particles having different particle diameters. (Odd number transfer step) Then, the base 61 shown in FIG. 14(b) is subjected to odd number transfer. The transfer body 71 shown in FIG. 14(c) is obtained by an odd number of transfers. Specifically, first, the produced base 61 is transferred with resin. On the surface of the obtained resin transfer product, metal plating such as Ni is coated by electroforming or the like. The hardness of the transfer body 71 is increased by coating metal plating, and the following shape adjustment and the like can be performed. The top of the cylinder 63 of the base 61 is flat because it is covered with particles M. Therefore, a flat surface 71n is formed in the transfer body 71 at a position corresponding to the cylinder 63 of the base 61. In addition, a convex portion 72n is formed in the transfer body 71 at a position corresponding to the groove portion 61m of the base 61. Therefore, the convex portion 72 is located at the vertex of the regular hexagon with the flat surface 71n as the center. That is, the shape corresponding to FIG. 1 is obtained. (Shape adjustment step) However, there is a case where a specific curved surface is not formed on the surface of the transfer body 71. For example, a corner 72a may be formed on the top of the convex portion 72n. The corner 72a is a part that does not satisfy the specified curved surface. Therefore, the corner portion 72a is removed to make the outer surface of the convex portion 72n a specific curved surface. Further etching can be performed either by wet etching or dry etching. Hereinafter, the case of dry etching will be specifically described. In order to remove the corner portion 72a, as shown in FIG. 14(d), the transfer body 71 is irradiated with plasma P generated by a plasma etching device to perform physical etching. The physical etching is different from the reactive etching used in the etching step. Reactive etching advances etching by reacting the plasma chemical species with the transfer body 71. On the other hand, the physical etching is performed by the physical force that the plasma chemical species conflict with the transfer body 71. Therefore, the physical etching is caused by the uneven probability of etching between the higher probability and the lower probability of the chemical species conflict in plasma, and has anisotropic etching compared with reactive etching. Physical etching is similar to ashing. In the plasma etching device, the chemical species plasmatized is used between the upper electrode and the lower electrode. Specifically, the lower electrode at a low potential is electrically connected to the transfer body 71 to charge the transfer body 71. The chemical species plasmatized between the upper electrode and the lower electrode are attracted by the transfer body 71 at a low potential and collide toward the transfer body 71 at high speed. At this time, there is a property that if there is a sharp portion like the corner portion 72a in the charged transfer body 71, the electric charge is concentrated in this portion. Therefore, most of the plasma chemical species are attracted to the sharp parts. That is, the sharp part is more likely to collide with the plasma chemical species than other parts. If the probability of conflict with the plasma chemical species increases, this part will be etched faster than other parts. That is, the corner portion 72a of the convex portion 72 is gradually removed to form a convex portion 2n having a specific curved surface (FIG. 14(e)). As an etching gas used for physical etching, for example, a rare gas such as argon, oxygen, or the like can be used. The lack of reactivity of these gases promotes physical etching. In addition, as an etching gas for physical etching, a reactive etching gas may also be used. For example, reactive gases such as CF ₄ and CHF ₃ can be used. In this case, the etching conditions are adjusted in such a way that the etching using physical conflicts becomes more prominent than the chemical reactivity of the ion species. For example, the etching conditions are adjusted so that the potential difference between the upper electrode and the lower electrode becomes larger. If the potential difference between the upper electrode and the lower electrode becomes larger, the collision speed of plasma chemical species increases, and the effect of physical etching becomes more significant than the effect of reactive etching. Preferably, the physical etching is performed under low pressure and high bias using argon or oxygen. The specific conditions vary depending on the device, so they cannot be determined at all. For example, in the case of dry etching using inductively coupled plasma (ICP), it is preferable to apply 0.5 to 1.5 W/cm at a pressure of 0.5 to 1.0 Pa ² bias. Even when it is convenient to use other dry etching gas, it will not deviate greatly from the above range, but it is preferable to shorten the processing time. The reason for this is that there is a faster etching speed, and the corner portion 62a is supposed to be etched as described above. So far, only the corner portion 72a has been mentioned. For example, a sharp portion may be formed in the ridge portion (refer to FIGS. 1 and 9) between adjacent convex portions 72n. To facilitate this situation, the sharp portion of the ridge portion can be removed simultaneously with the corner portion 72a by physical etching. (Replication step) The mold produced by the above method can be used directly as a mold, or a replica made