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Title: A Study of Dopant Incorporation in Te - doped GaAsSb Nanowires using a Combination of XPS/UPS, and C-AFM/SKPM
We report the first study on doping assessment in Te-doped GaAsSb nanowires (NWs) with variation in Gallium Telluride (GaTe) cell temperature, using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), conductive-atomic force microscopy (C-AFM), and scanning Kelvin probe microscopy (SKPM). The NWs were grown using Ga-assisted molecular beam epitaxy with a GaTe captive source as the dopant cell. Te-incorporation in the NWs was associated with a positive shift in the binding energy of the 3d shells of the core constituent elements in doped NWs in the XPS spectra, a lowering of the work function in doped NWs relative to undoped ones from UPS spectra, a significantly higher photoresponse in C-AFM and an increase in surface potential of doped NWs observed in SKPM relative to undoped ones. The carrier concentration of Te-doped GaAsSb NWs determined from UPS spectra are found to be consistent with the values obtained from simulated I-V characteristics. Thus, these surface analytical tools, XPS/UPS and C-AFM/SKPM, that do not require any sample preparation are found to be powerful characterization techniques to analyze the dopant incorporation and carrier density in homogeneously doped NWs.  more » « less
Award ID(s):
1832117
PAR ID:
10274157
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Scientific report
Volume:
11
ISSN:
0112-2398
Page Range / eLocation ID:
8329
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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