Structure of GaAs(001) surfaces: The role of electrostatic interactions

Journal Article · Fri Jul 15 04:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.2015· OSTI ID:7198174

Northrup, J E ^[1]; Froyen, S ^[2]

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1. Xerox Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, California 94304 (United States)
2. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

We report first-principles total-energy calculations for the GaAs(001) surface. Our results indicate that the 2[times]4 reconstruction corresponds to the [beta]2(2[times]4) structure, which exhibits two As dimers in the top layer and a third As dimer in the third layer. This structure has a lower surface energy than the [beta](2[times]4) model, which has three As dimers in the top layer. We also find that a model recently proposed by Skala [ital et] [ital al]. [Phys. Rev. B [bold 48], 9138 (1993)] for the structure of the Ga-rich 4[times]2 phase is energetically unfavorable. From our results we conclude that electrostatic interactions between the charged building blocks of polar semiconductor surfaces play an important role in determining the equilibrium structure. We introduce a simple model for estimating these interactions.

• DOE Contract Number: AC02-83CH10093
• OSTI ID: 7198174
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:3; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
ARSENIC COMPOUNDS
ARSENIDES
DIMERS
ELECTROSTATICS
ENERGY
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
INTERACTIONS
PHASE TRANSFORMATIONS
PNICTIDES
STRUCTURAL MODELS
SURFACES