Arsenic doped p-type zinc oxide films grown by radio frequency magnetron sputtering

As-doped ZnO films were grown by the radio frequency magnetron sputtering method. As the substrate temperature during growth was raised above similar to 400 degrees C, the films changed from n type to p type. Hole concentration and mobility of similar to 6 X 10(17) cm(-3) and similar to 6 cm(2) V-1 s(-1) were achieved. The ZnO films were studied by secondary ion mass spectroscopy, x-ray photoelectron spectroscopy (XPS), low temperature photoluminescence (PL), and positron annihilation spectroscopy (PAS). The results were consistent with the As-Zn-2V(Zn) shallow acceptor model proposed by Limpijumnong et al. [Phys. Rev. Lett. 92, 155504 (2004)]. The results of the XPS, PL, PAS, and thermal studies lead us to suggest a comprehensive picture of the As-related shallow acceptor formation. (c) 2009 American Institute of Physics. [doi:10.1063/1.3236578]