200911019 九、發明說明： * 【發明所屬之技術領域】 ‘ 本發明提供一種有機發光二極體結構，尤指一種具有 凹面鏡（concave mirror)結構之有機發光二極體以提昇光 利用率。 【先前技術】 在平面顯示器中’有機發光二極體(〇rganic Hght emitting diode，OLED)顯示器雖然起步較晚，然而卻以具備 自發光、廣視角、回應速度快、低耗電量、對比強、亮度 高、厚度薄、可全彩化、結構簡單以及操作環境溫度範圍 大等優勢，故已逐漸在中、小尺寸攜帶式顯示器領域中受 到矚目。 請參考第1圖，第1圖為一習知有機發光二極體10結 構的示意圖。如第1圖所示，習知有機發光二極體10結構 主要包含有一透明基板12、一設置於透明基板12上之透 明導電層（transparent conductive layer) 14，用來當做習知有 機發光二極體結構10之陽極(anode)、一設置於透明導電層 14上之有機薄膜（organic thin film)16，以及一設置於有機 薄膜16表面之金屬層（metal layer)18，用來當做習知有機 發光二極體結構10之陰極(cathode)。其中，有機薄膜16 另包含有一電洞傳輸層（hole transport layer, HTL)20、一發 6 200911019 光層（emitting layer, EL)22，以及一電子傳輸層（electron transport layer, ETL)24由下而上依序設於透明導電層14之 上。 當施加一直流(DC)電壓於習知有機發光二極體結構10 時，電子會由金屬層18(陰極）經電子傳輸層24 ’而電洞則 會由透明導電層14(陽極）經電洞傳輸層20分別注入發光層 22中，並在發光層22中經再結合成為激子（exciton)，而當 激子藉由釋放能量回到基態時，其中一定比例的能量便會 以光的型式放出，並透過透明基板12向下發光，此為習知 有機發光二極體結構10之電激發光(electroluminescent)的 原理。 然而，因為朝向透明基板發射的光線沒有全部都穿 透，會有部分的光線在透明基板與外界之間的表面被反射 而損失。因此，如2004年國際資訊顯示學會的年會技術論文摘 要(SID International Symposium Digest of Technical Papers，ρρ. 158-161)所揭露，目前已有採取在出光面表面上利用光阻形 成微透鏡（micro lens)結構規則排列，再利用折射係數互 相匹配的方式，將發光層發出來的光有效的導引出來之有 機發光二極體的架構。但是習知有機發光二極體之發光層 所發出來的光線為無方向性的，而實際從出光面射出的光 線已比有機層本身發出來的光線還少，只有直接射向正面 200911019 之 用 光=:光:：:許多發散之光線沒有做有效的利 先的利用致率，已成為業界極力努力之目標。 【發明内容】 二極Si:之二供-具有凹面鏡結構之有機發光 白知有機發光二極體之光利用率。 體結^申圍，制露—種錢發光二極 表面具有至小 續結構包含有—基板，且該基板之—上 設該第構、-設置於該基板上之第-電極、-二電極。 有機薄膜以及—設置於該有機薄膜上之第 根據本發明之申請專 極體結構，該有機發光二 二路種有機發光二 上表面具有至少L ^齡3有—基板’且該基板之-基板上表面之該二ΓΓ構…設置於該基板上之第一電極， 設 置於該第-電極上之2構與該第—電極之間有―平垣層、一 電極。 t有機薄膜以及-設置於該有機薄膜上之第 本發明藉由凹& 向觀察者之路徑行:鏡:繼^向基板之光線，以朝 订進，提升光利用率。 200911019 【實施方式】 請參考第2圖，第2圖為本發明第一實施例之有機發 光二極體之結構剖面圖。如第2圖所示，本發明之有機發 光一極體（organic light emitting diode, OLED)結構 1〇〇 包 含有一基板110、一設置於基板u〇上之第一電極12〇、一 設置於第-電極12()上之有機薄膜13G以及—設置於有機 薄膜130上之第二電極14〇，其中基板於面對第一電 極 之表面具有至少一凹面鏡結構(concave reflector)結 構而本貫施例中之第一電極120係為透明導電材料所構 成，用來作為陽極，如包含有氧化銦錫或氧化銦鋅等具有 问功函數之導電材料所構成，而第二電極14〇用來當作陰 極，由低功函數之導電材料所構成，例如硒化鋅（2：沾幻或 六硼化鑭(LaBJ等，並且基板11〇則由具有高反射性材料 所構成’例如：金屬等’使得基板11〇的表面具有反射效 果。 有機薄膜130另包含有一電洞傳輸層（h〇ie transport layer, HTL)150設置於該第一電極i2〇之上、一發光層 (emitting layer，EL) 160設置於該電洞傳輸層15〇之上，以 及一電子傳輸層（electron transport layer, ETL) 170 設置於該 發光層之上。其中’有機薄膜130可利用加熱蒸鍍(thermal evaporation)法或旋轉塗佈（spin_coating)法製作於第一電極 200911019 在本實施例中，當施加一電壓於有機發光二極體結構 100時，電洞會由第一電極120(陽極）經電洞傳輸層150， 而電子則會由第二電極140(陰極）經電子傳輸層170分別注 入發光層160中，經再結合成為激子（exciton)，而當激子 藉由釋放能量回到基態時，有一定比例的能量會以光的型 式放出，且其方向是任意的，因此，從有機薄膜130所發 出來的光四處發散後，除了往第二電極140發散的光直接 射出以外，其他發散的光大部份會射向第一電極120。由 於第一電極120為透明材料所構成，因此射向第一電極120 之光線會穿透第一電極120而射向基板110。因為本發明 於基板110之上表面具有凹面鏡結構設計，射向基板110之 光線可被反射並且改變光的行進路徑，使光線向基板110 中心點聚集，提升出光量，因此光的有效利用率便得以增 加。此外，由於該凹面鏡結構直接製作於基板上，第一電 極120再設置於基板上，可改善凹面鏡結構製作於第一電 極表面時，所造成電極表面不平整之問題。 具有凹面鏡結構之基板與第一電極之間，亦可配置一 層平坦層，該平坦層可以塗佈Si02形成。平坦層使具有凹 面鏡結構之基板表面平坦，第一電極再配置於平坦層上 層，可避免因第一電極層過薄，使得第一電極與基板表面 共形，導致第一電極表面不均之問題。 10 200911019 另外，值得-提的是，於本實施例中，第一電極12〇 亦可用來當作陰極，則由低功函數之導電㈣所構成，例 如硒化鋅（ZnSe)或六硼化鑭(LaB6)等，而第二電極丨4〇則用 來當作陽極’ Μ功函數之透明導電材料所構成，例如氧 化銦錫或氧化銦鋅等。 請參考第3圖’第3圖為本發明第二實施例之有機發 光二極體之結構剖面圖。如第3圖所示，相較於第一實施 例，本實施例之有機發光二極體結構1〇〇另包含有一反射 層180設置於基板11〇與第一電極12〇之間，而基板η〇 具有凹面鏡結構而使得形成於基板110表面之反射層180 亦具有相對應之凹面鏡，並且反射層18〇為高反射性材料 冓成如金屬等，基板可為玻璃基板或塑性基板，而第 ^。120與第二電極丨4〇則為導電材料所構成，例如石西 (ZnSe)、六硼化鑭(LaB6)(作為陰極）、氧化銦錫或氧化 有(反乍為陽極）等’因此可藉由反射層18G之凹面鏡結構 〃光。射特性，將向下發散之光線反射且聚集而向上發 該平=射層I80與第一電極120之間亦可配置一平坦層， 上層_以塗佈Si〇2形成，第一電極12〇再配置於平坦層 °月參考第4圖，第4圖為本發明第三實施例之有機發 200911019 光二極體之結構剖面圖。