TWI700847B - Metallic mold for manufacturing 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

Mold for manufacturing 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 its content is cited here.

The organic light-emitting diode system uses organic electroluminescence light-emitting elements. Organic light-emitting diodes generally have a configuration in which an anode and a cathode are respectively 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 necessary. 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 organic light emitting diodes is not necessarily sufficient. The light extraction efficiency is the ratio of the light energy emitted into the atmosphere from the light extraction surface (for example, the substrate surface in the case of the bottom emission type) relative to the light energy generated in the light-emitting layer. As one of the main reasons that reduce the light extraction efficiency, there is the influence of surface plasmon. In organic light-emitting diodes, the distance between the light-emitting layer and the metal cathode is relatively close. 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 and lighting with organic light-emitting diodes, and various methods for improvement are being studied. In order to improve the 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 plasmon into light, and the converted light is taken out of the device. In Patent Document 1, the two-dimensional lattice structure provided on the substrate can be reflected to obtain the two-dimensional lattice structure of the surface of the metal layer. Specifically, since the first electrode, the organic semiconductor layer including the light-emitting layer, and the second electrode are laminated on a substrate with a two-dimensional lattice structure, the surface on the light-emitting layer side of the second electrode reflects the same two as the substrate Dimensional lattice structure. Generally, the organic semiconductor layer and the first and second electrodes are formed by a vacuum film forming method using sputtering or vapor deposition. In contrast, Patent Document 2 discloses the formation of an organic semiconductor layer in an organic thin film solar cell by coating methods such as spin coating, inkjet, and slit coating. 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 Technical Literature] [Patent Literature] [Patent Document 1] International Publication No. 2012/60404 [Patent Document 2] International Publication No. 2014/208713

