三甲基镓流量对GaN外延层和GaN缓冲层生长的影响

摘要

The GaN films were grown on different buffer layer that was deposited with different Trimethylgallium (TMGa) molar flow rate (FTMGa) by metalorganic vapor phase epitaxy (MOVPE). The samples were measured by X-ray Diffraction (XRD), and photoluminescence (PL). The results indicated that the GaN epilayer grown on buffer that was deposited under higher FTMGa condition had better quality. Atomic force microscopy (AFM) analysis of the bufferlayer showed that the growth model was different for various FTMGa growth condition. A model of GaN buffer layer growth process was proposed.%采用金属有机物气相外延法在蓝宝石衬底上生长了以GaN为缓冲层的GaN薄膜.研究了不同三甲基镓流量下所生长缓冲层对GaN外延层质量的影响.对样品采用X线双晶衍射法测试其结晶质量,光致发光法测试其光学特性.实验结果显示高三甲基镓流量下生长的缓冲层可以提高GaN外延层的质量.对缓冲层进行的原子力显微镜测试分析表明:不同三甲基镓流量会显著地影响缓冲层的生长模式.根据试验结果构造了一个GaN缓冲层的生长模型.