An ab initio‐based approach to the adsorption behavior of In on InAs wetting layer grown on GaAs(001) substrate

Autor: Tomonori Ito, Kosuke Ogasawara, Toru Akiyama, Kohji Nakamura
Rok vydání: 2010
Předmět:
Zdroj: physica status solidi c. 8:245-247
ISSN: 1610-1642
1862-6351
DOI: 10.1002/pssc.201000501
Popis: The reconstructions and adsorption-desorption behavior of In adatom on InAs wetting layer grown on GaAs(001) substrate are investigated on the basis of first-principles pseudopotential calculations. The surface phase diagrams, which are obtained by comparing the adsorption energy with gas-phase chemical potential, demonstrate that the entity of InAs/GaAs interface crucially affects the relative stability between α2(2×4) and β2(2×4) structures which appear under growth conditions. Exploring the adsorption sites for an In adatom on β2(2×4) also reveals that a large number of adsorption sites on InAs wetting layer emerge due to the InAs/GaAs interface as well as the lattice constraint from GaAs substrate. Furthermore, the calculated energy barrier for the migration of In adatom on InAs wetting layer (0.4 eV) is found to be much lower than that on InAs(001) surface (0.8 eV). These results obtained imply that both the lattice constraint and the InAs/GaAs interface are crucial to understand the growth processes of InAs on the wetting layer. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Databáze: OpenAIRE
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