华体会官方网页版-华体会(中国):Deep-ultraviolet LEDs with an Al-graded p-AlGaN layer exhibiting high wall-plug efficiency and high modulation bandwidth simultaneously
Cui, Bingyue; Yang, Jie; Gao, Xingfa; He, Jiaheng; Liu, Zhe; Cheng, Zhe; Zhang, Yun Source: Semiconductor Science and Technology, v 39, n 3, March 2024;
Abstract:
This work demonstrated a deep-ultraviolet (DUV) LED with an Al-graded p-AlGaN contact layer above the electron blocking layer to alleviate p-type contact resistance, the asymmetry of carriers transport, and the polarization effect. The fitting results from the ABC + f(n) model revealed that the LED has a higher radiative recombination coefficient than the conventional structures ever reported, which contributes to a lower carrier lifetime. The light output power of the LED at 350 mA is 44.71 mW, the peak external quantum efficiency (EQE) at 22.5 mA is 5.12%, the wall-plug efficiency at 9 mA is 4.40%. The 3 dB electrical-to-optical modulation bandwidth of the graded p-AlGaN contact layer LED is 390 MHz after impedance matching. In short, this study provides an in-depth analysis of the physical mechanism of the enhanced EQE and decreased carrier lifetime of DUV LEDs with Al-graded AlGaN as a p-type contact layer.
? 2024 Institute of Semiconductors, Chinese Academy of Sciences. Published by IOP Publishing Ltd. (53 refs.)