with the produced mold as the original version can be used as a mold for real-time use. Reproduction can be made by transferring the produced mold even times. Specifically, first, the produced mold is transferred with resin. On the surface of the obtained odd-numbered transfer body, metal plating such as Ni is coated by electroforming or the like. By coating the metal plating to increase the hardness of the odd-numbered transfer body, further transfer can be performed. Then, the odd-numbered transfer body is further transferred to produce an even-numbered transfer body. The even-numbered transfer body has the same shape as the produced mold. Finally, on the surface of the even-numbered transfer body, metal such as Ni is plated by electroforming or the like, thereby completing the replication of the mold. In addition, a mold 30 in which the boundary portions 33 of the plurality of convex portions 32n and the flat surface 31 shown in FIG. 7 are also connected by a specific curved surface can be produced by the following method. For example, as the first method, there is a method of performing physical etching between the above-mentioned etching step and the odd number of transfer steps. By performing physical etching between the etching step and the odd number of transfer steps, the top of the cylinder 63 becomes gentle, and the shape of the concave portion of the transfer body 71n becomes gentle. As another method, there is a method of performing physical etching during the transfer process in the copying step. By performing physical etching, the shape of the portion that becomes the convex portion after transfer can be smoothed. "Organic Light Emitting Diode" FIG. 12 is a schematic cross-sectional view of an organic light emitting diode device 100 according to one aspect of the present invention. The organic light-emitting diode element 100 includes a base 110, a first electrode 120, an organic semiconductor layer 130 including a light-emitting layer 133, and a second electrode 140 in this order. The organic semiconductor layer 130 shown in FIG. 12 has a hole injection layer 131 and a hole transport layer 132 between the first electrode 120 and the light emitting layer 133 in addition to the light emitting layer 133, and the light emitting layer 133 and the second electrode 140 An electron transport layer 134 and an electron injection layer 135 are provided between them. Each of the hole injection layer 131, the hole transport layer 132, the electron transport layer 134, and the electron injection layer 135 is not necessary or required. The organic light-emitting diode element 100 of the present invention may further include other layers as long as the effects of the present invention are not impaired. The first electrode 120 and the second electrode 140 of the organic light emitting diode apply a voltage to the organic semiconductor layer 130. When a voltage is applied between the first electrode 120 and the second electrode 140, electrons and holes are injected into the light-emitting layer 133, and the coupling generates light. The generated light directly passes through the first electrode 120 and is taken out to the outside of the device, or after being reflected once by the second electrode 140, it is taken out to the outside of the device. The second electrode 140 has a two-dimensional structure in which a plurality of convex portions 142a to 142n are two-dimensionally arranged on the surface 140A on the side of the light emitting layer 133. The two-dimensional structure is the same as the above-mentioned mold, which can be periodic or non-periodic. The average pitch of the plurality of convex portions 142a to 142n is 50 nm to 5 μm, preferably 50 nm to 500 nm. The average pitch can be obtained by the same method as the average pitch in the mold. If the average pitch of the convex portions 142a to 142n is within this range, the energy captured in the form of surface plasmons on the surface 140A of the second electrode which is a metal electrode can be efficiently radiated and can be extracted as light. The average aspect ratio of the plurality of convex portions 142a to 142n is 0.01 to 1, preferably 0.05 to 0.5. The average aspect ratio can be obtained by the same method as the average aspect ratio in the mold. If the average aspect ratio of the convex portions 142a to 142n in the surface of the second electrode 140 on the light emitting layer side is within this range, the surface 140A of the second electrode which is a metal electrode can be captured by surface plasmon The energy is radiated efficiently so that it can be taken out as light. The capture of surface plasmons is generated in the following process. When the light-emitting layer 133 emits light from the light-emitting molecules, near-field light is generated in the extreme vicinity of the light-emitting point. Since the distance between the light-emitting layer 133 and the second electrode 140 is very close, the near-field light is converted into the energy of the propagating surface plasmon on the surface of the second electrode 140. The propagating surface plasmons on the metal surface are those in which the sparse and dense waves of free electrons generated by incident electromagnetic waves (near-field light, etc.) accompany the surface electromagnetic fields. In the case of surface plasmons existing on a flat metal surface, the dispersion curve of the surface plasmons does not cross the dispersion line of light (spatially propagating light). Therefore, the energy of