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  • A Study on the Effects of Gallium Droplet Consumption and Post Growth Annealing on Te- Doped GaAs Nanowire Proper-ties grown by Self-Catalyzed Molecular Beam Epitaxy
Title: A Study on the Effects of Gallium Droplet Consumption and Post Growth Annealing on Te- Doped GaAs Nanowire Proper-ties grown by Self-Catalyzed Molecular Beam Epitaxy
In this work, the effects of arsenic (As) flux used during gallium (Ga) seed droplet consumption and the post-growth annealing on the optical, electrical, and microstructural properties of self-catalyzed molecular beam epitaxially grown tellurium (Te)-doped GaAs nanowires (NWs) have been investigated using a variety of characterization techniques. NWs using the same amount of As flux for growth of the seed droplet consumption demonstrated reduced density of stacking faults at the NW tip with ~ 4-fold enhancement in the 4K photoluminescence (PL) in-tensity and increased single nanowire photocurrent over their higher As flux droplet consump-tion counterparts. Post-growth annealed NWs exhibited an additional low-energy PL peak at 1.31 eV that significantly reduced the overall PL intensity. The origin of this lower energy peak is as-signed to a photocarrier transition from the conduction band to the annealing assisted Te-induced complex acceptor state (TeAsVGa-). In addition, post-growth annealing demonstrated a detrimental impact on the electrical properties of the Te-doped GaAs NWs as revealed by suppressed single nanowire (SNW) and ensemble NW photocurrent with a consequent enhanced low-frequency noise level compared to as-grown doped NWs. This work demonstrates that each parameter in the growth space must be carefully examined to successfully grow self-catalyzed Te-doped NWs of high quality and is not a simple extension of the growth of corresponding intrinsic NWs.  more » « less
Award ID(s):
1832117
PAR ID:
10337514
Author(s) / Creator(s):
Editor(s):
Leonarda Francesca Liotta
Date Published:
Journal Name:
Catalysts
Volume:
12
ISSN:
2073-4344
Page Range / eLocation ID:
451
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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