Composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors

被引：38

作者：

Liu, B. ^{[1
]}

Zhang, R. ^{[1
]}

Zheng, J. G. ^{[2
]}

Ji, X. L. ^{[1
]}

Fu, D. Y. ^{[1
]}

Xie, Z. L. ^{[1
]}

Chen, D. J. ^{[1
]}

Chen, P. ^{[1
]}

Jiang, R. L. ^{[1
]}

Zheng, Y. D. ^{[1
]}

机构：

[1] Nanjing Univ, Sch Elect Sci & Engn, Nanjing Natl Lab Microstruct, Jiangsu Prov Key Lab Adv Photon & Elect Mat, Nanjing 210093, Peoples R China

[2] Univ Calif Irvine, Calif Inst Telecommun & Informat Technol, Irvine, CA 92697 USA

来源：

APPLIED PHYSICS LETTERS | 2011年 / 98卷 / 26期

基金：

高等学校博士学科点专项科研基金;

关键词：

SURFACE SEGREGATION; QUANTUM-WELLS; HETEROSTRUCTURES; DEVICES; ALLOYS; GROWTH; GAN;

D O I：

10.1063/1.3605681

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We report on the composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors (DBRs) grown on GaN template/alpha-Al2O3(0001) by metal organic chemical vapor deposition. The reciprocal space mapping contours reveal that these DBRs are coherently grown. Cross-section transmission electron microscopy image of the AlGaN/AlN DBRs and the energy-dispersive x-ray analysis indicate that an AlGaN layer with gradient Al composition is located between the Al0.4Ga0.6N and AlN layers along the [0001] direction. It is attributed to the fact that Ga atoms in AlGaN are pulled and segregated to the upper layer by the strain. The density of strain energy is estimated to reduce more than one order by forming this quasi-three-sublayer structure comparing to the designed bi-sublayer structure. (C) 2011 American Institute of Physics. [doi:10.1063/1.3605681]

引用

页数：3

共 22 条

[1] Two-dimensional electron gases induced by spontaneous and piezoelectric polarization charges in N- and Ga-face AlGaN/GaN heterostructures [J].