Cathodoluminescence study of Te-doped ZnO microstructures grown by a vapour-solid process

Abstract

Sintering of a mixture of TeO_2 and ZnO powders under an Ar flux leads to the formation of elongated Te-doped ZnO nano- and microstructures on the sample surface. The growth of the structures occurs via a vapour-solid process. Cathodoluminescence (CL) and energy dispersive spectroscopy (EDS) measurements show an inhomogeneous incorporation of Te along the growth axis of the structures. An enhancement of the band edge emission upon Te doping is attributed to the passivation of oxygen vacancies by Te atoms, which reduces the deep energy level-related recombination path.