[The problem 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 the 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. The coating method uses a liquid-phase material during coating, so 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 of the substrate surface on the surface of the metal layer becomes lower. If the reflectivity of the shape is low, it is difficult to provide a desired shape required for taking out the surface plasmon on the second electrode. On the other hand, the use of coating to form an organic semiconductor layer has advantages such as a reduction in manufacturing cost associated with simplification of manufacturing equipment, and an increase in throughput due to shortening of vacuuming time. Therefore, there is a strong demand to use the coating method to form the organic semiconductor layer. Therefore, the inventors of the present invention adopt a method of sequentially carrying out the coating step, the stamping step of making the concave-convex shape, and the vacuum film forming step to make the organic light-emitting diode. In this method, first, in the coating step, at least a part of the organic semiconductor layer is formed by a coating method. Then, a mold having a shape opposite 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 a vacuum film forming method. This method has the advantage of reducing the processing cost of the substrate because there is no need to process the substrate. Since the number of layers produced by vacuum film formation can be reduced, it has the advantage of increasing the production yield. Because the vacuum is used after the uneven shape is formed The film forming method has the advantage that the desired uneven shape can be reflected on the second electrode. However, as a result of further research by the inventors, they found the following problem: 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 to the assumed luminous intensity . The present invention was completed in view of the above circumstances. The subject of the present invention is to provide a mold for producing an organic light-emitting diode exhibiting sufficient light-emitting characteristics even when a method combining a coating step, a compression molding step, and a vacuum film forming step is used. [Technical means to solve the problem] The inventors of the present invention conducted intensive research in order to solve the above-mentioned problems. As a result, it was found that by making the shape of the mold into a specific shape, the organic light-emitting diode can be made even when the coating step, the compression molding step, and the vacuum film forming step are combined to produce an organic light-emitting diode. Show sufficient luminous characteristics. 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, and any point of the specific curved surface of the above-mentioned specific curved surface is set as the first point, and only the deviation from the above-mentioned first point 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 in 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 above-mentioned specific curved surface may be connected in a manner that satisfies the conditions of the above-mentioned 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 part closest to the flat surface to the flat surface is 1/10 or more of the average pitch of the plurality of convex parts. (5) In the mold described in any one of (1) to (4) above, the plurality of protrusions may form a honeycomb lattice, and the plurality of protrusions may form a honeycomb lattice in a plan view from a direction perpendicular to the flat surface. The top of each convex part is located at the apex of the hexagon constituting the honeycomb lattice. (6) In the mold described in (5) above, the convex portion located at the apex of the hexagon may have a ridgeline portion between the convex portion located at the adjacent apex of the hexagon, and the ridgeline portion At least a part is present on the flat surface side relative to the convex portion connecting the ridge line portion. (7) In the mold described in (6) above, the height of the portion of the ridgeline portion closest to the flat surface from the flat surface may be relative to the height of the convex portion connecting the ridgeline portion from the flat surface It is 50% to 90%. (8) The method of manufacturing an organic light-emitting diode of one aspect of the present invention is to form a substrate with electrodes with a transparent first electrode on the substrate by a coating step followed by a vacuum film forming step Where the organic semiconductor layer including the light-emitting layer and the second electrode are formed on the surface of the first electrode, and between the coating step and the vacuum film forming step, there is a method such as any one of (1) to (7) above The press molding step in which the mold described in the above is pressed against the outermost surface of the coating layer formed in the coating step, and the shape of the main surface of the mold is formed on the outermost surface of the coating layer . (9) An organic light emitting diode of one 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 in this order, and the second electrode is on the side of the organic semiconductor layer The surface has a flat surface and a plurality of protrusions protruding from the flat surface toward the base, the average pitch of the plurality of protrusions is 50 nm to 5 μm, and the average aspect ratio of the plurality of protrusions is 0.01 to 1. More than 80% of the plurality of convex portions have a specific curved surface. For the specific curved surface, any point of the specific curved surface is set as the first point, and from the first point toward the center point of the convex portion When the point deviating only by 1/10 of the above average pitch is set as the second point, the inclination angle of the second tangent plane that contacts the second point with respect to the first tangent plane that contacts the first point is 60° Within. (10) In the organic light emitting diode described in (9), the area ratio of the flat surface of the surface on the organic semiconductor layer side of the second electrode may be 5 to 50%. [Effects of Invention] Even when the mold of one aspect of the present invention combines the coating step, the compression molding step, and the vacuum film forming step to produce an organic light-emitting diode, the organic light-emitting diode can exhibit sufficient light-emitting characteristics. The organic light-emitting diode of one aspect of the present invention has the desired light-emitting characteristics, and can efficiently extract the generated surface plasmon. The method for manufacturing an organic light-emitting diode according to one aspect of the present invention can produce an organic light-emitting diode capable of efficiently taking out surface plasmon 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 configuration will be described using drawings. The drawings used in the following description may be enlarged and shown as part of the feature for easy understanding of the feature and convenience, and the size ratio of each component may not be the same as the actual situation. The materials, dimensions, etc. exemplified in the following description are just examples, and the present invention is not limited to them, and can be implemented with appropriate changes within the scope not changing the gist. "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 portion among the plurality of convex portions 2a to 2n. In Fig. 1, if the center points of the adjacent convex portions are connected, a hexagonal shape in plan view is drawn, and a flat surface is arranged in the central area. The plurality of convex portions 2a to 2n are connected in a part. 2 is a cross-sectional view of a plane connecting the center point of the convex part of the mold and the center point of the flat surface in one aspect of the present invention. The section shown in Figure 2 is obtained in the form of AFM (Atomic Force Microscopy) images or microscope images obtained by observing the cut sample with an electron microscope. The AFM image is taken from the AFM image taken from a square area 30-40 times the average pitch P of the convex parts 2a-2n, and the center point 2An of the convex part 2n and the center point 1An of the flat surface 1n are taken out The profile information of the cut surface is obtained. The cross section is obtained by cutting the mold 10 through the cross section of the center point 2An of the convex portion 2n with FIB (Focused Ion Beam) or the like. 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 convex portion surface with a material that can withstand cutting or embed the convex portion with resin or the like to cut. In the case where either the section measured by AFM image or the section observed by microscope image can be obtained, the section measured by AFM image is preferred. The reason is that it is easy to obtain the measurement surface of a specific cut surface by the cross section measured by AFM image, and it is easy to confirm the shape of the cross section. When the convex portions 2a to 2n are regularly arranged, it is preferable to set the cutting direction for obtaining the cross section to be a 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 result of AFM. Specifically, a plurality of contour lines are drawn at 20 nm intervals for each convex portion 2a to 2n in parallel with the reference plane, and the center of gravity point of each contour line (the point determined by the x coordinate and the y coordinate) is obtained. The average position of each center of gravity point (position value determined by the average value of each x coordinate and the average value of y coordinate) is set as the center point 2Aa-2An of each convex portion 2a-2n. The reference surface is the measurement surface that has the slope corrected by the image information of 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, an inscribed circle inscribed in plan view is provided on each of the plurality of flat surfaces 1a to 1n. The center of the inscribed circle is set to the center points 1Aa to 1An of the flat surfaces 1a to 1n. The convex parts 2a-2n are parts protruding with respect to the flat surfaces 1a-1n. The so-called flat surfaces 1a to 1n refer to the area having a slope within ±5 ゜ with respect to the surface passing through the center of gravity of the area connecting the nearest convex portion and parallel to the reference plane of AFM. The convex portions 2a to 2n are arranged on one surface of the mold 10 two-dimensionally. The so-called "two-dimensional arrangement" refers to a state in which a plurality of protrusions are arranged on the same plane. The two-dimensional structure in which a plurality of convex portions are arranged two-dimensionally may be periodic or aperiodic. The mold 10 can be preferably used when the metal-containing electrode of the organic light emitting diode is made into a concave and convex shape. The uneven shape helps to take out the surface plasma generated on the electrode surface. When the organic light emitting diode made by the mold 10 emits light of a narrower frequency band, the two-dimensional arrangement of the plurality of convex portions is preferably periodic. As a preferable example of the periodic two-dimensional structure, the alignment direction of the straight line connecting adjacent convex portions is two directions and the crossing angle is 90° (square lattice), and the adjacent convex portions The alignment directions of the connected straight lines are 3 directions and the crossing angle is 120° (hexagonal lattice, honeycomb lattice), etc. The so-called "positional relationship with a crossing angle of 120°" specifically refers to a relationship that satisfies the following conditions. First, draw a line segment L1 with a length equal to the average pitch P in the direction from one center point 2Aa to the adjacent center point 2Ab. Then, from the center point 2Aa in the direction of 120° with respect to the line segment L1, draw a line segment L2 with a length equal to the average pitch P. If the center point adjacent to the center point 2Aa is within 15% of the average pitch P from the end points of the line segments L1 on the opposite side to the center point 2Aa, the intersection angle is in a positional relationship of 120°. The positional relationship where the crossing angle is 90 degrees is defined by replacing the above-mentioned "120°" with "90°". If the convex portions 2a to 2n are periodically arranged so as to satisfy 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 is increased, 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 vertices of the hexagon when viewed from a direction perpendicular to the flat surfaces 1a to 1n. In contrast, when the organic light-emitting diode produced by using the mold 10 emits light in a wider frequency band or light in a plurality of different frequency bands, it is preferably the two-dimensionality of the plurality of convex portions 2a to 2n The configuration is acyclic. The