Atomic structure of prismatic stacking faults in nonpolar a-plane GaN epitaxial layers

Abstract

In this study, a-plane GaN was grown on r-plane sapphire by sidewall lateral epitaxial overgrowth. Prismatic stacking faults (PSFs) in the window region of the GaN layer were identified to have an atomic configuration similar to the model presented by Northrup [Appl. Phys. Lett. 72, 2316 (1998)], which was demonstrated by comparing high-angle annular dark-field scanning transmission electron microscopy images with the atomic configurations of the Drum model, the Amelinckx model, and simplified Northrup model, respectively. The Northrup PSF structure has been further confirmed by the scattering contrast analysis in transmission electron microscopy experiments.