Tuning the formation of p-type defects by peroxidation of CuAlO2 films

Abstract

p-type conduction of CuAlO2 thin films was realized by the rf sputtering method. Combining with Hall, X-ray photoelectron spectroscopy, energy dispersive spectrometer, and X-ray diffraction results, a direct link between the hole concentration, Cu vacancy (VCu), and interstitial oxygen (Oi) was established. It is shown that peroxidation of CuAlO 2 films may lead to the increased formation probability of acceptors (VCu and Oi), thus, increasing the hole concentration. The dependence of the VCu density on growth conditions was identified for providing a guide to tune the formation of p-type defects in CuAlO 2. Understanding the defect-related p-type conductivity of CuAlO 2 is essential for designing optoelectronic devices and improving their performance. © 2013 AIP Publishing LLC.