Growth and photoluminescence characteristics of ZnO tripods

Abstract

Hexagonal and preferentially oriented three-dimensional ZnO tripods have been grown on p -Si [100] substrates by a simple vapor-solid technique without using any catalysts. The tripodal-core growth route involves the formation of a hexagonal disk with [0002] larger surfaces. The tripods show irreversible shape transformation to tetrapods at higher temperature and prolonged growth time. Temperature-dependent photoluminescence characteristics of ZnO tripods have been investigated in the range from 10 to 300 K. Multiple LO phonon-assisted emissions associated with both bound and free excitons are observed for tripods, the origin of which have been explained by Permogorov's theory for II-VI semiconductors. © 2009 American Institute of Physics.