如第4圖所示，本實施例之有機 • 發光二極體結構100另包含一反射層180設置於基板11〇 之下表面190 ’並且基板110下表面190具有至少一凹面 鏡結構，並且基板110之上表面195係為平坦的，而第一電極 120與第二電極140皆為透明導電材料所構成，基板u〇 則為透明材料所構成，反射層180則為高反射性材料所構 成，例如：金屬等。在本實施例中，反射層18〇藉由形成 於基板110上，而具有相對應的凹面鏡結構，使光線得以 被反射層反射與聚集，以提升光利用率。 综合上述說明，本發明之有機發光二極體結構的基板 面對電極或反射層之表面具有至少一凹面鏡結構，^1 施例為具高反射性之基板具有凹面鏡結構，以使從有機= 膜發出來的光穿透電極後，射向高反射性之基板而不至於 損失，並藉由凹面鏡結構反射聚集射向基板之光線，以朝 向觀察者之路徑行進，進而提升光利用率。 此外，本發明之有機發光二極體結構並不偈限於尸呈 有單-形狀及數量、規則或不規則排列之凹面鏡，請= 第5至7圖。第5圖則為本發明之有機發光二極體結 時具有複數個圓形凹面鏡之上視圖’於第5圖中，由於 圓形凹面鏡結構之間仍存在許多無聚光之平整區域，因^ 另可具有數個較小的圓形凹面鏡或多邊形凹面鏡填充於= 12 200911019 圓形結構之間隙，而第6圖則為本發明之有機發光二極體 結構同時具有複數個具規則排列之矩形凹面鏡之上视圖， 第7圖為本發明之有機發光二極體結構同時具有複數個具 規則排列之矩形、菱形與三角形凹面鏡之上視圖，因此本 發明之有機發光二極體之凹面鏡不只可單一圓形、方形或 其他幾何形狀’還可為複數個幾何形狀之組合，並且複數 個規則或不規則排列之具有凹面鏡的有機發光二極體亦應 屬本發明之涵蓋範圍。另外，本發明之第一實施例之製作 方式可藉由提供一基板，然後利用光微影製程或機械加工 4方式於基板表面上形成至少一凹面鏡結構，接著，形成 第一電極於基板上’再將有機發光材料用蒸鍍或旋轉塗佈 的方式形成於第一電極上，最後將第二電極形成於有機薄 膜上，即完成一有機發光二極體。 察者行進 相較於習知技術，由於本發明之有機發光二極體結構 之基板具有凹面鏡，使得從有機薄膜發出來的光射 後不至於射向基板之先線_ 範 _之均等變化與修二申請專利 【圖式簡單說明】 13 200911019 第1圖為-習知有機發光二極體結構的示音、圖。 第圖2圖為本發明第-實施例之有機發光二極體之結構剖面 第^ 圖為本發明第二實施例之有機發光二極體之結構剖面 第4圖為本發明第三實施例之有機發光二極體之結構剖面 圖。 第5圖則為本發明之有機發光二極體結構㈣具有複數個 圓形凹面鏡之上視圖。 第6圖則為本發明之有機發光二極體結構同時具有複數個 具規則排列之矩形凹面鏡之上視圖。 第7圖為本發明之有機發光二極體結構同時具有複數個具 規則排列之矩形、菱形與三角形凹面鏡之上視圖。 【主要元件符號說明】 100有機發光二極體結構110基板 120第一電極 140第二電極 160發光層 180反射層 195上表面 130有機薄膜 150電洞傳導層 170電子傳導層 190下表面 14200911019 IX. Description of the invention: * [Technical field to which the invention pertains] ‘ The present invention provides an organic light-emitting diode structure, in particular, an organic light-emitting diode having a concave mirror structure to improve light utilization efficiency. [Prior Art] In the flat panel display, the 'organic light-emitting diode (OLED) display started late, but it has self-luminous, wide viewing angle, fast response, low power consumption, and strong contrast. With high brightness, thin thickness, full color, simple structure and large operating temperature range, it has gradually attracted attention in the field of medium and small size portable displays. Please refer to Fig. 1. Fig. 1 is a schematic view showing the structure of a conventional organic light-emitting diode 10. As shown in FIG. 1 , the conventional organic light emitting diode 10 structure mainly includes a transparent substrate 12 and a transparent conductive layer 14 disposed on the transparent substrate 12 for use as a conventional organic light emitting diode. An anode of the bulk structure 10, an organic thin film 16 disposed on the transparent conductive layer 14, and a metal layer 18 disposed on the surface of the organic thin film 16 are used as a conventional organic The cathode of the light emitting diode structure 10. The organic film 16 further includes a hole transport layer (HTL) 20, a hairline 6 200911019, an emission layer (EL) 22, and an electron transport layer (ETL) 24 The upper layer is sequentially disposed on the transparent conductive layer 14. When a direct current (DC) voltage is applied to the conventional organic light emitting diode structure 10, electrons will pass from the metal layer 18 (cathode) through the electron transport layer 24' and the holes will pass through the transparent conductive layer 14 (anode). The hole transport layer 20 is injected into the light-emitting layer 22, respectively, and