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Title: Depth dependence of defect density and stress in GaN grown on SiC

Abstract

We report high resolution x-ray diffraction studies of the relaxation of elastic strain in GaN grown on SiC(0001). The GaN layers were grown with thickness ranging from 0.29 to 30 {mu}m. High level of residual elastic strain was found in thin (0.29 to 0.73 {mu}m thick) GaN layers. This correlates with low density of threading screw dislocations of 1-2x10{sup 7} cm{sup -2}, observed in a surface layer formed over a defective nucleation layer. Stress was found to be very close to what is expected from thermal expansion mismatch between the GaN and SiC. A model based on generation and diffusion of point defects accounts for these observations.

Authors:
; ; ; ;  [1];  [2];  [2];  [2]
  1. Department of Electrical and Computer Engineering, University of Delaware, 140 Evans Hall, Newark, Delaware 19716 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20787719
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 98; Journal Issue: 12; Other Information: DOI: 10.1063/1.2141651; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GALLIUM NITRIDES; LAYERS; NUCLEATION; POINT DEFECTS; SCREW DISLOCATIONS; SEMICONDUCTOR MATERIALS; SILICON CARBIDES; STRAINS; STRESS RELAXATION; THERMAL EXPANSION; THICKNESS; X-RAY DIFFRACTION

Citation Formats

Faleev, N., Temkin, H., Ahmad, I., Holtz, M., Melnik, Yu., Department of Electrical Engineering, Texas Tech University, Lubbock, Texas 79409, Department of Physics, Texas Tech University, Lubbock, Texas 79409, and TDI Inc., 12241 Plum Orchard Drive, Silver Spring, Maryland 20904. Depth dependence of defect density and stress in GaN grown on SiC. United States: N. p., 2005. Web. doi:10.1063/1.2141651.
Faleev, N., Temkin, H., Ahmad, I., Holtz, M., Melnik, Yu., Department of Electrical Engineering, Texas Tech University, Lubbock, Texas 79409, Department of Physics, Texas Tech University, Lubbock, Texas 79409, & TDI Inc., 12241 Plum Orchard Drive, Silver Spring, Maryland 20904. Depth dependence of defect density and stress in GaN grown on SiC. United States. doi:10.1063/1.2141651.
Faleev, N., Temkin, H., Ahmad, I., Holtz, M., Melnik, Yu., Department of Electrical Engineering, Texas Tech University, Lubbock, Texas 79409, Department of Physics, Texas Tech University, Lubbock, Texas 79409, and TDI Inc., 12241 Plum Orchard Drive, Silver Spring, Maryland 20904. 2005. "Depth dependence of defect density and stress in GaN grown on SiC". United States. doi:10.1063/1.2141651.
@article{osti_20787719,
title = {Depth dependence of defect density and stress in GaN grown on SiC},
author = {Faleev, N. and Temkin, H. and Ahmad, I. and Holtz, M. and Melnik, Yu. and Department of Electrical Engineering, Texas Tech University, Lubbock, Texas 79409 and Department of Physics, Texas Tech University, Lubbock, Texas 79409 and TDI Inc., 12241 Plum Orchard Drive, Silver Spring, Maryland 20904},
abstractNote = {We report high resolution x-ray diffraction studies of the relaxation of elastic strain in GaN grown on SiC(0001). The GaN layers were grown with thickness ranging from 0.29 to 30 {mu}m. High level of residual elastic strain was found in thin (0.29 to 0.73 {mu}m thick) GaN layers. This correlates with low density of threading screw dislocations of 1-2x10{sup 7} cm{sup -2}, observed in a surface layer formed over a defective nucleation layer. Stress was found to be very close to what is expected from thermal expansion mismatch between the GaN and SiC. A model based on generation and diffusion of point defects accounts for these observations.},
doi = {10.1063/1.2141651},
journal = {Journal of Applied Physics},
number = 12,
volume = 98,
place = {United States},
year = 2005,
month =
}
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  • Abstract not provided.