Ionization levels of As vacancies in as-grown GaAs studied by positron-lifetime spectroscopy

Journal Article · Thu Nov 14 23:00:00 EST 1991 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.44.10585· OSTI ID:5924481

Saarinen, K; Hautojaervi, P; Lanki, P ^[1]; Corbel, C ^[2]

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1. Laboratory of Physics, Helsinki University of Technology, 02150 Espoo (Finland)
2. Centre d'Etudes Nucleaires de Saclay, Institut National des Sciences et Techniques Nucleaires, 91191 Gif-sur-Yvette CEDEX (France)

The properties of the native monovacancy defects are systematically investigated by positron-lifetime measurements in {ital n}-type GaAs with carrier concentrations of {ital n}=10{sup 15--}10{sup 18} cm{sup {minus}3}. The native defects present two ionization levels at {ital E}{sub {ital C}}{minus}30 meV and {ital E}{sub {ital C}}{minus}140 meV. The first corresponds to a charge transition 1{minus}{r arrow}0 and the second to 0{r arrow}1+. The transitions are attributed to ionizations of As vacancy, which may be isolated or part of a complex. In a simple identification of the defect with {ital V}{sub As}, the ionization level at {ital E}{sub {ital C}}{minus}30 meV is attributed to the transition {ital V}{sub As}{sup {minus}}{r arrow}{ital V}{sub As}{sup 0} and the ionization level at {ital E}{sub {ital C}}{minus}140 meV to the transition {ital V}{sub As}{sup 0}{r arrow}{ital V}{sub As}{sup +}. The results show further that the configuration of {ital V}{sub As}{sup {minus}} is strongly relaxed inwards compared to the structure of {ital V}{sub As}{sup 0}.

• OSTI ID: 5924481
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 44:19; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

665300* -- Interactions Between Beams & Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ARSENIC COMPOUNDS
ARSENIDES
BEAMS
CHARGE TRANSPORT
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ENERGY LEVELS
EXCITED STATES
FERMI LEVEL
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
IONIZATION POTENTIAL
LEPTON BEAMS
LIFETIME
MATERIALS
N-TYPE CONDUCTORS
PARTICLE BEAMS
PNICTIDES
POINT DEFECTS
POSITRON BEAMS
RYDBERG STATES
SEMICONDUCTOR MATERIALS
SPECTROSCOPY
VACANCIES