This study systematically investigates the influence of antimony (Sb) species on the electrical properties of Sb-doped zinc oxide (SZO) thin films prepared by pulsed laser deposition in an oxygen-rich environment. The Sb species-related defects were controlled through a qualitative change in energy per atom by increasing the Sb content in the Sb2O3:ZnO-ablating target. By increasing the content of Sb2O3 (wt.%) in the target, Sb3+ became the dominant Sb ablation species in the plasma plume. Consequently, n-type conductivity was converted to p-type conductivity in the SZO thin films prepared using the ablating target containing 2 wt.% Sb2O3. The substituted Sb species in the Zn site (SbZn3+ and SbZn+) were responsible for forming n-type conductivity at low-level Sb doping. On the other hand, the Sb-Zn complex defects (SbZn-2VZn) contributed to the formation of p-type conductivity at high-level doping. The increase in Sb2O3 content in the ablating target, leading to a qualitative change in energy per Sb ion, offers a new pathway to achieve high-performing optoelectronics using ZnO-based p-n junctions.
Keywords: antimony species; antimony-doped ZnO; complex defect; oxygen-rich condition.