Optical characterization of hierarchical ZnO structures grown with a simplified vapour transport method

Abstract

A new ZnO micro/nanostructure morphology in the form of micro-torches was grown in the family of ZnO hierarchical structures by a simplified thermal chemical vapour transport and condensation method using a vertical furnace. It is formed by two basic parts: a three-dimensional (3D) crystal base and one-dimensional (1D) nanorods nucleated from this base. Mechanisms of this micro/nanostructure growth are suggested to be governed by the change of the ZnO vapour supersaturation level during the crystal growth. Micro-Raman analysis demonstrates good crystal lattice quality, independent of the micro/nanostructure morphology. Differences in the luminescence characteristics inherent to the different parts of the micro/nanostructure are expected to be useful for the development of micro/nano-optoelectronic devices.