Atomic-resolution study of lattice distortions of buried In{sub x}Ga{sub 1{minus}x}As monolayers in GaAs(001)

Journal Article · Mon Nov 01 04:00:00 EST 1999 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.60.13612· OSTI ID:690746

Lee, T; Pillai, M R ^[1]; Woicik, J C ^[2]; Labanda, G; Lyman, P F; Barnett, S A ^[1]; Bedzyk, M J ^[1]

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1. Department of Materials Science and Engineering and Materials Research Center, Northwestern University, Evanston, Illinois 60208 (United States)
2. National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

X-ray standing wave measurements were used to study the strain in one monolayer of pseudobinary alloy In{sub x}Ga{sub 1{minus}x}As buried in GaAs(001) by molecular-beam epitaxy. The measured In position along the [001] direction exhibited a nearly linear dependence on the In concentration {ital x}, thus supporting the validity of macroscopic continuum elasticity theory at the one-monolayer limit. A random-cluster calculation using a valence force field was performed to explain microscopically the origin of the vertical expansion of the strained monolayer observed by the experiment. The calculated As-In-As bond angle and the positions of the first-nearest-neighbor As atoms of In suggest that the nearly linear dependence of the In height on the alloy composition is a combined result of the As-In-As bond bending and the local lattice distortion at the GaAs/In{sub x}Ga{sub 1{minus}x}As interface. The calculated In-As and Ga-As bond lengths were found to depend weakly on the In concentration, consistent with an earlier calculation for the case of a thick In{sub x}Ga{sub 1{minus}x}As film on GaAs(001) and the available x-ray absorption fine-structure data. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 690746
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 19 Vol. 60; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
ELASTICITY
GALLIUM ARSENIDES
INDIUM ARSENIDES
INDIUM COMPOUNDS
INTERFACES
LATTICE PARAMETERS
LAYERS
MOLECULAR BEAM EPITAXY
PLASTICITY
STANDING WAVES
STRAINS
X RADIATION