The effects of sapphire nitridation on GaN growth by metalorganic chemical vapour deposition  

作　　者：乐伶聪 赵德刚 吴亮亮 邓懿 江德生 朱建军 刘宗顺 王辉 张书明 张宝顺 杨辉 

机构地区：[1]State Key Laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences [2]Suzhou Institute of Nano-tech and Nano-bionics,Chinese Academy of Sciences

出　　处：《Chinese Physics B》2011年第12期400-403,共4页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation for Distinguished Young Scholars of China (Grant No. 60925017);the National Natural Science Foundation of China (Grant Nos. 10990100,60836003,and 60776047);the National Basic Research Program of China (Grant No. 2007CB936700);the National High Technology Research and Development Program of China(Grant No. 2007AA03Z401)

摘　　要：In situ optical reflectivity measurements are employed to monitor the GaN epilayer growth process above a lowtemperature GaN buffer layer on a c-plane sapphire substrate by metalorganic chemical vapour deposition. It is found that the lateral growth of the GaN islands and their coalescence are promoted in the initial growth stage if optimized nitridation time and temperature are selected when the substrate is pre-exposed to ammonia. As confirmed by atomic force microscopy observations, the quality of the CaN epilayers is closely dependent on the surface morphology of the nitridated buffer layer, especially grain size and nucleation density.In situ optical reflectivity measurements are employed to monitor the GaN epilayer growth process above a lowtemperature GaN buffer layer on a c-plane sapphire substrate by metalorganic chemical vapour deposition. It is found that the lateral growth of the GaN islands and their coalescence are promoted in the initial growth stage if optimized nitridation time and temperature are selected when the substrate is pre-exposed to ammonia. As confirmed by atomic force microscopy observations, the quality of the CaN epilayers is closely dependent on the surface morphology of the nitridated buffer layer, especially grain size and nucleation density.

关 键 词：X-ray diffraction metalorganic chemical vapour deposition nitrides 

分 类 号：TN304.2[电子电信—物理电子学]