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

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)

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