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Title: Curvature and bow of bulk GaN substrates

Abstract

We investigate the bow of free standing (0001) oriented hydride vapor phase epitaxy grown GaN substrates and demonstrate that their curvature is consistent with a compressive to tensile stress gradient (bottom to top) present in the substrates. The origin of the stress gradient and the curvature is attributed to the correlated inclination of edge threading dislocation (TD) lines away from the [0001] direction. A model is proposed and a relation is derived for bulk GaN substrate curvature dependence on the inclination angle and the density of TDs. The model is used to analyze the curvature for commercially available GaN substrates as determined by high resolution x-ray diffraction. The results show a close correlation between the experimentally determined parameters and those predicted from theoretical model.

Authors:
; ; ;  [1];  [1];  [2];  [2];  [3]
  1. Materials Department, UCSB, Santa Barbara, California 93106 (United States)
  2. (Russian Federation)
  3. Mechanical Engineering Department, UCSB, Santa Barbara, California 93106 (United States)
Publication Date:
OSTI Identifier:
22597663
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DENSITY; DISLOCATIONS; GALLIUM NITRIDES; HYDRIDES; INCLINATION; STRESSES; SUBSTRATES; VAPOR PHASE EPITAXY; X-RAY DIFFRACTION

Citation Formats

Foronda, Humberto M., Young, Erin C., Robertson, Christian A., Speck, James S., Romanov, Alexey E., Ioffe Physico-Technical Institute RAS, St. Petersburg 194021, ITMO University, St. Petersburg 197101, and Beltz, Glenn E. Curvature and bow of bulk GaN substrates. United States: N. p., 2016. Web. doi:10.1063/1.4959073.
Foronda, Humberto M., Young, Erin C., Robertson, Christian A., Speck, James S., Romanov, Alexey E., Ioffe Physico-Technical Institute RAS, St. Petersburg 194021, ITMO University, St. Petersburg 197101, & Beltz, Glenn E. Curvature and bow of bulk GaN substrates. United States. doi:10.1063/1.4959073.
Foronda, Humberto M., Young, Erin C., Robertson, Christian A., Speck, James S., Romanov, Alexey E., Ioffe Physico-Technical Institute RAS, St. Petersburg 194021, ITMO University, St. Petersburg 197101, and Beltz, Glenn E. 2016. "Curvature and bow of bulk GaN substrates". United States. doi:10.1063/1.4959073.
@article{osti_22597663,
title = {Curvature and bow of bulk GaN substrates},
author = {Foronda, Humberto M. and Young, Erin C. and Robertson, Christian A. and Speck, James S. and Romanov, Alexey E. and Ioffe Physico-Technical Institute RAS, St. Petersburg 194021 and ITMO University, St. Petersburg 197101 and Beltz, Glenn E.},
abstractNote = {We investigate the bow of free standing (0001) oriented hydride vapor phase epitaxy grown GaN substrates and demonstrate that their curvature is consistent with a compressive to tensile stress gradient (bottom to top) present in the substrates. The origin of the stress gradient and the curvature is attributed to the correlated inclination of edge threading dislocation (TD) lines away from the [0001] direction. A model is proposed and a relation is derived for bulk GaN substrate curvature dependence on the inclination angle and the density of TDs. The model is used to analyze the curvature for commercially available GaN substrates as determined by high resolution x-ray diffraction. The results show a close correlation between the experimentally determined parameters and those predicted from theoretical model.},
doi = {10.1063/1.4959073},
journal = {Journal of Applied Physics},
number = 3,
volume = 120,
place = {United States},
year = 2016,
month = 7
}
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