Lei Po-Hsun, Yang Chyi-Da, Huang Po-Chun, Yeh Sheng-Jhan
Institute of Electro-Optical and Material Science, National Formosa University, No. 64, Wunhua Rd., Huwei, Yunlin County 632, Taiwan.
Department of Microelectronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 811, Taiwan.
Micromachines (Basel). 2019 Apr 10;10(4):239. doi: 10.3390/mi10040239.
In this study, we propose a liquid-phase-deposited silver nanoparticle embedded ZnO (LPD-Ag NP/ZnO) thin film at room temperature to improve the light extraction efficiency (LEE) for InGaN/GaN light-emitting diodes (LEDs). The treatment solution for the deposition of the LPD-Ag/NP ZnO thin film comprised a ZnO-powder-saturated HCl and a silver nitrate (AgNO₃) aqueous solution. The enhanced LEE of an InGaN/GaN LED with the LPD-Ag NP/ZnO window layer can be attributed to the surface texture and localized surface plasmon (LSP) coupling effect. The surface texture of the LPD-Ag/NP ZnO window layer relies on the AgNO₃ concentration, which decides the root-mean-square (RMS) roughness of the thin film. The LSP resonance or extinction wavelength also depends on the concentration of AgNO₃, which determines the Ag NP size and content of Ag atoms in the LPD-Ag NP/ZnO thin film. The AgNO₃ concentration for the optimal LEE of an InGaN/GaN LED with an LPD-Ag NP/ZnO window layer occurs at 0.05 M, which demonstrates an increased light output intensity that is approximately 1.52 times that of a conventional InGaN/GaN LED under a 20-mA driving current.
在本研究中，我们提出在室温下通过液相沉积法制备嵌入银纳米颗粒的氧化锌（LPD-Ag NP/ZnO）薄膜，以提高氮化铟镓/氮化镓发光二极管（LED）的光提取效率（LEE）。用于沉积LPD-Ag/NP ZnO薄膜的处理溶液由氧化锌粉末饱和的盐酸和硝酸银（AgNO₃）水溶液组成。具有LPD-Ag NP/ZnO窗口层的氮化铟镓/氮化镓LED的LEE增强可归因于表面纹理和局域表面等离子体（LSP）耦合效应。LPD-Ag/NP ZnO窗口层的表面纹理取决于AgNO₃浓度，该浓度决定了薄膜的均方根（RMS）粗糙度。LSP共振或消光波长也取决于AgNO₃的浓度，这决定了LPD-Ag NP/ZnO薄膜中Ag纳米颗粒尺寸和Ag原子含量。具有LPD-Ag NP/ZnO窗口层的氮化铟镓/氮化镓LED实现最佳LEE时的AgNO₃浓度为0.05 M，这表明在20 mA驱动电流下，光输出强度增加，约为传统氮化铟镓/氮化镓LED的1.52倍。