so-called "aperiodic arrangement" refers to a state in which the spacing and arrangement direction between the centers of the convex portions 2a to 2n are not fixed. Here, the average pitch P is the distance between adjacent convex portions, and can be specifically obtained as follows. Here, the adjacent convex portion refers to the case of the convex portion that is adjacent to each other without a flat surface in FIG. 1. First, in the randomly selected area on the main surface 10A of the mold 10, an AFM image is obtained for a square area whose one side is 30-40 times the average pitch P. For example, when the design distance is about 300 nm, an image of an area of 9 μm×9 μm～12 μm×12 μm is obtained. Furthermore, the distance between the adjacent portions of each convex portion in the obtained area is measured, and the measured distance between the adjacent portions is averaged, thereby obtaining the average pitch P _{1 in the area} . This process is performed similarly to randomly selected regions of the same area with a total of 25 or more places, and the average pitch P ₁ to P _{25 in} each region is obtained. The average value of the average pitch P ₁ to P _{25 in} the area of more than 25 locations 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 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, the surface plasma can be efficiently taken out from the metal electrode. The convex portions 2a-2n are formed with Ca-Cn in each area with a periodic structure. As a macroscopic whole, each region Ca-Cn can also be a non-periodic structure. The regions Ca to Cn shown in FIG. 3 are arranged in a positional relationship such that the intersection angle of the center point of each convex portion with respect to the center point of the flat surface is 120°. In FIG. 3, for convenience, the position of the center point of each convex portion 2a to 2n is represented by a circle u centered on the center point. The mode area Q of each area Ca to Cn (the mode value of each area area) is preferably in the following range. When the average pitch P is less than 500 nm, the mode area Q within 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 mode area Q within 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 mode 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 mode area Q is within a better range, the periodic structure macroscopically becomes a polycrystal with random lattice orientation. Therefore, when the surface plasmon is converted into propagating light and radiated on the metal surface, it can be suppressed in the plane The emission angle of the directional radiant light becomes random, so that the luminous light taken out from the device has anisotropy. As shown in Fig. 3, the areas, shapes, and lattice orientations of the regions Ca to Cn are random. 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 line of a region, 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 within 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 within 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 emission angle of the surface plasma 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 all directions opposite sex. The degree of randomness of the shapes of the respective regions Ca to Cn is specifically, the ratio of a to b and the standard deviation of a/b in the formula (1) are preferably 0.1 or more. Specifically, the randomness of the lattice orientation of each region Ca to Cn preferably satisfies the following conditions. First, draw a straight line K0 that connects the center points of any two adjacent convex portions in any area (I). Next, select one area (II) adjacent to the area (I), and draw three lines connecting any convex portion in the area (II) with the center points of the three convex portions adjacent to the convex portion Straight line K1～K3. When the straight lines K1 to K3 have an angle of 3 degrees or more with respect to the 6 straight lines that are rotated 60° per rotation with the straight line K0 as a reference, it is defined that the lattice orientations of the region (I) and the region (II) are different. In the region adjacent to the region (I), there are preferably more than 2 regions, preferably more than 3 regions, and more preferably 5 or more regions having different crystal lattice orientations from the region (I) . At this time, the convex portion-based lattice squares are aligned in the respective regions Ca to Cn, but macroscopically, they are non-uniform polycrystalline structures. The randomness of the macroscopic lattice orientation can be evaluated by the ratio of the maximum value and the minimum value of the fundamental wave of 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, obtain its 2D Fourier transform image, draw the circle of the wave number from the origin away from the fundamental wave, 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 when the maximum value and minimum value of the FFT fundamental wave are relatively large, the crystal lattice orientation of the convex part is the same, and when the convex part is regarded as a two-dimensional crystal, it is a structure with higher single crystal properties. On the contrary, it can be considered that when the ratio between the maximum value and the minimum value of the FFT fundamental wave is small, the lattice orientation of the convex part is not consistent, and when the convex part is regarded as a two-dimensional crystal, it is 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 so-called 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 less than 0.01, in the organic light emitting diode produced by using the mold 10, the effect of taking out the surface plasmon as radiant light cannot be sufficiently obtained. On the other hand, if the average aspect ratio is 1 or more, it is difficult to form the convex part with the following specific curved surface. In addition, it is difficult to transfer the shape of 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 is obtained at one area of 25 μm ² (5 μm×5 μm) randomly selected on 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 part refers to the distance from the flat surface 1a to 1n to the top of the convex part, and the width of the convex part refers to the diameter of the inscribed circle with the center point of the convex part as the center when viewed from above. Then, find the average value of the height and width of the convex part in the area. Perform the same treatment for a total of 25 areas randomly selected. Then, the obtained average value of the height and width of the convex portion of each area at 25 locations is then 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 a specific curved surface. The ratio of the convex portions having the specific curved surface among the plurality of convex portions is more preferably 90% or more, and more preferably 95% or more. The specific curved surface is defined as follows. Fig. 4 is a schematic cross-sectional view in which the mold is cut at any cross section passing through the center point of the convex portion, and one of the convex portions is enlarged. 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 a 1st tangent plane t1. In addition, a point deviated from the first point p1 toward the center point 2An of the convex portion 2n by only 1/10 of the average pitch is referred to as the second point p2. Here, the term “deviated by only 1/10 of the average pitch” refers to the distance L moving parallel to the flat surface 1 from the first point p1 toward the center point 2An. Let the tangent plane with respect to this 2nd point p2 be a 2nd tangent plane t2. At this time, the inclination angle of the second tangent plane t2 with respect to the first tangent plane t1 is set to θ. Even in any part of the curved surface 2B of the convex portion 2n, when the inclination angle θ of the second tangent plane t2 with respect to the first tangent plane t1 is within 60°, the convex portion 2n can be regarded as a specific Curved surface. The inclination angle θ is preferably within 45°, and more preferably within 30°. Fig. 5 is a schematic cross-sectional view when a mold of one aspect of the present invention is pressed against the surface of a 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 layered body 20, the convex portions 2a to 2n of the mold 10 are pressed against the layered body 20 at first. 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. With this 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 layered body 20 is deformed and becomes a shape corresponding to the mold 10. The force F1 applied to each layer of the layered 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 uniformly spreads in the in-plane direction. Therefore, the thickness of each can be prevented from becoming extremely thin. Moreover, generally speaking, the boundary portion 3 between the plurality of convex portions 2a to 2n and the flat surface of the mold 10, which is a part prone to voids, is also sufficiently supplied with the material of each layer along the specific curved surface 2B. That is, it is also possible to prevent the generation of voids in the boundary portion 3. In contrast, FIG. 6 is a schematic cross-sectional view when a mold without a specific curved surface is pressed against the surface of a laminate formed by coating. The convex part 152n of the mold 15 shown in FIG. 6 has the corner part 155 whose shape changes rapidly. The tangent plane of the corner portion 155 separated by two points of the corner portion 155 does not satisfy the relationship of a specific curved surface. Therefore, the force F2 applied to each layer constituting the layered body 20 is not uniformly dispersed along the shape of the convex portion 152n, and the stress concentrates in the vicinity of the corner portion 155. As a result, each of the first layer 21, the second layer 22, and the third layer 23 cannot spread 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 portion 153 between the convex portion 152n and the flat surface, and voids are likely to occur. The layer constituting the laminated body 20 corresponds to any layer constituting the organic light emitting diode. If part of each layer constituting the organic light-emitting diode is cut off, a problem arises that the cut part of the organic light-emitting diode does not emit light, or does not exhibit sufficient light-emitting characteristics. That is, by using the mold 10 of this embodiment, the problem that the organic light emitting diode does not emit light or does not exhibit sufficient light emitting characteristics can be avoided. Returning to FIG. 5, in order to avoid a gap between the mold 10 and the laminated body 20, it is preferable that the boundary part 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 to satisfy the tangent plane at a point deviated from 1/10 of the average pitch from any one point with respect to the tangent at any one point The angle of inclination of the plane is within 60°. Fig. 7 is a schematic cross-sectional view when a mold of another aspect of the present invention is pressed against the surface of a laminate formed by coating. The mold 30 shown in FIG. 7 has a plurality of convex portions and a flat surface 31, and the boundary portion 33 between the plurality of convex portions and the flat surface 31 is connected by a specific curved surface. That is, in the connecting portion between the flat surface 31 and the convex portion 32n, it is also satisfied that the inclination angle of the tangent plane at the point deviated from 1/10 of the average pitch from any one point to the tangent plane at any one point is within 60° The relationship. That is, the boundary 33 becomes gentle. If the mold 30 shown in FIG. 7 is pressed against the laminated body 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 does not concentrate. Therefore, the materials constituting each layer spread smoothly along the main surface of the mold 30. As a result, the generation of voids between the mold 10 and the laminated body 20 can be avoided, and the thickness of each layer of the laminated body 20 can be made uniform in the in-plane direction. In the mold 30, the boundary portion 33 between the flat surface 31 and the plurality of convex portions is made gentle, and it is possible to simultaneously satisfy that the specific curved portion constituting the convex portion has at least one recurved portion p _in and the recurved portion p _in the outermost side of the flat surface 31 of the first inflection portion p1 _in a curved surface connecting the flat surface 31 of the downwardly convex achieved. 