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A synthesis of tower-like ZnO submicron- and nanostructures is performed by simply evaporating a mixture of Zn and Ga. Scanning electron microscopy and transmission electron microscopy observations revealed that the regular hexagonal tower-like structure is likely to be made up in a layer-by-layer fashion and consist of sheets.

Aligned ZnCdSe alloy nanostructures have been grown on GaAs (100) substrates using metalorganic chemical vapor deposition. Scanning electron microscopy observations find that they resemble nano-arrowheads in having three-blades, and their long axis is aligned along either the [11̅1] or the [111̅] direction of the substrate. Transmission electron microscopy shows that the blades of the nano-arrowhead have a (01̅13) twin relationship with each other and that their flat surface is close to (2̅110). Cathodoluminescence studies reveal that non-radiative recombination centers are localized at the twin boundaries. A four-step growth process, combining epitaxy, stacking fault generation, nanotetrapod nucleation, and vapor−liquid−solid growth, is suggested to understand the three-bladed morphology and alignment directions of the nano-arrowheads. [ABSTRACT FROM AUTHOR]

One-dimensional In2O3(ZnO)msuperlattice 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)mslab. 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. [ABSTRACT FROM AUTHOR]