Effects of the V/III Ratio of a Low-Temperature GaN Buffer Layer on the Structural and Optical Properties of a-GaN Films Grown on r-Plane Sapphire Substrates by MOCVD  

作　　者：TIAN Yu DAI Jiang-Nan XIONG Hui ZHENG Guang RYU My FANG Yan-Yan CHEN Chang-Qing 田玉;戴江南;熊晖;郑广;RYU My;方妍妍;陈长清(Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074;Department of Physics,Jianghan University,Wuhan 430056;Department of Physics,Kangwon National University,Kangwon-do 200-701,Republic of Korea)

机构地区：[1]Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074 [2]Department of Physics,Jianghan University,Wuhan 430056 [3]Department of Physics,Kangwon National University,Kangwon-do 200-701,Republic of Korea

出　　处：《Chinese Physics Letters》2012年第8期253-256,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 60976042;the Major Program of National Natural Science Foundation of China under Grant No 10990100;the National Basic Research Program of China under Grant Nos 2010CB923204 and 2012CB619302。

摘　　要：We investigate the effects of the V/III ratio of a low-temperature GaN buffer layer on the growth of the overlaying nonpolar-plane GaN film grown on-plane sapphire by metal-organic chemical-vapor deposition(MOCVD).With other experimental conditions keeping fixed,the low-temperature GaN buffer layers are grown under various V/III ratios of 1000,3000,6000 and 9000,respectively.The characteristics of the-plane GaN films are analyzed by scanning electron microscopy,high resolution x-ray diffraction,Raman spectrum,and low temperature photoluminescence.The results show that the V/III ratio of the buffer layer has significant effects on the crystal quality of the a-plane GaN film,and a V/III ratio of 6000 is found to be the most suitable condition to achieve pit-free flat GaN surface.

关 键 词：MOCVD SAPPHIRE film 

分 类 号：TN3[电子电信—物理电子学]