We report the effect of basal-plane stacking faults (BSFs) on X-ray diffraction (XRD) of non-polar (1120) a-plane GaN films with different SiNxinterlayers. Complete SiNxcoverage and increased three-dimensional (3D) to two-dimensional (2D) transition stages substantially reduce BSF density. It was revealed that the Si-doping profile in the Sidoped GaN layer was unaffected by the introduction of a SiNxinterlayer. The smallest in-plane anisotropy of the (1120) XRD ω-scan widths was found in the sample with multiple SiNxlayers, and this finding can be attributed to the relatively isotropic GaN mosaic resulting from the increase in the 3D-2D growth step. Williamson-Hall (WH) analysis of the (h0h0) series of diffractions was employed to determine the c-axis lateral coherence length (LCL) and to estimate the mosaic tilt. The c-axis LCLs obtained from WH analyses of the present study’s representative a-plane GaN samples were well correlated with the BSFrelated results from both the off-axis XRD ω-scan and transmission electron microscopy (TEM). Based on WH and TEM analyses, the trends in BSF densities were very similar, even though the BSF densities extracted from LCLs indicated that the values were reduced by a factor of about twenty.
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Electronic, Optical and Magnetic Materials