recombined into an exciton in the light-emitting layer 22, and when the excitons return to the ground state by releasing energy, a certain proportion of the energy is light. The pattern is discharged and illuminates downward through the transparent substrate 12, which is the principle of electroluminescent of the conventional organic light emitting diode structure 10. However, since not all of the light emitted toward the transparent substrate is penetrated, part of the light is reflected and lost on the surface between the transparent substrate and the outside. Therefore, as disclosed in the SID International Symposium Digest of Technical Papers (ρρ. 158-161), it has been proposed to use a photoresist to form a microlens on the surface of the illuminating surface. The lens structure is regularly arranged, and the structure of the organic light-emitting diode which effectively guides the light emitted from the light-emitting layer is guided by the mutual matching of the refractive coefficients. However, it is known that the light emitted from the light-emitting layer of the organic light-emitting diode is non-directional, and the light actually emitted from the light-emitting surface is less than the light emitted from the organic layer itself, and is only directly directed to the front surface of 200911019. Light =: Light::: Many divergent rays have not been used effectively to make use of the rate, which has become the goal of the industry's efforts. SUMMARY OF THE INVENTION Two-pole Si: two for - organic light-emitting with a concave mirror structure The light utilization efficiency of the white organic light-emitting diode. The body is formed by the surface of the light-emitting diode, and the surface of the light-emitting diode has a substrate, and the substrate is provided with the first electrode, the first electrode and the second electrode disposed on the substrate. . An organic thin film and a coated special body structure according to the present invention, wherein the organic light-emitting two-way organic light-emitting two upper surface has at least L ^ 3 3 - substrate ' and the substrate-substrate The second electrode of the upper surface is disposed on the first electrode of the substrate, and the second electrode disposed on the first electrode and the first electrode have a flat layer and an electrode. The organic film and the first invention disposed on the organic film are arranged by the concave & toward the observer: the mirror: the light toward the substrate to be customized to enhance the light utilization efficiency. [Embodiment] Please refer to Fig. 2, which is a cross-sectional view showing the structure of an organic light-emitting diode according to a first embodiment of the present invention. As shown in FIG. 2, the organic light emitting diode (OLED) structure 1A of the present invention comprises a substrate 110, a first electrode 12 disposed on the substrate u, and a first electrode. An organic film 13G on the electrode 12() and a second electrode 14A disposed on the organic film 130, wherein the substrate has at least one concave reflector structure on the surface facing the first electrode, and the present embodiment The first electrode 120 is made of a transparent conductive