Horng Ray-Hua, Chuang Shih-Hao, Tien Ching-Ho, Lin Sin-Cyuan, Wuu Dong-Sing
Opt Express. 2014 May 5;22 Suppl 3:A941-6. doi: 10.1364/OE.22.00A941.
A high-performance flip-chip light-emitting diode (FCLED) with a Ni/Ag metallic film as high reflectivity mirror (92.67%) of p-type electrode was successfully fabricated. The effect of geometric electrode patterns on the blue InGaN/GaN LEDs was investigated and analyzed qualitatively its current spreading in the active region. With different electrode patterns, these devices were experimented and simulated by simple electrical circuits in order to confirm its current-voltage characteristics and light emission pattern. It was found that the forward voltages of these FCLEDs were about 3.6 V (@350 mA). The light output power of FCLEDs with circle-round type electrode was 368 mW at an injection current of 700 mA. From these optoelectronic measurement and thermal infrared images, we proposed some design methodologies for improved current spreading, light output power, droop efficiency and thermal performance.
成功制备了一种高性能倒装芯片发光二极管（FCLED），其p型电极采用Ni/Ag金属膜作为高反射率镜面（反射率为92.67%）。研究并定性分析了几何电极图案对蓝色InGaN/GaN发光二极管有源区电流扩展的影响。采用不同的电极图案，通过简单电路对这些器件进行了实验和模拟，以确定其电流-电压特性和发光图案。结果发现，这些FCLED的正向电压约为3.6 V（@350 mA）。圆形电极的FCLED在700 mA注入电流下的光输出功率为368 mW。通过这些光电测量和热红外图像，我们提出了一些改进电流扩展、光输出功率、效率下降和热性能的设计方法。