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 inflection 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 so-called closest distance refers to the distance between the narrowest part of the width between the first inflection portion p1 _1n and the flat surface 31 in the plan view of the convex portion 32n. If the closest distance from the first curved 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 more gentle. In addition, if the boundary 33 of the mold 30 is made gentle, when a layer is formed by the vacuum film forming method on the transfer object made using the mold 30, the layer formed by the vacuum film forming method reflects the shape of the transfer object 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 23A of the curved surface 20A formed on the outermost surface of the laminated body 20 using the mold 30 is also gentle. Generally speaking, the part where the shape changes rapidly is a large change in the dispersion of film-forming particles during vacuum film formation. In contrast, 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-based laminate 20 shown in FIG. 8 is relatively gentle. Therefore, the outer surface 26B of the vacuum-formed layer 26 can fully reflect the shape of the main surface 20A. Here, the so-called "sufficiently reflected" means that it is not necessary to completely reflect the shape formed in the molding step. If the average pitch of the convex portions forming the outer surface 26B of the vacuum-formed layer 26 is within ±10% compared to the average pitch of the convex portions forming the main surface 20A, and the outer surface of the vacuum-formed layer 26 is formed When the average height of the protrusions of 26B is within ±10% of the average height of the protrusions constituting the main surface 20A, it can be said that the outer surface 26B of the vacuum-formed layer 26 fully reflects the shape of the main surface 20A. For the measurement of the average distance mentioned here, the above-mentioned measurement method of the average distance P can be applied. In addition, the average height can be measured using the above-mentioned average height H measurement method. When the layer 26 to be vacuum-formed is an electrode, it does not need to be a shape in which the outer surface 26B fully reflects 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 scanning electron microscope (SEM) or a transmission electron microscope (TEM) can be used for cross-sectional observation, or after removing the layer covering the observation surface by three-dimensional The method of observation 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 5-50%, more preferably 5%-30%. If the area ratio of the flat surfaces 1a to 1n in the main surface 10A is 5% or more, in the organic light emitting diode manufactured using the mold, the aspect ratio of the unevenness of the surface plasma can be reduced. 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 the mold, it is possible to prevent surface plasma from being trapped by the flat surface. Fig. 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 cut in a plane connecting the center points of adjacent convex portions in FIG. 1. The dotted line in FIG. 9 is an approximate curve of the convex portions 2a to 2n. The approximate curve can be obtained by approximating the center points 2Aa to 2An of the convex portions 2a to 2n as vertices to a normal distribution. 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 of the more approximate curve closer to the center points 2Aa to 2An are convex portions 2a to 2n, and the opposite side thereof is the ridge portion 4. It is preferable that the connection part of the ridgeline part 4 and the convex parts 2a-2n, and the connection part of the ridgeline part 4 and the flat surface 1a-1n are connected in the manner that satisfies the condition of the specific curved surface. By connecting these connecting portions so as to satisfy the condition of a specific curved surface, the force generated when the mold 10 is pressed against the laminate can be more uniformly dispersed. In other words, it is possible to prevent the layers constituting the laminate against which the mold 10 is pressed from being cut. Moreover, as shown in FIG. 9, it is preferable that at least a part of the ridgeline part 4 exists on the flat surface 1n side rather than the convex part 2n which connects the ridgeline part 4. That is, it is preferable that the height h of the portion closest to the flat surface 1n of the ridge portion 4 from the flat surface 1n is lower than the height H of the convex portion 2n connecting the ridge portion 4 from the flat surface 1n. Fig. 13 is a plan view of the main part of the mold of this embodiment from a 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 object to be transferred, the air between the mold and the object to be transferred is removed through this portion (Figure 13 arrow). In other words, it is possible to prevent air from entering the object to be transferred, so that uniform transfer can be performed. Also, as shown in FIG. 13, in a plan view from a direction perpendicular to the flat surface 1n, the tops of the plurality of protrusions 2a to 2n are located at the vertices of the hexagons constituting the honeycomb lattice (hexagonal lattice) When the mold is pressed against the transfer object, the diffusion of the resin or the like becomes equal, and the pressure can be evenly applied to the transfer object. If the pressure can be applied uniformly, for example, even when the object to be transferred is a thin layer, the layer can be prevented from being cut or the layer thickness becomes extremely thin. Moreover, the height h of the portion closest to the flat surface 1n of the ridge portion 4 shown in FIG. 9 from the flat surface 1n is preferably relative to the height H of the convex portion 2n connecting the ridge portion 4 from the flat surface 1n 50%～90%, more preferably 60～85%. 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 the air decreases. So far, one embodiment of the present invention has been described with the mold 10 of FIG. 1 as an example, but the shape of the mold is not limited to this configuration. Fig. 10 is a three-dimensional schematic diagram of a mold of another aspect of the present invention. The mold 40 shown in FIG. 10 is different from the mold 10 and the like in that the convex portions 42a to 42n are spaced apart from each other and include one flat surface 41. In addition, for example, the structure shown in FIG. 11 may be adopted. Fig. 11 is a three-dimensional schematic diagram of a mold of another aspect 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 inverted in the positional relationship between the convex portion and the flat surface. That is, in the mold 50, the plurality of convex portions 52a to 52n are arranged in an area surrounded by the most adjacent flat surface among the plurality of flat surfaces 51a to 51n. In Fig. 11, if the center points of the adjacent flat surfaces are connected, a hexagonal shape is drawn in a plan view, and a convex portion is arranged in the central area. Even when the positional relationship between the plurality of convex portions 52a to 52n and the flat surfaces 51a to 51n is reversed as in the mold 50, each convex portion 52a to 52n is formed by a specific curved surface, so it is pressed against the mold 50 It is possible to prevent the layers constituting the laminate from being cut during the press molding step. A mold of one aspect of the present invention has a convex portion, and the convex portion has a specific curved surface. Therefore, the organic light emitting diode manufactured by using the mold 10 does not have a thinner part or a part 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 processing, laser lithography, laser thermal lithography, interference exposure, reduced exposure, aluminum anodization, and particle masking methods. form. Among them, it is preferable to use a method of using a particle mask to make the mold. The method of using a particle mask refers to a method of performing an etching process after forming a particle monolayer film on the flat surface of the mold base material as an etching mask. In the method of using the particle mask, the base material directly below the particle is not etched and becomes a convex part. Hereinafter, a specific example of the method of using the particle mask will be described. Fig. 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 substrate 61 (FIG. 14(a)). The method of forming the single-particle film etching mask 62 on the substrate 61 can be, for example, a method using a so-called LB method (Langmuir-Blodgett method). Specifically, the method of forming the single-particle film etching mask 62 includes: a dropping step, which drops a dispersion liquid in which particles are dispersed in a solvent onto the liquid surface in a water tank; and a single-particle film formation step, which uses The single particle film F containing particles is formed by volatilizing the solvent; and the migration step of removing the single particle film F onto the substrate. Each step will be described in detail below. (Dropping step and single particle film formation step) First, add more than one hydrophobic organic solvent among the more volatile solvents such as chloroform, methanol, ethanol, methyl ethyl ketone, and add the surface to be hydrophobic To prepare a dispersion liquid. In addition, a water tank (tank) V is prepared as shown in FIG. 15, and water W is added as a liquid for spreading particles on the liquid surface (hereinafter, also referred to as lower water). Then, the dispersion liquid is dropped to the liquid surface of the lower layer of water (dropping step). Then, the solvent as the dispersion medium volatilizes, and the particles spread out in a single layer on the liquid surface of the lower layer of water to form a two-dimensionally densest packed single particle film F (single particle film forming step). In this way, when selecting hydrophobic particles as particles, hydrophobic ones must also be selected as solvents. On the other hand, in this case, the lower layer water must be hydrophilic, and generally, water is used as described above. With such a combination, self-assembly of particles is promoted as follows to form a two-dimensionally densest packed single-particle film F. However, hydrophilic particles and solvents can also be selected. In this case, a hydrophobic liquid is selected as the lower layer water. (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 then transferred to the substrate 61 as the etching target while maintaining the single layer state (transition step). The base 61 may be planar, or may include a non-planar shape such as a curved surface, an inclination, and a level difference in part or all. The single particle film F can cover 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 removing the single particle film F onto the base 61 is not particularly limited. For example, as the first method, it is also possible to keep the water-based substrate 61 substantially parallel to the single-particle film F while dropping from above to contact the single-particle film F. The single-particle The affinity between the film F and the substrate 61 causes the single-particle film F to move and be transferred to the substrate 61. In addition, as a second method, the substrate 61 may be arranged in a substantially horizontal direction in the lower layer of the water tank before the single particle film F is formed. After the single particle film F is formed on the liquid surface, the liquid level is gradually lowered, thereby reducing The single particle film F is transferred to the base 61. According to these methods, the single particle film F can be transferred to the substrate 61 without using a special device. Even if it is a single-particle film F with a larger area, it can easily maintain its second densest filling state and be transferred to the substrate 1. In this respect, it is preferable to adopt the so-called LB groove method. By this migration step, a plurality of particles M are arranged in a substantially single layer on one surface of the substrate 61, that is, the flat surface 61a. 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 the vapor phase etching is started, first, as shown in FIG. 14(b), the etching gas passes through the gaps of the particles M constituting the etching mask 62 to reach the surface of the substrate 61, and a groove is formed in this portion. Then, a column 63 appears at a position corresponding to each particle M, respectively. Between the columns 63, grooves 61m are formed. The groove portion 61m is formed at the center of the three particles M arranged on the equilateral triangle by the densest filling. Therefore, the groove portion 61m is located at the apex of the regular hexagon with the column 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 silica particles, etc. can be used. In addition, the etching gas can be a gas commonly 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 and so on. The particles M and the etching gas can be changed according to the substrate 61 to be etched. For example, when gold particles are selected as the particles M constituting the single-particle film etching mask 62, and the glass substrate is selected as the substrate 61 and these are combined, if the etching gas uses CF ₄ , CHF _3, etc. and glass If it is reactive, the etching speed of gold particles becomes relatively slow, and the glass substrate is selectively etched. The molds of various shapes as shown in Fig. 1, Fig. 10 and Fig. 11 can obtain the desired shape by changing the dry etching conditions. Moreover, in order to make the surface shape of the convex part more gentle, it is also possible to use wet etching together. The conditions of dry etching include the material of the particles constituting the particle mask, the material of the original plate, the type of etching gas, bias power, power supply power, gas flow and pressure, etching time, etc. 