中国物理B ›› 2014, Vol. 23 ›› Issue (4): 47804-047804.doi: 10.1088/1674-1056/23/4/047804
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
曹荣涛, 许晟瑞, 张进成, 赵一, 薛军帅, 哈微, 张帅, 崔培水, 温慧娟, 陈兴
Cao Rong-Tao (曹荣涛), Xu Sheng-Rui (许晟瑞), Zhang Jin-Cheng (张进成), Zhao Yi (赵一), Xue Jun-Shuai (薛军帅), Ha Wei (哈微), Zhang Shuai (张帅), Cui Pei-Shui (崔培水), Wen Hui-Juan (温慧娟), Chen Xing (陈兴)
摘要: Nonpolar (112 0) GaN films are grown on the etched a-plane GaN substrates via metalorganic vapor phase epitaxy. High-resolution X-ray diffraction analysis shows great decreases in the full width at half maximum of the samples grown on etched substrates compared with those of the sample without etching, both on-axis and off-axis, indicating the reduced dislocation densities and improved crystalline quality of these samples. The spatial mapping of the E2 (high) phonon mode demonstrates the smaller line width with a black background in the wing region, which testifies the reduced dislocation densities and enhanced crystalline quality of the epitaxial lateral overgrowth areas. Raman scattering spectra of the E2 (high) peaks exhibit in-plane compressive stress for all the overgrowth samples, and the E2 (high) peaks of samples grown on etched substrates shift toward the lower frequency range, indicating the relaxations of in-plane stress in these GaN films. Furthermore, room temperature photoluminescence measurement demonstrates a significant decrease in the yellow-band emission intensity of a-plane GaN grown on etched templates, which also illustrates the better optical properties of these samples.
中图分类号: (III-V semiconductors)