White X-ray microdiffraction analysis of defects, strain and tilts in a free standing GaN film

• Published in: Physica Status Solidi (b) Vol. 245; no. 5; pp. 899 - 902
• Main Authors: Barabash, R. I., Ice, G. E., Haskell, B. A., Nakamura, Shuji, Speck, J. S., Liu, W.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.05.2008; WILEY‐VCH Verlag; Wiley
• Subjects: 61.05.cp; 68.55.−a; 81.05.Ea; 81.15.Kk; Condensed matter: structure, mechanical and thermal properties; Defects and impurities: doping, implantation, distribution, concentration, etc; Exact sciences and technology; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Optical microscopy; Misfit dislocations; Shear stress; Free-standing film; VPE; XRD; Microstructure; Gallium nitride; White radiation; Defects
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/pssb.200778579

A novel white‐beam microdiffraction analysis of defects, strains and tilts in a free standing m ‐plane GaN film grown via hydride vapor phase epitaxy is presented. It is shown that misfit dislocations are grouped within cell boundaries creating local lattice rotations (tilts) between the growing cells. Distribution of lattice rotations in the film is not homogeneous. Regions of large rotations are separated by low rotations regions. The dominating rotation axis is parallel [11$ \bar 2 $0] direction. High in plane shear stress component is observed along [0001]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)