Effects of high-dose Mn implantation into ZnO grown on sapphire

摘要

ZnO films grown by pulsed-laser deposition on c-plane Al_(2)O_(3) substrates were annealed at temperatures up to 600℃ to produce n-type carrier concentrations in the range 7.5×10~(15)-1.5×10~(20) cm~(-3). After high-dose (3×10~(16) cm~(-2)) Mn implantation and subsequent annealing at 600℃, all the films show n-type carrier concentrations in the range 2-5×10~(20) cm~(-3) and room temperature hysteresis in magnetization loops. The saturation magnetization and coercivity of the implanted single-phase films were both strong functions of the initial anneal temperature, suggesting that carrier concentration alone cannot account for the magnetic properties of ZnO:Mn, and that factors such as crystalline quality and residual defects play a role.