Analysis of TM/TE mode enhancement and droop reduction by a nanoporous n-AIGaN underlayer in a 290 nm UV-LED  

作　　者：YUFENG LI CHENYU WANG YE ZHANG PENG HU SHENGNAN ZHANG MENGQI DU XILIN SU QIANG LI FENG YUN 

机构地区：[1]Shaanxi Provincial Key Laboratory of Photonics&Information Technology,Xi'an Jiaotong University,Xi'an 710049,China [2]Solid-State Lighting Engineering Research Center,Xi'an Jiaotong University,Xi'an 710049,China

出　　处：《Photonics Research》2020年第6期806-811,共6页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(61574114,61774121);National Key Research and Development Program of China(2016YFB0400801);Fundamental Research Funds for the Central Universities(Z201805198).

摘　　要：A full structure 290 nm ultraviolet light emitting diode(UV-LED)with a nanoporous n-AlGaN underlayer was fabricated by top via hole formation followed by high-voltage electrochemical etching.The 20 to 120 nm nanopores were prepared in regular doped n-AlGaN by adjusting the etching voltage.The comparison between the Raman spectrum and the photoluminescence wavelength shows that the biaxial stress in the nanoporous material is obviously relaxed.The photoluminescence enhancement was found to be highly dependent on the size of the pores.It not only improves the extraction efficiency of top-emitting transverse-electric(TE)-mode photons but also greatly improves the efficiency of side emitting tran sverse-magnetic(TM)-mode photons.This leads to the polarization change of the side-emitting light from-0.08 to-0.242.The intensity of the electroluminescence was increased by 36.5%at 100 mA,and the efficiency droop at high current was found to decrease from 61%to 31%.

关 键 词：pores ULTRAVIOLET relaxed 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TN312.8[电子电信—物理电子学]