Relationships between the band gaps of the zinc-blende and wurtzite modifications of semiconductors

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

DOI:https://doi.org/10.1103/PhysRevB.50.2715· OSTI ID:7276406

Yeh, C; Wei, S; Zunger, A ^[1]

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

While the direct band gaps of wurtzite (W) and zinc-blende (ZB) structures are rather similar, the W and ZB gaps can differ enormously (e.g., [similar to]1 eV in SiC) in indirect gap materials. This large difference is surprising given that the structural difference between wurtzite and zinc blende starts only in the third neighbor and that [ital total] energy differences are only [similar to]0.01 eV/atom. We show that zinc-blende compounds can be divided into five types (I--V) in terms of the order of their [Gamma][sub 1[ital c]], [ital X][sub 1[ital c]], and [ital L][sub 1[ital c]] levels and that this decides the character (direct, indirect, pseudodirect) of the wurtzite band gap. The observation of small [ital E][sub [ital g]][sup W][minus][ital E][sub [ital g]][sup ZB] differences in direct band-gap systems ( type II,'' e.g., ZnS), and large differences in indirect gap systems ( type IV,'' e.g., SiC) are explained. We further show that while both type-III systems (e.g., AIN) and type-V systems (e.g., GaP) have an indirect gap in the zinc-blende form, their wurtzite form will have direct and pseudodirect band gaps, respectively. Furthermore, a direct-to-pseudodirect transition is predicted to occur in type-I (e.g., GaSb) systems.

• DOE Contract Number: AC36-83CH10093
• OSTI ID: 7276406
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:4; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606* -- Other Materials-- Physical Properties-- (1992-)
ALUMINIUM COMPOUNDS
ALUMINIUM NITRIDES
CHALCOGENIDES
ELECTRONIC STRUCTURE
ENERGY
ENERGY GAP
GALLIUM COMPOUNDS
GALLIUM PHOSPHIDES
INORGANIC PHOSPHORS
MATERIALS
NITRIDES
NITROGEN COMPOUNDS
PHOSPHIDES
PHOSPHORS
PHOSPHORUS COMPOUNDS
PNICTIDES
SEMICONDUCTOR MATERIALS
SULFIDES
SULFUR COMPOUNDS
ZINC COMPOUNDS
ZINC SULFIDES