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Title: Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films

Abstract

In this paper we describe the use of electron backscatter diffraction (EBSD) mapping and electron channeling contrast imaging--in the scanning electron microscope--to study tilt, atomic steps and dislocations in epitaxial GaN thin films. We show results from a series of GaN thin films of increasing thickness and from a just coalesced epitaxial laterally overgrown GaN thin film. From our results we deduce that EBSD may be used to measure orientation changes of the order of 0.02 deg. , in GaN thin films. As EBSD has a spatial resolution of {approx_equal}20 nm, this means we have a powerful technique with which to quantitatively map surface tilt. We also demonstrate that electron channeling contrast images may be used to image tilt, atomic steps, and threading dislocations in GaN thin films.

Authors:
; ; ; ; ; ; ; ;  [1];  [2];  [3];  [3];  [3]
  1. SUPA, Department of Physics, University of Strathclyde, Glasgow G4 ONG, Scotland (United Kingdom)
  2. (Denmark)
  3. (United Kingdom)
Publication Date:
OSTI Identifier:
20976712
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevB.75.085301; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BACKSCATTERING; DISLOCATIONS; ELECTRON CHANNELING; ELECTRON DIFFRACTION; ELECTRONS; EPITAXY; GALLIUM NITRIDES; IMAGES; LAYERS; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR MATERIALS; SPATIAL RESOLUTION; SURFACES; THICKNESS; THIN FILMS

Citation Formats

Trager-Cowan, C., Sweeney, F., Trimby, P. W., Day, A. P., Gholinia, A., Schmidt, N.-H., Parbrook, P. J., Wilkinson, A. J., Watson, I. M., HKL TECHNOLOGY A/S, Majsmarken 1, Hobro, DK 9500, EPSRC National Centre for III-V Technologies, University of Sheffield, Department of Materials, University of Oxford, Oxford OX1 3PH, and SUPA, Institute of Photonics, University of Strathclyde, Glasgow G4 ONW, Scotland. Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.085301.
Trager-Cowan, C., Sweeney, F., Trimby, P. W., Day, A. P., Gholinia, A., Schmidt, N.-H., Parbrook, P. J., Wilkinson, A. J., Watson, I. M., HKL TECHNOLOGY A/S, Majsmarken 1, Hobro, DK 9500, EPSRC National Centre for III-V Technologies, University of Sheffield, Department of Materials, University of Oxford, Oxford OX1 3PH, & SUPA, Institute of Photonics, University of Strathclyde, Glasgow G4 ONW, Scotland. Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films. United States. doi:10.1103/PHYSREVB.75.085301.
Trager-Cowan, C., Sweeney, F., Trimby, P. W., Day, A. P., Gholinia, A., Schmidt, N.-H., Parbrook, P. J., Wilkinson, A. J., Watson, I. M., HKL TECHNOLOGY A/S, Majsmarken 1, Hobro, DK 9500, EPSRC National Centre for III-V Technologies, University of Sheffield, Department of Materials, University of Oxford, Oxford OX1 3PH, and SUPA, Institute of Photonics, University of Strathclyde, Glasgow G4 ONW, Scotland. Thu . "Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films". United States. doi:10.1103/PHYSREVB.75.085301.
@article{osti_20976712,
title = {Electron backscatter diffraction and electron channeling contrast imaging of tilt and dislocations in nitride thin films},
author = {Trager-Cowan, C. and Sweeney, F. and Trimby, P. W. and Day, A. P. and Gholinia, A. and Schmidt, N.-H. and Parbrook, P. J. and Wilkinson, A. J. and Watson, I. M. and HKL TECHNOLOGY A/S, Majsmarken 1, Hobro, DK 9500 and EPSRC National Centre for III-V Technologies, University of Sheffield and Department of Materials, University of Oxford, Oxford OX1 3PH and SUPA, Institute of Photonics, University of Strathclyde, Glasgow G4 ONW, Scotland},
abstractNote = {In this paper we describe the use of electron backscatter diffraction (EBSD) mapping and electron channeling contrast imaging--in the scanning electron microscope--to study tilt, atomic steps and dislocations in epitaxial GaN thin films. We show results from a series of GaN thin films of increasing thickness and from a just coalesced epitaxial laterally overgrown GaN thin film. From our results we deduce that EBSD may be used to measure orientation changes of the order of 0.02 deg. , in GaN thin films. As EBSD has a spatial resolution of {approx_equal}20 nm, this means we have a powerful technique with which to quantitatively map surface tilt. We also demonstrate that electron channeling contrast images may be used to image tilt, atomic steps, and threading dislocations in GaN thin films.},
doi = {10.1103/PHYSREVB.75.085301},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 8,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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