InAsSb/InAs: A type-I or a type-II band alignment

Journal Article · Sun Oct 15 04:00:00 EDT 1995 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.52.12039· OSTI ID:124754

Wei, S; Zunger, A ^[1]

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1. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

Using first-principles band-structure calculations we have studied the valence-band alignment of InAs/InSb, deducing also the offset at the InAs{sub 1{minus}{ital x}}Sb{sub {ital x}}/InAs{sub 1{minus}{ital y}}Sb{sub {ital y}} heterostructure. We find the following: (i) Pure InAs/InSb has a ``type-II broken gap`` alignment both with and without strain. (ii) For Sb-rich InAs{sub 1{minus}{ital x}}Sb{sub {ital x}}/InSb heterostructures, the unstrained band alignment is type II; both epitaxial strain and CuPt ordering enhance the type-II character in this Sb-rich limit. (iii) For As-rich InAs/InAs{sub 1{minus}{ital x}}Sb{sub {ital x}} heterostructures the top of the valence band is always on the alloy layer while the conduction-band minimum can be localized either on the alloy layer (type-I) or on the InAs layer (type-II), depending on the balance between concentration, strain, and degree of ordering/phase separation. In this case, epitaxial strain enhances the type-II character, while ordering enhances the type-I character. Our results are compared with recent experimental observations. We find that the type-I behavior noted for some As-rich InAs/InAs{sub 1{minus}{ital x}}Sb{sub {ital x}} interfaces and the type-II behavior noted in other such samples could be explained in terms of the dominance of ordering and strain effects, respectively.

• Research Organization: National Renewable Energy Laboratory
• DOE Contract Number: AC36-83CH10093
• OSTI ID: 124754
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 16 Vol. 52; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ELECTRONIC STRUCTURE
EPITAXY
HETEROJUNCTIONS
INDIUM ANTIMONIDES
INDIUM ARSENIDES
INTERFACES
STRAINS