the surface plasmons cannot be extracted as light. In contrast, if the metal surface has a two-dimensional periodic structure, the dispersion curve of the surface plasmon diffracted by the two-dimensional periodic structure crosses the dispersion curve of the spatially propagated light. As a result, the energy of the surface plasmons can be taken out as radiation light to the outside of the device. In this way, if a two-dimensional periodic structure is provided, the energy of light lost in the form of surface plasmons is extracted. The extracted energy is radiated from the surface of the second electrode 140 as space propagating light. At this time, the directivity of the light radiated from the second electrode 140 is high, and most of it is directed to the extraction surface. Therefore, high-intensity light is emitted from the extraction surface, thereby improving extraction efficiency. More than 80% of the plurality of convex portions 142a to 142n have a specific curved surface. The specific curved surface is defined in the same way as the specific curved surface in the mold. A flat surface 141 is formed between the plurality of convex portions 142a to 142n on the surface 140A of the second electrode. The area ratio occupied by the flat surface 141 is preferably 5-50%, more preferably 5%-30%. If the area ratio of the flat surface 141 in the surface 140A of the second electrode is 5% or more, the aspect ratio of the irregularities used to extract the surface plasmons can be reduced. On the other hand, if the area ratio of the flat surface 141 in the surface 140A of the second electrode is 50% or less, the surface plasmons captured by the surface 140A of the second electrode can be efficiently converted into light. The second electrode 140 is preferably a material having a larger negative absolute value of the real part of the complex dielectric constant, and it is preferable to select a metal material with a higher plasma frequency that is advantageous for the extraction of surface plasma . Examples of this material include monomers such as gold, silver, copper, aluminum, and magnesium, or alloys of gold and silver, and alloys of silver and copper. If the light emission of the organic light-emitting diode is taken into consideration, it is preferably a metal material having a resonance frequency in the entire visible light region, and particularly preferably silver or aluminum. The second electrode 140 may have a laminated structure of two or more layers. The thickness of the second electrode 140 is not particularly limited. For example, it is 20 to 2000 nm, preferably 50 to 500 nm. If it is thinner than 20 nm, the reflectance becomes lower and the front brightness decreases. If it is thicker than 500 nm, heat or radiation-induced damage during film formation, and mechanical damage due to film stress accumulate in the organic light-emitting layer 133 etc. include organic layers. The organic semiconductor layer 130 contains an organic material. In FIG. 12, a concave-convex shape is formed at the interface between the light-emitting layer 133 and the electron transport layer 134 of the organic semiconductor layer 130 and the interface between the electron transport layer 134 and the electron injection layer 135. This uneven shape becomes the opposite shape of the main surface 10A of the mold 10. The uneven shape does not necessarily need to be formed at the interface between the light emitting layer 133 and the electron transport layer 134 of the organic semiconductor layer 130 and the interface between the electron transport layer 134 and the electron injection layer 135. The details will be described below in the method of manufacturing an organic light-emitting diode, and the uneven shape only needs to be formed on the surface of the second electrode 140 side of any layer constituting the organic semiconductor layer. The layer on the second electrode 140 side has a shape that reflects the uneven shape as compared to the layer formed with the uneven shape. The light emitting layer 133 includes an organic light emitting material. Examples of the organic light-emitting material include tri[1-phenylisoquinoline-C2,N]iridium(III)(Ir(piq)3), 1,4-bis[4-(N,N-diphenylamino Pigment compounds such as styrylbenzene)] (DPAVB), bis[2-(2-benzoxazolyl)phenol] zinc (II) (ZnPBO). In addition, those obtained by doping a fluorescent dye compound or a phosphorescent material with another substance (host material) may also be used. In this case, examples of the host material include hole transport materials and electron transport materials. As materials constituting the hole injection layer 131, the hole transport layer 132, the electron transport layer 134, and the electron injection layer 135, organic materials are generally used, respectively. For example, examples of the material (hole injection material) constituting the hole injection layer 131 include 4,4',4''-tri[2-naphthylphenylamino]triphenylamine (2-TNATA), etc. Compounds etc. Examples of the material (hole transport material) constituting the hole transport layer 132 include N,N'-diphenyl-N,N'-bis(1-naphthyl)-(1,1'-biphenyl) -4,4'-diamine (NPD), copper phthalocyanine (CuPc), N,N'-diphenyl-N,N'-bis(m-methylphenyl)aminobiphenyl (TPD) and other aromatic Amine compounds, etc. Examples of the material (electron transport material) constituting the electron transport layer 134 and the material (electron injection material) constituting the electron injection layer 135 include 2,5-bis(1-naphthyl)-1,3,4-

