三甲基镓流量对GaN外延层和GaN缓冲层生长的影响(英文)

Effect of TMGa Molar Flow Rate of GaN Buffer on Subsequent GaN Epilayers and the Buffer Growth Model

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。

The GaN films were grown on different buffer layer that was deposited with dif fe rent Trimethylgallium (TMGa) molar flow rate (F TMGa) by metalorganic v apor phase epitaxy (MOVPE). The samples were measured by X ray Diffraction (XR D), and photoluminescence (PL). The results indicated that the GaN epilayer grown on bu ffer that was deposited under higher F TMGa condition had better qualit y. Atomic force microscopy (AFM) analysis of the buffer layer showed that the gr owth model was different for various F TMGa growth condition. A model o f GaN buffer layer growth process was proposed.