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

Journal Article · Mon Nov 15 04:00:00 EST 1999 · Phys. Rev. B

DOI:https://doi.org/10.1103/PhysRevB.60.13612· OSTI ID:943056

Lee, T -L; Pillai, M R; Woicik, J C; Labanda, G; Lyman, P F; Barnett, S A; Bedzyk, M J; NIST,

X-ray standing wave measurements were used to study the strain in one monolayer of pseudobinary alloy In{sub x}Ga{sub 1-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 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-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-x}As film on GaAs(001) and the available x-ray absorption fine-structure data.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: NSF; OUS; USDOE
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 943056
• Report Number(s): ANL/MSD/JA-37134
• Journal Information: Phys. Rev. B, Journal Name: Phys. Rev. B Journal Issue: 19 ; Nov. 15, 1999 Vol. 60; ISSN 1098-0121
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
BOND ANGLE
BOND LENGTHS
CHEMICAL BONDS
CRYSTAL LATTICES
DEFORMATION
GALLIUM ARSENIDES
INDIUM ARSENIDES
MOLECULAR BEAM EPITAXY
STRAINS