Atomic structure of misfit dislocations in nonpolar ZnO/Al2O3 heterostructures

Abstract

Understanding dislocation core structures at the atomic level is of significant theoretical and technological importance because of the role dislocations play in the electronic/optical properties of materials. In this paper, we report our aberration-corrected scanning transmission electron microscopy study on misfit dislocation core structures at non-polar (112¯0)ZnO/(11¯02)Al2O3 (a-ZnO/r-Al2O3) interface. The atomic configuration of the core structure is found to be closely related to the preferred interfacial bonding configuration. A significant number of these misfit dislocations have undergone a core structure modification involving the incorporation of Zn in the Al2O3 side of the dislocation.