Current-voltage characteristics of silicon-doped GaAs nanowhiskers with a protecting AlGaAs coating overgrown with an undoped GaAs layer

Journal Article · Sat May 15 04:00:00 EDT 2010 · Semiconductors

DOI:https://doi.org/10.1134/S1063782610050118· OSTI ID:21562301

Dementyev, P A; Samsonenko, Yu B; Cirlin, G E; Titkov, A N ^[1]

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1. Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

A technique for measurement of longitudinal current-voltage characteristics of semiconductor nanowhiskers remaining in contact with the growth surface is suggested. The technique is based on setting up a stable conductive contact between the top of a nanowhisker and the probe of an atomic-force microscope. It is demonstrated that, as the force pressing the probe against the top of the nanowhisker increases, the natural oxide layer covering the top is punctured and a direct contact between the probe and the nanowhisker body is established. In order to prevent nanowhiskers from bending and, ultimately, breaking, they need to be somehow fixed in space. In this study, GaAs nanowhiskers were kept fixed by partially overgrowing them with a GaAs layer. To isolate nanowhiskers from the matrix they were embedded in, they were coated by a nanometer layer of AlGaAs. Doping of GaAs nanowhiskers with silicon was investigated. The shape of the current-voltage characteristics obtained indicates that introduction of silicon leads to p-type conduction in nanowhiskers, in contrast to n-type conduction in bulk GaAs crystals grown by molecular-beam epitaxy. This difference is attributed to the fact that the vapor-liquid-solid process used to obtain nanowhiskers includes a final stage of liquid-phase epitaxy, a characteristic of the latter being p-type conduction obtained in bulk GaAs(Si) crystals.

• OSTI ID: 21562301
• Journal Information: Semiconductors, Journal Name: Semiconductors Journal Issue: 5 Vol. 44; ISSN SMICES; ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
ATOMIC FORCE MICROSCOPY
CHALCOGENIDES
CRYSTAL GROWTH METHODS
CRYSTALS
CURRENTS
DOPED MATERIALS
ELEMENTS
EPITAXY
FLUIDS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GASES
LAYERS
LIQUID PHASE EPITAXY
LIQUIDS
MATERIALS
MICROSCOPY
MOLECULAR BEAM EPITAXY
MONOCRYSTALS
NANOSTRUCTURES
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
PROBES
SEMICONDUCTOR MATERIALS
SEMIMETALS
SILICON
SOLIDS
SURFACES
VAPORS
WHISKERS