具有啁啾超晶格电子减速层的AlGaN基深紫外发光二极管的性能增强

Enhanced Performance of AlGaN-Based Deep Ultraviolet Light-Emitting Diodes with Chirped Superlattice Electron Deceleration Layer.

作者信息

Hu Jiahui, Zhang Jun, Zhang Yi, Zhang Huixue, Long Hanling, Chen Qian, Shan Maocheng, Du Shida, Dai Jiangnan, Chen Changqing

机构信息

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.

出版信息

Nanoscale Res Lett. 2019 Nov 21;14(1):347. doi: 10.1186/s11671-019-3201-x.

DOI:10.1186/s11671-019-3201-x

PMID:31754922

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6872697/

Abstract

AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) suffer from electron overflow and insufficient hole injection. In this paper, novel DUV LED structures with superlattice electron deceleration layer (SEDL) is proposed to decelerate the electrons injected to the active region and improve radiative recombination. The effects of several chirped SEDLs on the performance of DUV LEDs have been studied experimentally and numerically. The DUV LEDs have been grown by metal-organic chemical vapor deposition (MOCVD) and fabricated into 762 × 762 μm chips, exhibiting single peak emission at 275 nm. The external quantum efficiency of 3.43% and operating voltage of 6.4 V are measured at a forward current of 40 mA, indicating that the wall-plug efficiency is 2.41% of the DUV LEDs with ascending Al-content chirped SEDL. The mechanism responsible for this improvement is investigated by theoretical simulations. The lifetime of the DUV LED with ascending Al-content chirped SEDL is measured to be over 10,000 h at L50, due to the carrier injection promotion.

摘要

基于AlGaN的深紫外（DUV）发光二极管（LED）存在电子溢出和空穴注入不足的问题。本文提出了具有超晶格电子减速层（SEDL）的新型DUV LED结构，以减缓注入有源区的电子速度并提高辐射复合效率。通过实验和数值模拟研究了几种啁啾SEDL对DUV LED性能的影响。DUV LED通过金属有机化学气相沉积（MOCVD）生长，并制成762×762μm的芯片，在275nm处呈现单峰发射。在40mA的正向电流下，测得外部量子效率为3.43%，工作电压为6.4V，这表明具有Al含量递增啁啾SEDL的DUV LED的壁插效率为2.41%。通过理论模拟研究了这种改善的机制。由于载流子注入促进作用，具有Al含量递增啁啾SEDL的DUV LED在L50时的寿命测量超过10000小时。