Twinning in Low-Temperature MOCVD Grown GaN on (001) GaAs Substrate  

低温MOCVD法沉积的GaN/GaAs(001)薄膜中的孪晶现象(英文)

作　　者：沈晓明[1] 王玉田[2] 王建峰[2] 刘建平[2] 张纪才[2] 郭立平[3] 贾全杰[3] 姜晓明[3] 胡正飞[1] 杨辉[2] 梁骏吾[1] 

机构地区：[1]同济大学半导体与信息技术研究所,上海200092 [2]中国科学院半导体研究所集成光电国家重点实验室,北京100083 [3]中国科学院高能物理研究所同步辐射中心,北京100037

出　　处：《Journal of Semiconductors》2005年第4期645-650,共6页半导体学报（英文版）

基　　金：国家博士后科学基金(批准号:2003034271);国家自然科学基金(批准号:69825107)资助项目~~

摘　　要：GaN buffer layers (thickness ～60nm) grown on GaAs(001) by low-temperature MOCVD are investigated by X-ray diffraction pole figure measurements using synchrotron radiation in order to understand the heteroepitaxial growth features of GaN on GaAs(001) substrates.In addition to the epitaxially aligned crystallites,their corresponding twins of the first and the second order are found in the X-ray diffraction pole figures.Moreover,{111} φ scans with χ at 55° reveal the abnormal distribution of Bragg diffractions.The extra intensity maxima in the pole figures shows that the process of twinning plays a dominating role during the growth process.It is suggested that the polarity of {111} facets emerged on (001) surface will affect the growth-twin nucleation at the initial stages of GaN growth on GaAs(001) substrates.It is proposed that twinning is prone to occurring on {111}B,N-terminated facets.采用同步辐射XRD极图法对低温MOCVD生长的GaN缓冲层薄膜进行了研究.极图研究表明,低温GaN 薄膜中除有正常结晶外还存在一次孪晶和二次孪晶.在χ固定为55°时的{111}φ扫描中发现了异常的Bragg衍射峰,表明GaN/GaAs(001)低温生长中孪晶现象非常明显.GaAs(001)表面上出现的{111}小面极性会在生长初期影响孪晶成核,实验结果表明孪晶更易在{111}B面即N面上成核.

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

分 类 号：TN304.055[电子电信—物理电子学]