Preparation of p-type ZnO films by Al+N-codoping method

p-Type ZnO thin films with c-axis orientation have been prepared in N 2O+O 2 atmosphere on glass substrates by DC reactive magnetron sputtering, and with the Al+N-codoping technique, we have realized p-ZnO in the same conditions. Results showed that types of conduction and carrier density in codoped ZnO films were found to be dependent on the substrate temperatures. At 500°C, both Al+N-codoped p-type ZnO films and N-doped ones have the highest hole density of 1.1×10 17 and 6.7×10 14 cm −3, respectively. When the growth temperature is higher than 550°C, p-type ZnO films cannot be achieved using the Al+N-codoped method. It is difficult to achieve p-ZnO with both high hole concentration and high mobility by codoping, most likely due to the inherent defects of the AlN precipitates produced in codoping process.