Diazole (BND), 2-(4-tert-butylphenyl)-5-(4-biphenyl)-1,3,4-

Diazole (PBD), etc.

Metal complex compound compounds such as oxadiazole compounds and tris(8-quinolinyl) aluminum (Alq). The thickness of the entire organic semiconductor layer including the light-emitting layer 133 is usually 30 to 500 nm. For the first electrode 120, a transparent conductor that transmits visible light is used. The transparent conductor constituting the first electrode 120 is not particularly limited, and a known one can be used as a transparent conductive material. For example, indium tin oxide (Indium Tin Oxide (ITO)), indium zinc oxide (Indium Zinc Oxide (IZO)), zinc oxide (Zinc Oxide (ZnO)), zinc tin oxide (Zinc Tin Oxide (ZTO)), etc. . The thickness of the first electrode 120 is usually 50 to 500 nm. The base 110 uses a transparent body that transmits visible light. The material constituting the base 110 may be an inorganic material, an organic material, or a combination thereof. Examples of the inorganic material include various glasses such as quartz glass, alkali-free glass, and white glass, and transparent inorganic minerals such as mica. Examples of the organic material include resin films such as cycloolefin-based films and polyester-based films, and fiber-reinforced plastic materials obtained by mixing fine fibers such as cellulose nanofibers with the resin films. Although depending on the application, generally, the base 110 uses a higher visible light transmittance. The following is used, that is, the transmittance in the range of visible light (wavelength 380 nm to 800 nm) is not biased in the spectrum and is 70% or more, preferably 80% or more, and more preferably 90% or more. The thickness of each layer constituting the organic light-emitting diode 100 can be measured by a spectroscopic ellipsometer, a contact step difference meter, AFM, or the like. "Manufacturing method of organic light-emitting diode" The manufacturing method of an organic light-emitting diode according to one aspect of the present invention is on a surface of a substrate with electrodes having a transparent first electrode on which the first electrode is formed, A manufacturing method of forming an organic light-emitting diode including an organic semiconductor layer including a light-emitting layer and a second electrode through a coating step and a subsequent vacuum film-forming step. Between the coating step and the vacuum film-forming step, the outermost surface of the coating layer formed by the coating step is pressed against the outermost surface of the coating layer, and the shape of the main surface of the mold is formed on the outermost surface of the coating layer Invert the shape of the stamper step. <Preparation step of substrate with electrode> The substrate system with electrode forms a transparent first electrode on a transparent substrate. The substrate and the first electrode can be used as described above. As a method of forming the first electrode on the substrate, a known method can be used. For example, a transparent electrode material such as ITO can be formed on the substrate by sputtering. In addition, commercially available substrates with electrodes can also be purchased. <Coating Step> In the coating step, a part of or all of the layers constituting the organic semiconductor layer are formed by coating. Generally speaking, in the coating step, the solvent of the coating liquid must be selected in such a way as not to invade the layers that have been formed to the previous step, so the more the number of layers formed by coating, the more difficult it is to select the appropriate Solvent. Therefore, in the coating step, it is preferable to form up to the light emitting layer among the layers constituting the organic semiconductor layer. A well-known method can be used for a coating method, For example, spin coating, bar coating, slit coating, die coating, spray coating, an inkjet method, etc. can be used. The coating method does not need to make the environment during lamination to be