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 like 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 parts can be freely changed by changing the particle diameter of the particles used. In addition, when a particle monolayer film is used to form a non-periodic structure, it can be produced by using a plurality of particles with different particle diameters. (Odd-number transfer step) Next, the substrate 61 shown in FIG. 14(b) is subjected to odd-number transfer. The transfer body 71 shown in FIG. 14(c) is obtained by the odd number of transfers. Specifically, first, the produced base 61 is transferred with resin. The surface of the obtained resin transfer product is coated with metal plating such as Ni by electroforming or the like. The hardness of the transfer body 71 is increased by plating with a metal coating, so that the following shape adjustment and the like can be performed. Since the top of the cylinder 63 of the base 61 is covered by the particles M, it is a flat surface. Therefore, a flat surface 71 n is formed in the transfer body 71 at a position corresponding to the cylinder 63 of the base body 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 body 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 are cases where a specific curved surface is not formed on the surface of the transfer body 71. For example, there is a case where a corner portion 72a is 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, and the outer surface of the convex portion 72n is a specific curved surface. Further etching can be performed by wet etching or dry etching. Hereinafter, the case of dry etching will be specifically described. In order to remove the corner 72a, as shown in FIG. 14(d), the transfer body 71 is irradiated with the plasma P generated by the plasma etching device to perform physical etching. The physical etching is different from the reactive etching used in the etching step. Reactive etching advances the etching by reacting plasma chemical species with the transfer body 71. In contrast, the physical etching is performed by the physical force that collides with the transfer body 71 between the plasma chemical species. Therefore, the physical etching is due to the unevenness of the etching rate between the part with a higher probability of chemical species conflict and the part with a lower probability of plasmaization. Compared with reactive etching, it has etching anisotropy. The physical etching is similar to the ashing treatment. In a plasma etching device, a plasma chemical species is used between the upper electrode and the lower electrode. Specifically, the low-potential lower electrode is electrically connected to the transfer body 71 to charge the transfer body 71. The chemical species plasma-ized between the upper electrode and the lower electrode are attracted by the transfer body 71 of low potential and collide with the transfer body 71 at a high speed. At this time, it has the property that if there is a sharp portion like the corner portion 72a in the charged transfer body 71, the charge is concentrated in the portion. Therefore, most of the plasma chemical species are attracted by the sharp part. That is, the sharp part is more likely to conflict 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 the convex portion 2n having a specific curved surface (FIG. 14(e)). As the etching gas used for physical etching, for example, rare gas such as argon, oxygen, etc. can be used. These gases lack reactivity and promote physical etching. In addition, as an etching gas used 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 a way that the etching using physical conflict becomes more significant than the chemical reactivity of the ion species. For example, the etching conditions can be 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 that of reactive etching. Preferably, the physical etching is performed using argon or oxygen under low pressure and high bias. The specific conditions are different depending on the device, so it cannot be determined 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 of the bias. Even when other dry etching gases are used, they will not greatly deviate from the above range, but it is preferable to shorten the processing time. The reason is that the etching speed is relatively fast, and the corner portion 62a is etched as expected. So far, only the corner portion 72a has been mentioned. For example, there are also cases where a sharp portion is formed in the ridge portion (refer to FIGS. 1 and 9) between the adjacent convex portions 72n. Even in this case, the sharp portion of the ridge portion can be removed simultaneously with the corner portion 72a by physical etching. (Reproduction Step) The mold made by the above method can be used directly as a mold, or a replica made with the made mold as the original plate can be used as a real-time mold. The copy can be made by transferring the made mold an even number of times. Specifically, first, the produced mold is transferred with resin. The surface of the obtained odd-numbered transfer body is coated with metal plating such as Ni by electroforming. The hardness of the odd-numbered transfer body can be increased by plating with the metal, and 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 becomes the same shape as the manufactured mold. Finally, the surface of the even-numbered transfer body is plated with metals such as Ni by electroforming or the like to complete the replication of the mold. In addition, the mold 30 in which the plurality of convex portions 32n and the boundary portion 33 of the flat surface 31 shown in FIG. 7 are also connected by a specific curved surface can be manufactured 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-numbered transfer step. By performing physical etching between the etching step and the odd-numbered transfer step, the top of the cylinder 63 becomes gentle, and the shape of the concave portion of the transfer body 71n becomes gentle. Furthermore, 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 convex part after the transfer can be made gentle. "Organic Light Emitting Diode" FIG. 12 is a schematic cross-sectional view of an organic light emitting diode device 100 according to an aspect of the present invention. The organic light emitting diode device 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. In addition to the light-emitting layer 133, the organic semiconductor layer 130 shown in FIG. 12 also has a hole injection layer 131 and a hole transport layer 132 between the first electrode 120 and 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 therebetween. 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 necessarily provided, and may not be provided. The organic light emitting diode device 100 of the present invention may be further provided with other layers within a range that does not impair the effects of the present invention. The first electrode 120 and the second electrode 140 of the organic light emitting diode apply 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 these are coupled to generate light. The generated light directly passes through the first electrode 120 and is taken out to the outside of the device, or is taken out to the outside of the device after being reflected by the second electrode 140 once. The second electrode 140 has a two-dimensional structure in which a plurality of protrusions 142a to 142n are two-dimensionally arranged on the surface 140A on the light-emitting layer 133 side. The two-dimensional structure is the same as the above-mentioned mold, which can be either periodic or non-periodic. The average pitch of the plurality of protrusions 142a to 142n is 50 nm to 5 μm, preferably 50 nm to 500 nm. The average pitch can be calculated using the same method as the average pitch in the mold. If the average pitch of the protrusions 142a to 142n is within this range, the energy captured in the form of surface plasmon on the surface 140A of the second electrode as the metal electrode can be efficiently radiated, which can be taken out 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 on 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 and can be taken out as light. The capture of surface plasmon is produced in the following process. When the light-emitting layer 133 emits light from the light-emitting molecules, near-field light is generated very close to 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 plasmon on the metal surface is the one in which the sparse and dense waves of free electrons generated by incident electromagnetic waves (near-field light, etc.) accompany the surface electromagnetic field. In the case of surface plasmon on a flat metal surface, the dispersion curve of the surface plasmon and the dispersion line of light (spatially propagating light) do not cross. Therefore, the energy of the surface plasmon cannot be extracted as light. In contrast, if the metal surface has a two-dimensional periodic structure, the dispersion curve of the surface plasmon that is diffracted by the two-dimensional periodic structure crosses the dispersion curve of the spatially propagating light. As a result, the energy of the surface plasmon can be extracted to the outside of the device as radiant light. In this way, if a two-dimensional periodic structure is provided, the energy of light lost in the form of surface plasmon is taken out. The extracted energy is radiated from the surface of the second electrode 140 as spatially propagating light. At this time, the directivity of the light radiated from the second electrode 140 is relatively high, and most of it faces the extraction surface. Therefore, high-intensity light is emitted from the extraction surface, and the extraction efficiency is improved. More than 80% of the plurality of convex portions 142a to 142n have a specific curved surface. The specific curved surface is defined the same as the specific curved surface in the mold. On the surface 140A of the second electrode, a flat surface 141 is formed between the plurality of convex portions 142a to 142n. 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 unevenness for taking out the surface plasma 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 plasmon 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 large negative value of the real part of the complex permittivity, and it is preferable to select a metal material with a higher plasma frequency that is advantageous for the extraction of surface plasma . As the material, for example, a single substance such as gold, silver, copper, aluminum, and magnesium, an alloy of gold and silver, and an alloy of silver and copper can be cited. Considering the light extraction of the organic light emitting diode, it is preferable to use a metal material having a resonance frequency in the entire visible light region, and it is particularly preferable to use 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 will be lower and the front brightness will decrease. If it is thicker than 500 nm, damage caused by heat or radiation during film formation, and mechanical damage caused by film stress will accumulate in the organic light-emitting layer. 133, etc., including organic layers. The organic semiconductor layer 130 contains an organic material. In FIG. 12, 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 are formed with uneven shapes. 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 in the method of manufacturing an organic light emitting diode below, and the concavo-convex shape only needs to be formed on the surface of the second electrode 140 side of any layer constituting the organic semiconductor layer. Compared with the layer formed with the uneven shape, the layer on the second electrode 140 side has a shape that all reflects the uneven shape. The light emitting layer 133 includes an organic light emitting material. Examples of organic light-emitting materials include tris[1-phenylisoquinoline-C2,N]iridium(III)(Ir(piq)3), 1,4-bis[4-(N,N-diphenylamino) Styrylbenzene)] (DPAVB), bis[2-(2-benzoxazolyl)phenol] zinc (II) (ZnPBO) and other pigment compounds. In addition, a fluorescent dye compound or phosphorescent material doped with another substance (host material) can also be used. In this case, examples of the host material include hole transport materials, electron transport materials, and the like. As the 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. For example, as the material (hole injection material) constituting the hole injection layer 131, for example, 4,4',4''-tris[2-naphthylphenylamino]triphenylamine (2-TNATA), etc. Compound etc. As the material (hole transport material) constituting the hole transport layer 132, for example, 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 aromatics 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.

