Photoluminescence Study of the Interface of Nanocrystalline ZnO/Amorphous ZnO

Abstract

We studied the growth process of nanocrystalline ZnO which grown in amorphous ZnO by photoluminescence (PL). In this process, we found a new visible emission band, the visible emission intensity increased quickly at first, then decreased exponentially, while the peaks energy has a red shift from 583nm to 615nm along with the increasing reaction temperature. The results indicate this visible emission band correlate with the nanocrystalline ZnO/amorphous ZnO interface. The interface was polarized by the activated amorphous ZnO acts with the nanocrystalline ZnO surface, thus charge carrier was self-trapped on the nanocrystalline ZnO surface and emitted visible PL by recombination. We studied the changes rule of the nanocrystalline ZnO / amorphous ZnO interface by the characteristic of visible emission.