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Strain Relaxation in GaSb/GaAs(111)A Heteroepitaxy Using Thin InAs Interlayers.

ABSTRACT: We have systematically studied the strain relaxation processes in GaSb heteroepitaxy on GaAs(111)A using thin InAs interlayers. The growth with 1 ML- and 2 ML-InAs leads to formation of an InAsSb-like layer, which induces tensile strain in GaSb films, whereas the GaSb films grown with thicker InAs layers (?3 ML) are under compressive strain. As the InAs thickness is increased above 5 ML, the insertion of the InAs layer becomes less effective in the strain relaxation, leaving residual strain in GaSb films. This leads to the elastic deformation of the GaSb lattice, giving rise to the increase in the peak width of X-ray rocking curves.

SUBMITTER: Ohtake A

PROVIDER: S-EPMC6643550 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Strain Relaxation in GaSb/GaAs(111)A Heteroepitaxy Using Thin InAs Interlayers.

Ohtake Akihiro A Mano Takaaki T Mitsuishi Kazutaka K Sakuma Yoshiki Y

ACS omega 20181116 11

We have systematically studied the strain relaxation processes in GaSb heteroepitaxy on GaAs(111)A using thin InAs interlayers. The growth with 1 ML- and 2 ML-InAs leads to formation of an InAsSb-like layer, which induces tensile strain in GaSb films, whereas the GaSb films grown with thicker InAs layers (≥3 ML) are under compressive strain. As the InAs thickness is increased above 5 ML, the insertion of the InAs layer becomes less effective in the strain relaxation, leaving residual strain in G ...[more]

PMID: 31458215

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