vacuum, and does not require large-scale equipment. In addition, since time such as vacuuming is not required, the output of manufacturing organic light-emitting diodes can be increased. <Stamping step> The stamping step is a method of forming an uneven shape by a so-called imprint method. If the mold is pressed against the coating layer formed in the coating step, the coating liquid constituting the coating layer follows the shape of the mold. Since the coating liquid has a viscosity that can maintain the shape, the shape is maintained even after the mold is removed. In addition, even after the coating liquid is dried and evaporated, when the material forming the film-forming layer has a glass transition point, the shape can be given by pressing the mold against the mold while heating the film-forming layer above the glass transition point . In the stamping step, the mold of one aspect of the present invention is pressed against the outermost layer of the coating layer formed in the coating step. The so-called outermost layer refers to the last layer formed in the coating step, and is the layer farthest from the substrate at the end of the coating step. For example, in the case where the light-emitting layer 133 of FIG. 12 is formed by coating, the mold is pressed against the surface of the light-emitting layer 133 on the side of the second electrode 140 to transfer the inverted shape of the mold. As described above, the mold of one aspect of the present invention has a plurality of convex portions and a flat surface, and the plurality of convex portions have a specific curved surface. Therefore, when the mold is pressed against the light-emitting layer 133, the force applied to the light-emitting layer 133 is dispersed along a specific curved surface. As a result, it is possible to avoid the case where the thickness of the light-emitting layer 133 becomes extremely thin or the case where the light-emitting layer 133 is cut. <Vacuum film forming step> In the vacuum film forming step, the layer and the second electrode that are not formed in the coating step among the layers that constitute the organic semiconductor layer are formed by the vacuum film forming method. As the vacuum film formation method, a vacuum evaporation method, a sputtering method, a CVD (chemical vapor deposition) method, or the like can be used. In order to reduce damage to the organic layer, it is preferable to use a vacuum evaporation method as the vacuum film formation method. Compared with the coating method, the vacuum film forming method reflects the shape of the substrate with higher reflectivity. Therefore, the shapes of the convex portion and the flat surface formed on the outermost layer of the coating layer in the stamping step are also reflected in the layer stacked on the uppermost layer of the coating layer. In the concave portion formed in the outermost layer of the coating layer by pressing against the mold, the concave portion and the flat surface are preferably connected by a specific curved surface. That is, it is preferable that the boundary between the concave portion and the flat surface is gentle. It is possible to further suppress the uneven thickness of the layer formed by vacuum film formation. Since the outermost layer of the coating layer forms the above-mentioned concave portion and flat surface, the surface on the light emitting layer side of the second electrode is formed as shown in FIG. 12 in a shape reverse to the outermost layer of the coating layer. The shape is a shape reflecting the shape of the mold pressed in the compression molding step. In the method for manufacturing an organic light-emitting diode according to one aspect of the present invention, since there is a stamping step using a mold having a specific shape, it is possible to easily form desired irregularities on the light-emitting layer side of the second electrode. The organic light-emitting diode manufactured by this method can take out the surface plasmon, so as to obtain higher light-emitting characteristics.

