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Influence of stress in GaN crystals grown by HVPE on MOCVD-GaN/6H-SiC substrate.

ABSTRACT: GaN crystals without cracks were successfully grown on a MOCVD-GaN/6H-SiC (MGS) substrate with a low V/III ratio of 20 at initial growth. With a high V/III ratio of 80 at initial growth, opaque GaN polycrystals were obtained. The structural analysis and optical characterization reveal that stress has a great influence on the growth of the epitaxial films. An atomic level model is used to explain these phenomena during crystal growth. It is found that atomic mobility is retarded by compressive stress and enhanced by tensile stress.

SUBMITTER: Zhang L

PROVIDER: S-EPMC3935196 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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