material and is used as an anode, such as a conductive material having a work function including indium tin oxide or indium zinc oxide, and the second electrode 14 is used as a conductive material. The cathode is composed of a conductive material having a low work function, such as zinc selenide (2: smear or lanthanum hexaboride (LaBJ, etc., and the substrate 11 〇 is composed of a highly reflective material such as: metal, etc.) The surface of the substrate 11 has a reflective effect. The organic film 130 further includes a hole transport layer (HTL) 150 disposed on the first electrode i2, and an emission layer (EL) 160. Setting The hole transport layer 15 is disposed above the electron transport layer (ETL) 170. The organic film 130 can be thermally evaporated or spin coated. (Spin_coating) method is fabricated on the first electrode 200911019. In this embodiment, when a voltage is applied to the organic light emitting diode structure 100, the hole is transmitted from the first electrode 120 (anode) through the hole transport layer 150, and the electron Then, the second electrode 140 (cathode) is injected into the light-emitting layer 160 through the electron transport layer 170, and is recombined into an exciton, and when the excitons return to the ground state by releasing energy, there is a certain proportion of energy. It will be emitted in the form of light, and its direction is arbitrary. Therefore, after the light emitted from the organic film 130 is diverged, most of the divergent light will be emitted except for the light that is diverged toward the second electrode 140. To the first electrode 120. Since the first electrode 120 is made of a transparent material, the light that is directed to the first electrode 120 passes through the first electrode 120 and is directed toward the substrate 110. Because the present invention is on the substrate 110 The upper surface has a concave mirror structure design, and the light directed to the substrate 110 can be reflected and change the traveling path of the light, so that the light is concentrated toward the center point of the substrate 110, thereby increasing the amount of light, so that the effective utilization of light is increased. The concave mirror structure is directly formed on the substrate, and the first electrode 120 is further disposed on the substrate, which can improve the problem that the surface of the electrode is uneven when the concave mirror structure is fabricated on the surface of the first electrode. Between the substrate having the concave mirror structure and the first electrode, a flat layer may be disposed, and the flat layer may be formed by coating SiO 2 . The flat layer flattens the surface of the substrate having the concave mirror structure, and the first electrode is disposed on the upper layer of the flat layer to avoid the problem that the first electrode is conformal to the surface of the substrate due to the first electrode layer being too thin, resulting in uneven surface of the first electrode. . 10 200911019 In addition, it is worth mentioning that in the present embodiment, the first electrode 12 〇 can also be used as a cathode, and is composed of a low work function conductive (IV), such as zinc selenide (ZnSe) or hexaboride.