Cl Doping Effect by Thermal Treatment with KC1 for ZnO Single Crystals

摘要

We investigated the optical and electrical properties of ZnO single crystals coated with KC1 by examining the photoluminescence (PL) at 9 K and the temperature dependence of the carrier concentration. The band-edge PL intensity of the KCl-coated sample was much larger than that of the uncoated sample. Moreover, a substantial increase in Hall electrons was observed in the coated sample. X-ray photoelectron spectroscopy revealed bonding between chlorine and zinc atoms in the coated sample. Therefore, coating the surface of ZnO single crystals with KC1 enhances the donor concentration and improves the surface state.