LIGHT-EMITTING ELEMENT

• Main Authors: MURAMOTO EIJI, YAMAGAMI YUYA, KISHI AKINORI, OTSUKA TAKUMI, NISHIKAGE HARUHIKO, KAMIMOTO SHOTA
• Format: Patent
• Language: English; Japanese
• Published: 10.08.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

To provide a light-emitting element with high luminous efficiency.SOLUTION: A light-emitting element includes a semiconductor structure including an n-side layer, a p-side layer, and an active layer disposed between the n-side layer and the p-side layer and emitting ultraviolet ray, an n-electrode electrically connected to the n-side layer, and a p-electrode including a first metal layer in contact with the p-side layer an electrically connected to the p-side layer. The p-side layer includes a first layer, a second layer disposed on the first layer, and a third layer disposed on the second layer, each containing p-type impurities. A surface of the second layer includes an exposed region exposed from the third layer. The first layer and the second layer contain Al. The third layer is a layer with an Al composition ratio smaller than the Al composition ratio of the second layer, or a layer without Al. The thickness of each of the second layer and the third layer is smaller than the thickness of the first layer. The p-type impurity concentration of the third layer is higher than the p-type impurity concentration of the second layer. The first metal layer is disposed in contact with the exposed region of the second layer and a surface of the third layer.SELECTED DRAWING: Figure 3 【課題】発光効率が高い発光素子を提供する。【解決手段】それぞれが窒化物半導体からなる、ｎ側層と、ｐ側層と、ｎ側層とｐ側層との間に位置し紫外線を発する活性層と、を含む半導体構造体と、ｎ側層に電気的に接続されるｎ電極と、ｐ側層に接する第１金属層を有し、ｐ側層に電気的に接続されるｐ電極と、を含み、ｐ側層は、それぞれがｐ型不純物を含む、第１層と、第１層上に配置される第２層と、第２層上に配置される第３層と、を有し、第２層の表面は、第３層から露出する露出領域を有し、第１層及び第２層は、Ａｌを含み、第３層は、第２層のＡｌ組成比よりも低いＡｌ組成比である層、又は、Ａｌを含まない層であり、第２層の厚さ及び第３層の厚さのそれぞれは、第１層の厚さよりも薄く、第３層のｐ型不純物濃度は、第２層のｐ型不純物濃度よりも高く、第１金属層は、第２層の露出領域と、第３層の表面と、に接して配置される発光素子。【選択図】図３