Diazole-based compounds, metal complex-based compounds such as tris(8-quinolino) aluminum (Alq), etc. The overall thickness of the organic semiconductor layer including the light-emitting layer 133 is usually 30 to 500 nm. The first electrode 120 uses a transparent conductor that transmits visible light. The transparent conductor constituting the first electrode 120 is not particularly limited, and known ones can be used as the transparent conductive material. For example, Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Zinc Oxide (ZnO), Zinc Tin Oxide (ZTO), etc. can be cited . The thickness of the first electrode 120 is usually 50 to 500 nm. The base 110 uses a transparent body that transmits visible light. As the material constituting the base 110, it may be an inorganic material or an organic material, or a combination thereof. As an inorganic material, various glass, such as quartz glass, an alkali-free glass, white board glass, transparent inorganic minerals, such as mica, etc. are mentioned, for example. Examples of the organic material include resin films such as cycloolefin-based films and polyester-based films, and fiber-reinforced plastic materials in which fine fibers such as cellulose nanofibers are mixed in the resin film. Although it depends on the application, in general, the substrate 110 uses a material with a higher visible light transmittance. The following is used, that is, the transmittance in the visible light range (wavelength 380 nm to 800 nm) does not impart a bias in the spectrum and the transmittance is 70% or more, preferably 80% or more, 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 meter, AFM, etc. "Method of Manufacturing Organic Light-Emitting Diode" One aspect of the method of manufacturing an organic light-emitting diode of the present invention is to have a transparent first electrode on the surface of a substrate with electrodes on which the first electrode is formed. A method of manufacturing an organic light-emitting diode including an organic semiconductor layer of a light-emitting layer and a second electrode by a coating step and a subsequent vacuum film forming step. Between the coating step and the vacuum film forming step, the mold is pressed against the outermost surface of the coating layer formed in the coating step, and the outermost surface of the coating layer forms the shape of the main surface of the mold Reverse the molding step of the shape. <Preparation steps of the substrate with electrodes> The substrate with electrodes forms a transparent first electrode on the transparent substrate. The above-mentioned ones can be used for the substrate and the first electrode. The method of forming the first electrode on the substrate can use a known method. 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, some 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 solution must be selected so as not to penetrate the layers that have been formed into the film until the previous step. Therefore, the more the number of layers formed by coating increases, the more difficult it is to select an appropriate one Solvent. Therefore, in the coating step, it is preferable to form up to the light-emitting layer in the layer constituting the organic semiconductor layer. A known method can be used for the coating method, and for example, spin coating, bar coating, slit coating, die nozzle coating, spray coating, inkjet method, etc. can be used. The coating method does not require a vacuum during the lamination process, and does not require large-scale equipment. In addition, since there is no time required for vacuuming, etc., the throughput of manufacturing organic light-emitting diodes can be increased. <Stamping step> The stamping step is a method of forming a concave and convex shape by a so-called imprinting 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 its shape, it maintains its shape even after the mold is removed. In addition, even after the coating solution is dried and evaporated, when the material forming the film-forming layer has a glass transition point, it can be shaped by pressing the film-forming layer against the mold while it is heated to above the glass transition point . In the compression molding 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 on the second electrode 140 side of the light-emitting layer 133 to transfer the reverse shape of the mold. As described above, the mold of one aspect of the present invention has a plurality of convex parts and a flat surface, and the plurality of convex parts 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 the specified curved surface. As a result, it is possible to avoid a situation in which the thickness of the light-emitting layer 133 becomes extremely thin or a situation in which the light-emitting layer 133 is cut. <Vacuum film forming step> In the vacuum film forming step, a layer that is not formed in the coating step and the second electrode among the layers constituting the organic semiconductor layer are formed by a vacuum film forming method. As the vacuum film forming method, a vacuum vapor deposition method, a sputtering method, CVD (chemical vapor deposition, chemical vapor deposition), etc. 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 forming method. Compared with the coating method, the vacuum film forming method has higher reflectivity to reflect the shape of the substrate. Therefore, the shape of the convex portion and the flat surface formed on the outermost layer of the coating layer in the compression molding step is also reflected in the layer laminated on the uppermost layer of the outermost layer of the coating layer. In the concave portion formed in the outermost layer of the coating layer by pressing against the mold, it is preferable that the concave portion and the flat surface are connected by a specific curved surface. That is, it is preferable that the boundary between the concave portion and the flat surface is gentle. The uneven thickness of the layer formed by vacuum film formation can be further suppressed. Since the outermost layer of the coating layer forms the above-mentioned recesses and flat surfaces, the surface on the light-emitting layer side of the second electrode is formed in a shape reverse to the outermost layer of the coating layer as shown in FIG. 12. This shape reflects the shape of the mold pressed against in the pressing step. In the method for manufacturing an organic light emitting diode according to one aspect of the present invention, since there is a press molding step using a mold having a specific shape, the desired unevenness can be easily formed 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, thereby obtaining high light-emitting characteristics.

