Control of conduction type in Al- and N-codoped ZnO thin films

p-type ZnO thin films have been fabricated by an Al- and N-codoping technique at the growth temperature between 380 and 480 degrees C, as identified by the Hall measurement. At lower and higher temperatures, however, the samples are n type. The best p-type sample shows a resistivity and hole concentration of 24.5 Omega cm and 7.48x10(17) cm(-3) at room temperature, respectively. Spread resistance depth profile further shows the transition from n-type substrate to p-type ZnO through a clearly defined depletion region. Photoluminescence spectra also show low signal in deep level transition, indicating a low density of native defects. (c) 2005 American Institute of Physics.