Effects of V/III ratio on the growth of a-plane GaN films  

作　　者：谢自力 李弋 刘斌 张荣 修向前 陈鹏 郑有炓 

机构地区：[1]Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronics Science and Engineering, Nanjing University

出　　处：《Chinese Physics B》2011年第10期368-372,共5页中国物理B（英文版）

基　　金：supported by the Special Funds for Major State Basic Research Project of China (Grant No. 2011CB301900);High Technology Research Program of China (Grant No. 2009AA03A198);the National Natural Science Foundation of China (Grant Nos. 60990311, 60721063, 60906025, 60936004, 60731160628, and 60820106003);the Natural Science Foundation of Jiangsu Province of China (Grant Nos. BK2008019, BK2010385, BK2009255, and BK2010178);the Research Funds from NJU-Yangzhou Institute of Opto-electronics, China

摘　　要：The non-polar a-plane GaN is grown on an r-plane sapphire substrate directly without a buffer layer by metal- organic chemical vapour deposition and the effects of V/III ratio growth conditions are investigated. Atomic force microscopy results show that triangular pits are formed at a relatively high V/III ratio, while a relatively low V/III ratio can enhance the lateral growth rate along the c-axis direction. The higher V/III ratio leads to a high density of pits in comparison with the lower V/III ratio. The surface morphology is improved greatly by using a low V/III ratio of 500 and the roughness mean square of the surface is only 3.9 nm. The high resolution X-ray diffraction characterized crystal structural results show that the rocking curve full width at half maximum along the m axis decreases from 0.757° to 0.720°, while along the c axis increases from 0.220° to 0.251° with the V/III increasing from 500 μmol/min to 2000 μmol/min, which indicates that a relatively low V/III ratio is conducible to the c-axis growth of a-plane GaN.The non-polar a-plane GaN is grown on an r-plane sapphire substrate directly without a buffer layer by metal- organic chemical vapour deposition and the effects of V/III ratio growth conditions are investigated. Atomic force microscopy results show that triangular pits are formed at a relatively high V/III ratio, while a relatively low V/III ratio can enhance the lateral growth rate along the c-axis direction. The higher V/III ratio leads to a high density of pits in comparison with the lower V/III ratio. The surface morphology is improved greatly by using a low V/III ratio of 500 and the roughness mean square of the surface is only 3.9 nm. The high resolution X-ray diffraction characterized crystal structural results show that the rocking curve full width at half maximum along the m axis decreases from 0.757° to 0.720°, while along the c axis increases from 0.220° to 0.251° with the V/III increasing from 500 μmol/min to 2000 μmol/min, which indicates that a relatively low V/III ratio is conducible to the c-axis growth of a-plane GaN.

关 键 词：V/III ratio a-plane GaN NON-POLAR metal-organic chemical vapour deposition 

分 类 号：O484.1[理学—固体物理]