Table of Contents
ISRN Condensed Matter Physics
Volume 2012, Article ID 184023, 6 pages
http://dx.doi.org/10.5402/2012/184023
Research Article

A Comparative Study of Dislocations in HVPE GaN Layers by High-Resolution X-Ray Diffraction and Selective Wet Etching

GaN Lab, Ostendo Technologies, Inc., 12214 Plum Orchard Drive, Silver Spring, MD 20783, USA

Received 18 June 2012; Accepted 31 July 2012

Academic Editors: A. Oyamada, M.-H. Phan, and H.-D. Yang

Copyright © 2012 Vladimir Ivantsov and Anna Volkova. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

It has been shown during the present study that the E-etching at elevated temperatures can be adopted for the dislocation etching in hydride vapor-phase epitaxy (HVPE) GaN layers. It has been found that the X-ray diffraction (XRD) evaluation of the dislocation density in the thicker than 6 𝜇m epilayers using conventional Williamson-Hall plots and Dunn-Koch equation is in an excellent agreement with the results of the elevated-temperature E-etching. The dislocation distribution measured for 2-inch GaN-on-sapphire substrate suggests strongly the influence of the inelastic thermal stresses on the formation of the final dislocation pattern in the epilayer.