Polytypoid structures in annealed In2O3–ZnO films

Abstract

Atomic-resolution Z-contrast images demonstrate unambiguously that the annealed, metalorganic chemical vapor deposition derived transparent ${\mathrm{In}}_{\mathrm{2}}{\mathrm{O}}_{\mathrm{3}}\mathrm{–ZnO}$ films have a polytypoid microstructure, consisting of ZnO slabs of variable width separated by single In–O octahedral layers. These In–O layers induce a polarity inversion in the two adjacent ZnO layers, which is reversed again by a mirror domain boundary inside each ZnO slab.