講演情報
[16p-PA3-3]Enhancement of light extraction efficiency in AlGaN-based deep-ultraviolet light-emitting diodes by nanostructure reflection
〇Guodong Hao1, Manabu Taniguchi1, Shin-ichiro Inoue1 (1.NICT)
キーワード：
AlGaN DUV-LED、light extraction efficiency、wall-plug efficiency
AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) have shown great potential for a wide range of applications, including disinfection and sterilization, photolithography, ultraviolet curing, and solar-blind communications. We have previously made significant developments in 275-nm DUV-LEDs by employing a mesh-like micro p-electrode combined with HfO2 scattering nanostructures, resulting in a high wall-plug efficiency (WPE) of 9.1%.Further improvement in WPE toward the theoretical limit is still required for DUV-LEDs. The relatively low light extraction efficiency (LEE) remains a major factor limiting the WPE of AlGaN-based DUV-LEDs, primarily due to total internal reflection at light extraction surface and strong light absorption in the p-GaN ohmic contact layer. In this talk, to enhance the LEE in flip-chip DUV-LEDs, we employ the mesh-like metal/p-GaN p-electrode to suppress light absorption in the p-GaN layer. We then focus on enhancing light reflection in p-side by modifying both the geometry of the nanostructures and the materials with different refractive indices.