1a～1n‧‧‧Flat surface 1Aa～1An‧Center point 2a～2n‧‧‧Convex part 2Aa～2An‧‧‧Center point 2B‧‧‧Curved surface 3‧‧‧Boundary part 4‧‧‧Edge part 10‧‧‧Mold 10A‧‧‧Main surface 15‧‧‧Mold 20‧‧‧Layered body 20A‧‧‧Curved surface 21‧‧‧1st layer 22‧‧‧second layer 23‧‧‧third layer 23A ‧‧‧Boundary 26‧‧‧ Layer 26B‧‧‧Outer surface 30‧‧‧Mold 31‧‧‧Flat surface 32n‧‧‧Convex portion 33‧‧‧Border 40 40‧‧‧Mold 41‧‧‧Flat surface 42a～42n‧‧‧Convex part 50‧‧‧Mold 51a～51n‧‧‧Flat surface 52a～52n‧‧‧Convex part 61‧‧‧Matrix 61m‧‧‧Slot part 62‧‧‧Single particle film etching mask 63‧‧‧Cylinder 71‧‧‧Transfer body 71n‧‧‧Flat surface 72a‧‧‧Corner 72n‧‧‧Convex part 100‧‧‧Organic light-emitting diode 110‧‧‧Substrate 120‧‧‧ 1st Electrode 130‧‧‧ organic semiconductor layer 131‧‧‧ hole injection layer 132‧‧‧ hole transport layer 133‧‧‧ light emitting layer 134‧‧‧ electron transport layer 135‧‧‧ electron injection layer 140‧‧‧ 2nd Electrode 140A‧‧‧surface 141‧‧‧flat surface 142a～142n‧‧‧convex part 152n‧‧‧convex part 155‧‧‧corner part F1‧‧‧force F2‧‧‧force F3‧‧‧force h‧‧ ‧Height H‧‧‧Average height K0, K1～K3 ‧‧‧Straight line M‧‧‧Particle p1‧‧‧1st point p1 _in ‧‧‧1st curvature part p2‧‧‧2nd point p _in ‧‧ ‧Recurve P‧‧‧Average pitch P‧‧‧Plasma t1‧‧‧First cut plane t2‧‧‧Second cut plane u‧‧‧Circular V‧‧‧Sink (groove) W‧‧‧Water θ‧‧‧Tilt angle

FIG. 1 is a perspective schematic view of a mold of one aspect of the present invention. 2 is a schematic cross-sectional view of a mold of one aspect of the present invention cut along a plane passing through a center point of a convex portion formed on the mold and a center point of a flat surface. FIG. 3 is a schematic top view of a mold of one aspect of the present invention. FIG. 4 is a view of a mold of one aspect of the present invention cut at a plane passing through a center point of a convex portion formed in the mold, and an enlarged cross-sectional view of one convex portion. FIG. 5 is a schematic cross-sectional view when the mold of one aspect of the present invention is pressed against the surface of the laminate formed by coating. FIG. 6 is a schematic cross-sectional view when a mold having no specific curved surface is pressed against the surface of the laminate formed by coating. FIG. 7 is a schematic cross-sectional view when another mold of the present invention is pressed against the surface of the laminate formed by coating. 8 is a schematic cross-sectional view when a layer is formed on the transfer material shown in FIG. 7 by a vacuum film forming method. 9 is a schematic sectional view taken along the adjacent convex portion of the mold of one aspect of the present invention. 10 is a perspective schematic view of another aspect of the mold of the present invention. FIG. 11 is a perspective schematic view of another aspect of the mold of the present invention. 12 is a schematic cross-sectional view of an organic light-emitting diode device according to an aspect of the present invention. FIG. 13 is a view of the main part of the mold of the present embodiment viewed from the direction perpendicular to the flat surface. 14A to 14E are diagrams schematically showing a method of manufacturing a mold. 15A and 15B are diagrams schematically showing a dropping step and a single particle film forming step in the manufacturing process of a mold.

