Cross-sectional X-ray microdiffraction study of a thick AlN film grown on a trench-patterned AlN/α-Al2O3 template.

Abstract: X-ray microdiffraction (XRMD) measurements using the AlN and Bragg reflections were performed to determine the cross-sectional distribution of local residual strain and twisting of crystal domains for a thick AlN film grown on a trench-patterned AlN/α-Al2O3 template. The distribution of the strain components in the [0001] and directions, which are perpendicular to the trench lines, was strongly influenced by the presence of voids caused by the trench pattern. The strains in the and directions determined using the two Bragg reflections were found to be significantly different, and this was shown to be the result of twisting of the crystal domains about the [0001] axis under the influence of anisotropic shear stress in the prismatic planes. [Copyright &y& Elsevier]