1a～1n: flat surface 1Aa～1An: center point 2a～2n: convex part 2Aa～2An: center point 2B: curved surface 3: junction part 4: ridge part 10: mold 10A: main surface 15: mold 20: laminated body 20A: curved surface 21: first layer 22: second layer 23: third layer 23A: junction 26: layer 26B: outer surface 30: mold 31: flat surface 32n: convex portion 33: junction 40: mold 41: Flat surface 42a to 42n: convex part 50: mold 51a to 51n: flat surface 52a to 52n: convex part 61: base 61m: groove part 62: single particle film etching mask 63: cylinder 71: transfer body 71n: flat surface 72a: corner part 72n: convex part 100: organic light-emitting diode 110: base 120: first 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: second electrode 140A: surface 141: flat surface 142a to 142n: convex portion 152n: convex portion 155: corner F1: force F2: force F3: force h: height H: average height K0, K1～ K3: straight line M: particle p1: first point p1 _in : first recurve p2: second point p _in : recurve P: average pitch P: plasma t1: first tangent plane t2: second tangent plane u: circle V: water tank (tank) W: water θ: tilt angle

Fig. 1 is a three-dimensional schematic diagram of a mold of one aspect of the present invention. Fig. 2 is a schematic cross-sectional view of a mold of one aspect of the present invention cut on a plane passing through the center point of a convex portion of the mold and the 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 on a plane passing through the center point of a convex portion formed on the mold, and is a cross-sectional view of an enlarged portion of a convex portion. Fig. 5 is a schematic cross-sectional view when a mold of one aspect of the present invention is pressed against the surface of a laminate formed by coating. Fig. 6 is a schematic cross-sectional view when a mold without a specific curved surface is pressed against the surface of a laminate formed by coating. Fig. 7 is a schematic cross-sectional view when a mold of another aspect of the present invention is pressed against the surface of a laminate formed by coating. 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. Fig. 9 is a schematic cross-sectional view cut along the adjacent convex portion of the mold of one aspect of the present invention. Fig. 10 is a three-dimensional schematic diagram of a mold of another aspect of the present invention. Fig. 11 is a three-dimensional schematic diagram of a mold of another aspect of the present invention. Fig. 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 plan view of the main part of the mold of this embodiment from a direction perpendicular to the flat surface. 14A to E are diagrams schematically showing the manufacturing method of the mold. 15A and B are diagrams schematically showing the dropping step and the single particle film forming step in the manufacturing process of the mold.

