Photoluminescence and electrical properties of N-implanted ZnO films

ZnO thin films deposited on glass substrate were implanted by 140 keV N ions at a dose of 2 × 1016/cm2 and were then annealed in vacuum for 1 h at different temperatures. Hall effect and photoluminescence (PL) measurements were performed to investigate the electrical and optical properties of the films. PL measurements reveal that N ion implantation can deteriorate the photoluminescence. The subsequent annealing leads to the increase of the luminescence. Hall effect measurements indicate that the N-implanted ZnO film annealed at 600 °C is still n-type and carrier concentration is as high as 6.67 × 1022 cm−3. Lattice mismatch and the high doping levels are responsible for the difficulty in fabrication of p-type ZnO thin films by high dose N ion implantation.