中国物理B ›› 2017, Vol. 26 ›› Issue (4): 47801-047801.doi: 10.1088/1674-1056/26/4/047801
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
Qing-Jun Xu(徐庆君), Bin Liu(刘斌), Shi-Ying Zhang(张士英), Tao Tao(陶涛), Zi-Li Xie(谢自力), Xiang-Qian Xiu(修向前), Dun-Jun Chen(陈敦军), Peng Chen(陈鹏), Ping Han(韩平), Rong Zhang(张荣), You-Dou Zheng(郑有炓)
Qing-Jun Xu(徐庆君)1,2, Bin Liu(刘斌)1, Shi-Ying Zhang(张士英)1,2, Tao Tao(陶涛)1, Zi-Li Xie(谢自力)1, Xiang-Qian Xiu(修向前)1, Dun-Jun Chen(陈敦军)1, Peng Chen(陈鹏)1, Ping Han(韩平)1, Rong Zhang(张荣)1, You-Dou Zheng(郑有炓)1
摘要:
Structural characteristics of Al0.55Ga0.45N epilayer were investigated by high resolution x-ray diffraction (HRXRD) and transmission electron microscopy (TEM); the epilayer was grown on GaN/sapphire substrates using a high-temperature AlN interlayer by metal organic chemical vapor deposition technique. The mosaic characteristics including tilt, twist, heterogeneous strain, and correlation lengths were extracted by symmetric and asymmetric XRD rocking curves as well as reciprocal space map (RSM). According to Williamson-Hall plots, the vertical coherence length of AlGaN epilayer was calculated, which is consistent with the thickness of AlGaN layer measured by cross section TEM. Besides, the lateral coherence length was determined from RSM as well. Deducing from the tilt and twist results, the screw-type and edge-type dislocation densities are 1.0×108 cm-2 and 1.8×1010 cm-2, which agree with the results observed from TEM.
中图分类号: (III-V semiconductors)