1a~1n: flat surface

1Aa~1An: center point

2a~2n: convex part

2Aa~2An: center point

10: Mould

10A: Main side

P: average pitch

Claims (6)

A mold for the manufacture of organic light-emitting diodes, which is used to extract the surface plasmon structure to give the electrodes of the organic light-emitting diodes, and has a flat surface and a plurality of protrusions on the main surface, the plurality of protrusions The average pitch is 50nm~500nm, the average aspect ratio of the plurality of protrusions is 0.01~1, more than 80% of the plurality of protrusions have a specific curved surface, and the specific curved surface is between the specific curved surface When an arbitrary point is set as the first point, and a point deviating from the first point by only 1/10 of the above average pitch is set as the second point, the second tangent plane contacting the second point is relative to the The inclination angle of the first tangent plane that the first point meets is within 60°, and the flat surface and the convex portion having the specific curved surface are connected to meet the conditions of the specific curved surface. The mold for manufacturing an organic light-emitting diode according to claim 1, wherein the area ratio of the above-mentioned flat surface in the above-mentioned main surface is 5-50%. The mold for manufacturing an organic light-emitting diode according to claim 1, wherein the specific curved surface constituting the plurality of convex portions has at least one curved portion, and the curved portion closest to the flat surface The closest distance from the first curved portion to the flat surface is 1/10 or more of the average pitch of the plurality of convex portions. The mold for manufacturing an organic light emitting diode according to claim 1, wherein the plurality of protrusions form a honeycomb lattice, and in a plan view from a direction perpendicular to the flat surface, the tops of the plurality of protrusions are located The vertices of the hexagon of the honeycomb lattice. The mold for manufacturing an organic light emitting diode according to claim 4, wherein the convex portion located at the apex of the hexagon has a ridge line portion between the convex portion located at the apex adjacent to the hexagon, and the ridge portion is At least a part is present on the flat surface side relative to the convex portion connecting the ridge line portion. The mold for manufacturing an organic light emitting diode according to claim 5, wherein the height of the portion of the ridgeline portion closest to the flat surface from the flat surface is relative to the height of the convex portion connecting the ridgeline portion from the flat surface It is 50%~90%.

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