Mechanism of stress-driven composition evolution during hetero-epitaxy in a ternary AlGaN system

被引：31

作者：

He, Chenguang ^{[1
]}

Qin, Zhixin ^{[1
]}

Xu, Fujun ^{[1
]}

Zhang, Lisheng ^{[1
]}

Wang, Jiaming ^{[1
]}

Hou, Mengjun ^{[1
]}

Zhang, Shan ^{[1
]}

Wang, Xinqiang ^{[1
,2
]}

Ge, Weikun ^{[1
]}

Shen, Bo ^{[1
,2
]}

机构：

[1] Peking Univ, Sch Phys, State Key Lab Artificial Microstruct & Mesoscop, Beijing 100871, Peoples R China

[2] Collaborat Innovat Ctr Quantum Matter, Beijing 100084, Peoples R China

来源：

SCIENTIFIC REPORTS | 2016年 / 6卷

基金：

中国国家自然科学基金; 国家高技术研究发展计划(863计划);

关键词：

ELECTRON-MOBILITY TRANSISTORS; RELAXATION; SAPPHIRE; HETEROSTRUCTURES; FILMS;

D O I：

10.1038/srep25124

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Two AlGaN samples with different strain were designed to investigate mechanism of stress-driven composition evolution. It is discovered that AlGaN grown on AlN or (AlN/GaN superlattices (SLs))/GaN both consist of two distinct regions with different compositions: transition region and uniform region, which is attributed to the compositional pulling effect. The formation of the transition region is due to the partial stress release caused by the generation of misfit dislocations near the hetero-interface. And the Al composition in the uniform region depends on the magnitude of residual strain. The difference in relaxation degree is 80.5% for the AlGaN epilayers grown on different underlayers, leading to a large Al composition difference of 22%. The evolutionary process of Al composition along [0001] direction was investigated in detail.

引用

页数：5

共 22 条

[1] Characterization of different-Al-content AlxGa1-xN/GaN heterostructures and high-electron-mobility transistors on sapphire [J].