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Title: Surface diffusion effects on growth of nanowires by chemical beam epitaxy

Abstract

Surface processes play a large role in the growth of semiconductor nanowires by chemical beam epitaxy. In particular, for III-V nanowires the surface diffusion of group-III species is important to understand in order to control the nanowire growth. In this paper, we have grown InAs-based nanowires positioned by electron beam lithography and have investigated the dependence of the diffusion of In species on temperature, group-III and -V source pressure and group-V source combinations by measuring nanowire growth rate for different nanowire spacings. We present a model which relates the nanowire growth rate to the migration length of In species. The model is fitted to the experimental data for different growth conditions, using the migration length as fitting parameter. The results show that the migration length increases with decreasing temperature and increasing group-V/group-III source pressure ratio. This will most often lead to an increase in growth rate, but deviations will occur due to incomplete decomposition and changes in sticking coefficient for group-III species. The results also show that the introduction of phosphorous precursor for growth of InAs{sub 1-x}P{sub x} nanowires decreases the migration length of the In species followed by a decrease in nanowire growth rate.

Authors:
; ; ; ;  [1]
  1. Solid State Physics/The Nanometer Structure Consortium, Lund University, Box 118, S-221 00 Lund (Sweden)
Publication Date:
OSTI Identifier:
20982682
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 3; Other Information: DOI: 10.1063/1.2435800; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL GROWTH; DECOMPOSITION; ELECTRON BEAMS; EPITAXY; INDIUM ARSENIDES; INDIUM PHOSPHIDES; MIGRATION LENGTH; QUANTUM WIRES; SEMICONDUCTOR MATERIALS

Citation Formats

Persson, A. I., Froeberg, L. E., Jeppesen, S., Bjoerk, M. T., and Samuelson, L. Surface diffusion effects on growth of nanowires by chemical beam epitaxy. United States: N. p., 2007. Web. doi:10.1063/1.2435800.
Persson, A. I., Froeberg, L. E., Jeppesen, S., Bjoerk, M. T., & Samuelson, L. Surface diffusion effects on growth of nanowires by chemical beam epitaxy. United States. doi:10.1063/1.2435800.
Persson, A. I., Froeberg, L. E., Jeppesen, S., Bjoerk, M. T., and Samuelson, L. Thu . "Surface diffusion effects on growth of nanowires by chemical beam epitaxy". United States. doi:10.1063/1.2435800.
@article{osti_20982682,
title = {Surface diffusion effects on growth of nanowires by chemical beam epitaxy},
author = {Persson, A. I. and Froeberg, L. E. and Jeppesen, S. and Bjoerk, M. T. and Samuelson, L.},
abstractNote = {Surface processes play a large role in the growth of semiconductor nanowires by chemical beam epitaxy. In particular, for III-V nanowires the surface diffusion of group-III species is important to understand in order to control the nanowire growth. In this paper, we have grown InAs-based nanowires positioned by electron beam lithography and have investigated the dependence of the diffusion of In species on temperature, group-III and -V source pressure and group-V source combinations by measuring nanowire growth rate for different nanowire spacings. We present a model which relates the nanowire growth rate to the migration length of In species. The model is fitted to the experimental data for different growth conditions, using the migration length as fitting parameter. The results show that the migration length increases with decreasing temperature and increasing group-V/group-III source pressure ratio. This will most often lead to an increase in growth rate, but deviations will occur due to incomplete decomposition and changes in sticking coefficient for group-III species. The results also show that the introduction of phosphorous precursor for growth of InAs{sub 1-x}P{sub x} nanowires decreases the migration length of the In species followed by a decrease in nanowire growth rate.},
doi = {10.1063/1.2435800},
journal = {Journal of Applied Physics},
number = 3,
volume = 101,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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