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Title: Photoelectrochemical etching measurement of defect density in GaN grown by nanoheteroepitaxy

Abstract

The density of dislocations in n-type GaN was measured by photoelectrochemical etching. A 10x reduction in dislocation density was observed compared to planar GaN grown at the same time. Cross-sectional transmission electron microscopy studies indicate that defect reduction is due to the mutual cancellation of dislocations with equal and opposite Burger's vectors. The nanoheteroepitaxy sample exhibited significantly higher photoluminescence intensity and higher electron mobility than the planar reference sample.

Authors:
; ; ; ;  [1]
  1. Center for High Technology Materials, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico 87106 (United States)
Publication Date:
OSTI Identifier:
20795808
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 9; Other Information: DOI: 10.1063/1.2197059; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHEMICAL VAPOR DEPOSITION; CRYSTAL GROWTH; DISLOCATIONS; ELECTRON MOBILITY; ETCHING; GALLIUM NITRIDES; LAYERS; NANOSTRUCTURES; PHOTOLUMINESCENCE; SEMICONDUCTOR MATERIALS; TRANSMISSION ELECTRON MICROSCOPY; VAPOR PHASE EPITAXY

Citation Formats

Ferdous, M.S., Sun, X.Y., Wang, X., Fairchild, M.N., and Hersee, S.D. Photoelectrochemical etching measurement of defect density in GaN grown by nanoheteroepitaxy. United States: N. p., 2006. Web. doi:10.1063/1.2197059.
Ferdous, M.S., Sun, X.Y., Wang, X., Fairchild, M.N., & Hersee, S.D. Photoelectrochemical etching measurement of defect density in GaN grown by nanoheteroepitaxy. United States. doi:10.1063/1.2197059.
Ferdous, M.S., Sun, X.Y., Wang, X., Fairchild, M.N., and Hersee, S.D. Mon . "Photoelectrochemical etching measurement of defect density in GaN grown by nanoheteroepitaxy". United States. doi:10.1063/1.2197059.
@article{osti_20795808,
title = {Photoelectrochemical etching measurement of defect density in GaN grown by nanoheteroepitaxy},
author = {Ferdous, M.S. and Sun, X.Y. and Wang, X. and Fairchild, M.N. and Hersee, S.D.},
abstractNote = {The density of dislocations in n-type GaN was measured by photoelectrochemical etching. A 10x reduction in dislocation density was observed compared to planar GaN grown at the same time. Cross-sectional transmission electron microscopy studies indicate that defect reduction is due to the mutual cancellation of dislocations with equal and opposite Burger's vectors. The nanoheteroepitaxy sample exhibited significantly higher photoluminescence intensity and higher electron mobility than the planar reference sample.},
doi = {10.1063/1.2197059},
journal = {Journal of Applied Physics},
number = 9,
volume = 99,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}
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