Defect reduction in nonpolar a-plane GaN films using in situ SiNx nanomask
Defect reduction in nonpolar a-plane GaN films using in situ SiNx nanomask
复制标题
DOI：
10.1063/1.2234841
复制
发表时间：
2006-07
影响因子：
4
通讯作者：
A. Chakraborty;Kwangchoong Kim;Feng Wu;J. Speck;S. Denbaars;U. Mishra
中科院分区：
文献类型：
--
作者：
A. Chakraborty;Kwangchoong Kim;Feng Wu;J. Speck;S. Denbaars;U. Mishra
我们报告使用原位氮化硅纳米掩模的缺陷减少在非极性a面GaN薄膜，生长的金属有机化学气相沉积。高分辨率的X射线衍射分析表明，有一个单调减少的半高宽，轴上和离轴，随着SiNx厚度的增加。原子力显微镜图像显示的均方根粗糙度和亚微米凹坑的密度显着下降。样品的横截面和平面透射电子显微镜显示，层错密度从8× 105 cm −1降低到3 × 105 cm −1，穿透位错密度从8× 1010 cm − 2降低到9 × 109 cm −2。室温下的光致发光测量结果表明，带边发射强度增加与SiNx层的插入，这表明在非辐射复合中心的减少。
We report on the use of in-situ SiNx nanomask for defect reduction in nonpolar a-plane GaN films, grown by metal-organic chemical vapor deposition. High-resolution x-ray diffraction analysis revealed that there was a monotonic reduction in the full width at half maximum, both on-axis and off-axis, with the increase in the SiNx thickness. Atomic force microscopy images revealed a significant decrease in the root-mean-square roughness and the density of submicron pits. Cross-section and plan-view transmission electron microscopy on the samples showed that the stacking fault density decreased from 8×105to3×105cm−1 and threading dislocation density decreased from 8×1010to9×109cm−2. Room temperature photoluminescence measurement revealed that the band-edge emission intensity increased with the insertion of the SiNx layer, which suggests reduction in the nonradiative recombination centers.