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Influence of Te-Doping on Catalyst-Free VS InAs Nanowires.

ABSTRACT: We report on the growth of Te-doped catalyst-free InAs nanowires by molecular beam epitaxy on silicon (111) substrates. Changes in the wire morphology, i.e. a decrease in length and an increase in diameter have been observed with rising doping level. Crystal structure analysis based on transmission electron microscopy as well as X-ray diffraction reveals an enhancement of the zinc blende/(wurtzite+zinc blende) segment ratio if Te is provided during the growth process. Furthermore, electrical two-point measurements show that increased Te-doping causes a gain in conductivity. Two comparable growth series, differing only in As-partial pressure by about 1?×?10^-5?Torr while keeping all other parameters constant, were analyzed for different Te-doping levels. Their comparison suggests that the crystal structure is strongly affected and the conductivity gain is more distinct for wires grown at a comparably higher As-partial pressure.

SUBMITTER: Gusken NA

PROVIDER: S-EPMC6538743 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Influence of Te-Doping on Catalyst-Free VS InAs Nanowires.

Güsken Nicholas A NA Rieger Torsten T Mussler Gregor G Lepsa Mihail Ion MI Grützmacher Detlev D

Nanoscale research letters 20190528 1

We report on the growth of Te-doped catalyst-free InAs nanowires by molecular beam epitaxy on silicon (111) substrates. Changes in the wire morphology, i.e. a decrease in length and an increase in diameter have been observed with rising doping level. Crystal structure analysis based on transmission electron microscopy as well as X-ray diffraction reveals an enhancement of the zinc blende/(wurtzite+zinc blende) segment ratio if Te is provided during the growth process. Furthermore, electrical two ...[more]

PMID: 31140033

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