Crystal Structure of In2O3(ZnO)(m) Superlattice Wires and Their Photoluminescence Properties

One-dimensional In2O3(ZnO)(m) superlattice wires were first synthesized on silicon substrates by evaporating a mixture of In and ZnO powders. The high-resolution transmission electron microscopy image indicates that the wires have a superlattice structure along their length, which consists of alternating stacks of an InO2- octahedral layer, as an inversion boundary, and an InO+(ZnO)(m) slab. Each slab is further separated by many triangular (zigzag) shape-contrast boundaries. They are secondary polarity inversion boundaries formed by 5-fold coordinated In and Zn atoms. The formation of such superlattice nanostructures is explained by the zigzag model. The PL properties of the superlattice nanostructures are discussed with regard to its temperature dependence for the first time.