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Indexed by:期刊论文

Date of Publication:2017-06-01

Journal:CRYSTAL GROWTH & DESIGN

Included Journals:SCIE、EI、Scopus

Volume:17

Issue:6

Page Number:3411-3418

ISSN No.:1528-7483

Abstract:The indium (In) incorporation induced morphological evolution and strain relaxation of high In content InGaN epilayers grown by metal-organic chemical vapor deposition (MOCVD) were investigated. With the decrease of growth temperature from 753 to 627 degrees C, In incorporation increases from 0.10 to 0.42, and the surface morphology evolves from initially mound-like three-dimensional surface roughness to progressive smoothness. Such morphology evolution mechanism can be well accounted for by a self-regulating model of islands' proportions considering both strain relaxation and In surfactant-effect comprehensively. Additionally, the strain relaxation and microstructural defects of such InGaN epilayers were investigated by X-ray diffraction reciprocal space mapping and cross-sectional transmission electron microscopy, respectively. It is found that, with the increase of In content, plastic relaxation via generating random stacking faults along with the surface sawtooth roughening becomes a more important strain relaxation mechanism. The presented results contribute to, better understanding of the microscopic nature and growth mechanisms of high In content InGaN epilayers grown by MOCVD.