1a~1n‧‧‧flat surface

1Aa~1An‧‧‧Center

2a~2n‧‧‧Convex part

2Aa~2An‧‧‧Center

10‧‧‧Mold

10A‧‧‧Main

P‧‧‧ average spacing

Claims (9)

A method for manufacturing an organic light-emitting diode, characterized in that the first step described above is formed on a substrate with an electrode having a transparent first electrode on the substrate through a coating step and a subsequent vacuum film-forming step On the surface of the electrode, an organic semiconductor layer including a light-emitting layer and a second electrode are formed, and there is a stamper step between the coating step and the vacuum film forming step, which presses the mold against the coating The outermost surface of the coating layer formed in the step, and the inverted shape of the main surface of the mold is formed on the outermost surface of the coating layer, the mold has a flat surface and a plurality of convex portions on the main surface , The average pitch of the plurality of convex portions is 50 nm to 5 μm, the average aspect ratio of the plurality of convex portions is 0.01 to 1, more than 80% of the plurality of convex portions have a specific curved surface, the specific curved surface is The arbitrary point of the specific curved surface is set as the first point, and when the point deviating from the first point by only 1/10 of the average pitch is set as the second point, the second point that is in contact with the second point The inclination angle of the tangent plane with respect to the first tangent plane that is in contact with the first point is within 60°. The method for manufacturing an organic light emitting diode according to claim 1, wherein the area ratio of the flat surface among the main surfaces is 5 to 50%. The method for manufacturing an organic light emitting diode according to claim 1, wherein the flat surface and the convex portion having the specific curved surface are connected in a manner satisfying the condition of the specific curved surface. The method for manufacturing an organic light-emitting diode according to claim 3, wherein the specific curved surface constituting the plurality of convex portions has at least one recurved portion, and among the recurved portions, the closest to the flat surface 1 The closest distance from the curved portion to the flat surface is 1/10 or more of the average pitch of the plurality of convex portions. The method for manufacturing an organic light-emitting diode according to claim 1, wherein the plurality of convex portions form a honeycomb lattice, and the top of the plurality of convex portions is located to constitute the above in a plan view from a direction perpendicular to the flat surface The apex of the hexagon of the honeycomb lattice. The method for manufacturing an organic light emitting diode according to claim 5, wherein the convex portion at the vertex of the hexagon has a ridge portion between the convex portion at the vertex adjacent to the hexagon, and at least the ridge portion A part exists on the flat surface side of the convex portion connecting the ridge portion. The method for manufacturing an organic light emitting diode according to claim 6, wherein the height of the portion of the ridge portion closest to the flat surface is from the flat surface, and the height of the convex portion connecting the ridge portion from the flat surface is 50%~90%. An organic light-emitting diode, characterized in that it has a substrate, a transparent first electrode, an organic semiconductor layer including a light-emitting layer, and a second electrode, and the surface of the second electrode on the side of the organic semiconductor layer has a flat surface, And flat from above A plurality of convex portions protruding toward the base, the average pitch of the plurality of convex portions is 50 nm to 5 μm, the average aspect ratio of the plurality of convex portions is 0.01 to 1, and more than 80% of the plurality of convex portions have specific Curved surface, the specific curved surface is defined as any point where the specific curved surface is the first point, and the point that deviates from the first point toward the center point of the convex portion by only 1/10 of the average pitch When the second point is set, the inclination angle of the second tangent plane contacting the second point with respect to the first tangent plane contacting the first point is within 60°. The organic light emitting diode according to claim 8, wherein the area ratio of the flat surface in the surface of the second electrode on the side of the organic semiconductor layer is 5 to 50%.

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