Defect-related anisotropic surface micro-structures of nonpolar a-plane GaN epitaxial films

Abstract

The anisotropic surface etching behavior of nonpolar a-plane GaN (112̄0) epitaxial films, grown by pulsed laser deposition, was investigated experimentally by wet chemical etching.

Joint effect of miscut r-plane sapphire substrate and different nucleation layers on structural characteristics of non-polar a-plane GaN films

“…The anisotropy in crystalline quality (ACQ) is generally induced by the discrepancy in the in-plane growth rate along different directions. 27,28 In this study, ACQ is defined bywhere FWHM [11̄00] and FWHM [0001] are the XRC FWHM values measured along the [11̄00] and [0001] directions, respectively. FWHM [11̄00] − FWHM [0001] and ACQ as a function of the miscut angle for the two series a -plane GaN film samples are plotted in Fig.…”

“…The anisotropy in crystalline quality (ACQ) is generally induced by the discrepancy in the in-plane growth rate along different directions. 27,28 In this study, ACQ is defined by…”

Non-Polar Gallium Nitride for Photodetection Applications: A Systematic Review

“…It should be noted that the grain/terrace size distributions and the surface roughness of the non-polar GaN-based photodetector played a huge role in the performance of the device. In addition, it was reported that AFM analysis could be further utilized to confirm the defect densities [31,78]. In other words, the screw dislocation had an impact on the surface, whereby these dislocations could generate a tension tangential to the surface, leading to surface depressions that prevailed the surface [31,79,80].…”