Reduction of dislocations in GaN epilayers using templated three-dimensional coherent nanoislands
Reduction of dislocations in GaN epilayers using templated three-dimensional coherent nanoislands
复制标题
使用模板化三维相干纳米岛减少 GaN 外延层中的位错
DOI：
10.1063/1.1926419
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发表时间：
2005
影响因子：
4
通讯作者：
H. Okumura
中科院分区：
文献类型：
--
作者：
K. Jeganathan;M. Shimizu;H. Okumura
采用分子束外延技术，在6 H-SiC（0001）衬底上生长了位错密度较低的GaN层。从热湿化学蚀刻和原子力显微镜确定的位错的密度表明，作为缓冲区的相干纳米岛的插入减少了从界面到GaN外延层的缺陷迁移。在相干纳米岛上生长的GaN层中位错密度急剧下降到107 cm-2，而在AlN缓冲层上生长的典型GaN层中位错密度为109 cm-2。
Low-dislocation-density GaN layers have been grown on 6H–SiC(0001) substrates by molecular-beam epitaxy using high-density (∼4×1011cm−2) self-assembled Stranski–Krastanov GaN nanoislands buffer. The density of dislocations determined from hot-wet chemical etching and atomic force microscopy show that the insertion of coherent nanoislands as a buffer reduces the defect migration from the interface to the GaN epitaxial layers. The dislocation density is dramatically dropped to ∼107cm−2 in GaN layers grown on coherent nanoislands as compared to ∼109cm−2 in the typical GaN layers grown on the AIN buffer.