Analysis of Modified Williamson-Hall Plots on GaN Layers

Williamson Hall （W-H） analysis is often used to separate the lateral coherence length （LCL） broadening and dislocation broadening＂ on the ω-sean with a Lorentzian distribution. However, besides the LCL broadening and dislocation broadening, curvature also can broaden the w-scan peak. Usually, the w-scan can be described by a Pseudo-Voigt （P-V） function more precisely than a Lorentzian function. Based on the P-V fit peak profile, we modify the W-H plots. Both LCL broadening and curvature broadening can be eliminated from （OOl） ω-scans plots simultaneously, and a reliable tilt can be obtained. This method is a good complementary for the existing method, but is more convenient. Although we focuse on GaN layers, the results are applicable to a wide range of other materials having mosaic structures.