High Al-content AlInGaN epilayers with different thicknesses grown on GaN/sapphire templates
High Al-content AlInGaN epilayers with different thicknesses grown on GaN/sapphire templates
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DOI：
10.1016/j.apsusc.2008.09.046
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发表时间：
2008-12
影响因子：
6.7
通讯作者：
J. Shang;Bing Zhang;Chao-Min Wu;L. Cai;J. Y. Zhang;J. Yu;Qingtao Wang
中科院分区：
文献类型：
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作者：
J. Shang;Bing Zhang;Chao-Min Wu;L. Cai;J. Y. Zhang;J. Yu;Qingtao Wang
采用金属有机物化学气相沉积（MOCVD）方法在GaN/蓝宝石模板上生长了不同厚度的高Al含量的AlInGaN外延层，研究了其结构和光学性质。获得了Al、Ga、In含量沿生长方向沿着逐渐演化的直接证据。当薄膜厚度超过一定值时，开始形成具有恒定元素含量的AlInGaN外延层。这些结果也支持了蓝移和分裂的光致发光（PL）峰。对于最薄的外延层，表面的特点是与螺纹位错（TD），这表明一个螺旋生长模式的露头。随着厚度的增加，台阶流生长模式和V形坑，并终止于坑的步骤。
We studied the structural and optical properties of high Al-content AlInGaN epilayers with different thicknesses grown on GaN/sapphire templates by metalorganic chemical vapor deposition (MOCVD). Direct evidences of the gradual evolution of the content of Al, Ga and In along the growth direction were obtained. When the film thickness was over a certain value, however, the AlInGaN epilayer with constant element contents began to form. These results were also supported by the blue shift and splitting of the photoluminescence (PL) peak. For the thinnest epilayer, the surface was featured with outcrops of threading dislocations (TDs) which suggested a spiral growth mode. With increase in thickness, step-flow growth mode and V-shaped pits were observed, and the steps terminated at the pits.