Structural, optical and electrical properties of co-sputtered p-type ZnO:Cu thin-films

Abstract

P-type Cu-doped zinc oxide thin-films were successfully obtained by co-sputtering method at 300 °C. XRD, FESEM and EDS were utilized for structural and morphological studies. As-deposited films showed wurtzite hexagonal structure with c-axis preferential orientation. Crystallite size of the films was approximately 30 nm. Optical characterization of the layers was carried out by UV–Vis. and PL spectroscopy. The layers have about 3.3 eV band gap. The crystal quality remained relatively intact by doping, especially in lower doped level. The Cu dopants occupied Zn vacancies and repaired the crystal structure. Electrical tests, including Hall and Seebeck measurements, and I-V characterization, proved that the p-type ZnO with the hole density of 2.604 × 1015 1/cm3 was developed. Its mobility was 0.286 cm2/Ω A s.