Stoichiometry and discommensuration on InxGa1-xAs/GaAs(001) reconstructed surfaces: A quantitative x-ray diffuse-scattering study

Citation
Y. Garreau et al., Stoichiometry and discommensuration on InxGa1-xAs/GaAs(001) reconstructed surfaces: A quantitative x-ray diffuse-scattering study, PHYS REV B, 58(24), 1998, pp. 16177-16185
Citations number
20
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B-CONDENSED MATTER
ISSN journal
01631829 → ACNP
Volume
58
Issue
24
Year of publication
1998
Pages
16177 - 16185
Database
ISI
SICI code
0163-1829(199812)58:24<16177:SADOIR>2.0.ZU;2-F
Abstract
A quantitative estimate of the In/Ga surface concentration ratio in ultrath in (In, Ga)As strained layers, grown by molecular-beam epitaxy on a GaAs(00 1) substrate, is obtained using grazing incidence x-ray diffraction and dif fuse-scattering measurements. The commensurate 2x3 reconstruction is interp reted as due to cation ordering in the surface unit cell, locking the surfa ce composition at the value In2/3Ga1/3As. Incommensurate 2xn reconstruction s with n<3 (n>3) are described in terms of indium-depleted (-enriched) surf ace layers characterized by a statistical distribution of faults in the ide al 2 x 3 atomic arrangement. Within a defined temperature range 450-490 deg rees C, a unique correspondence between the incommensurability parameter n and the indium surface fraction is established on the basis of a formulatio n of the diffuse scattering distribution. [S0163-1829(98)04648-7].