镧 (LaB6), etc., and the second electrode 丨4〇 is used as a transparent conductive material of the anode's work function, such as indium tin oxide or indium zinc oxide. Referring to Fig. 3, Fig. 3 is a cross-sectional view showing the structure of an organic light-emitting diode according to a second embodiment of the present invention. As shown in FIG. 3, the organic light emitting diode structure 1 of the present embodiment further includes a reflective layer 180 disposed between the substrate 11A and the first electrode 12? The η 〇 has a concave mirror structure such that the reflective layer 180 formed on the surface of the substrate 110 also has a corresponding concave mirror, and the reflective layer 18 〇 is a highly reflective material such as a metal, and the substrate can be a glass substrate or a plastic substrate, and the ^. 120 and the second electrode 丨4〇 are made of a conductive material, such as zexi (ZnSe), lanthanum hexaboride (LaB6) (as a cathode), indium tin oxide or oxidized (reverse anodic anode), etc. The light is reflected by the concave mirror structure of the reflective layer 18G. And a flat layer is disposed between the flattening layer I80 and the first electrode 120, and the upper layer is formed by coating Si〇2, and the first electrode 12〇 is formed by reflecting and collecting the downward diverging light. Further, it is disposed on the flat layer. Referring to FIG. 4, FIG. 4 is a cross-sectional view showing the structure of the organic light-emitting diode 200911019 according to the third embodiment of the present invention. As shown in FIG. 4, the organic light-emitting diode structure 100 of the present embodiment further includes a reflective layer 180 disposed on the lower surface 190' of the substrate 11 and a lower surface 190 of the substrate 110 having at least one concave mirror structure, and the substrate 110 The upper surface 195 is flat, and the first electrode 120 and the second electrode 140 are both made of a transparent conductive material, the substrate u is made of a transparent material, and the reflective layer 180 is made of a highly reflective material, for example, : Metal, etc. In the present embodiment, the reflective layer 18 is formed on the substrate 110 to have a corresponding concave mirror structure to allow light to be reflected and concentrated by the reflective layer to enhance light utilization. In summary, the substrate of the organic light emitting diode structure of the present invention has at least one concave mirror structure facing the surface of the electrode or the reflective layer, and the substrate having the high reflectivity has a concave mirror structure to make the organic film After the emitted light penetrates the electrode, it is directed to the highly reflective substrate without loss, and the light that is directed toward the substrate is reflected and reflected by the concave mirror structure to travel toward the observer, thereby improving the light utilization efficiency. Further, the organic light-emitting diode structure of the present invention is not limited to a concave mirror having a single-shape and number, regular or irregular arrangement of the corpses, please = Figures 5 to 7. Figure 5 is a top view of