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Strain relaxation in InAs heteroepitaxy on lattice-mismatched substrates.

ABSTRACT: Strain relaxation processes in InAs heteroepitaxy have been studied. While InAs grows in a layer-by-layer mode on lattice-mismatched substrates of GaAs(111)A, Si(111), and GaSb(111)A, the strain relaxation process strongly depends on the lattice mismatch. The density of threading defects in the InAs film increases with lattice mismatch. We found that the peak width in x-ray diffraction is insensitive to the defect density, but critically depends on the residual lattice strain in InAs films.

SUBMITTER: Ohtake A

PROVIDER: S-EPMC7067763 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Strain relaxation in InAs heteroepitaxy on lattice-mismatched substrates.

Ohtake Akihiro A Mano Takaaki T Sakuma Yoshiki Y

Scientific reports 20200312 1

Strain relaxation processes in InAs heteroepitaxy have been studied. While InAs grows in a layer-by-layer mode on lattice-mismatched substrates of GaAs(111)A, Si(111), and GaSb(111)A, the strain relaxation process strongly depends on the lattice mismatch. The density of threading defects in the InAs film increases with lattice mismatch. We found that the peak width in x-ray diffraction is insensitive to the defect density, but critically depends on the residual lattice strain in InAs films. ...[more]

PMID: 32165693

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