a plurality of circular concave mirrors in the organic light-emitting diode junction of the present invention. In Figure 5, since there are still many flat areas without concentrating between the circular concave mirror structures, Alternatively, a plurality of smaller circular concave mirrors or polygonal concave mirrors may be filled in the gap of the circular structure of = 12 200911019, and the sixth embodiment is the organic light emitting diode structure of the present invention having a plurality of rectangular concave mirrors arranged regularly. The top view, FIG. 7 is a top view of the organic light emitting diode structure of the present invention having a plurality of rectangular, diamond and triangular concave mirrors arranged in a regular manner, so that the concave mirror of the organic light emitting diode of the present invention is not only single A circular, square or other geometric shape 'may also be a combination of a plurality of geometric shapes, and a plurality of regularly or irregularly arranged organic light-emitting diodes having a concave mirror are also within the scope of the present invention. In addition, the first embodiment of the present invention can be formed by providing a substrate, and then forming at least one concave mirror structure on the surface of the substrate by photolithography or machining 4, and then forming a first electrode on the substrate. Then, the organic light-emitting material is formed on the first electrode by vapor deposition or spin coating, and finally the second electrode is formed on the organic film, that is, an organic light-emitting diode is completed. Compared with the prior art, the substrate of the organic light-emitting diode structure of the present invention has a concave mirror, so that the light emitted from the organic film does not hit the first line of the substrate. The second application patent [simplified description of the drawings] 13 200911019 The first picture shows the sound and diagram of the structure of the organic light-emitting diode. 2 is a cross-sectional view showing a structure of an organic light-emitting diode according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view showing a structure of an organic light-emitting diode according to a second embodiment of the present invention. FIG. 4 is a third embodiment of the present invention. A cross-sectional view of the structure of an organic light-emitting diode. Fig. 5 is a top view of the organic light-emitting diode structure (4) of the present invention having a plurality of circular concave mirrors. Fig. 6 is a top view of the organic light-emitting diode structure of the present invention having a plurality of rectangular concave mirrors arranged in a regular manner. Figure 7 is a top view of the organic light-emitting diode structure of the present invention having a plurality of rectangular, diamond-shaped and triangular concave mirrors arranged at regular intervals. [Main component symbol description] 100 organic light emitting diode structure 110 substrate 120 first electrode 140 second electrode 160 light emitting layer 180 reflective layer 195 upper surface 130 organic film 150 hole conducting layer 170 electron conducting layer 190 lower surface 14