Effect of N2 flow during deposition on p-type ZnO film

In this study, the influence of a nitrogen source on p-type conductive ZnO films was studied. Rapid thermal oxidation was conducted to oxidize ZnN films and convert them to ZnO films. When an as-deposited ZnN film was prepared at a high nitrogen gas flow rate, the converted ZnO film possessed many acceptors and showed stable p-type conduction. This p-type conduction was attributed to the nitrogen gas flow providing many N-o states, which act as acceptors within the processed ZnO film. It was found that the as-deposited ZnN film prepared at a high nitrogen gas flow rate is oxidized slightly so that only a few nitrogen atoms were replaced by oxygen. The carrier concentration and mobility of the optimized oxidized ZnN film were 9.76x10(17)cm(-3) and 62.78cm(2)V(-1) s(-1), respectively. A good rectified current-voltage characteristic with a turn-on voltage of 3.65V was achieved for the optimized ZnO: N/ZnO junction. (C) 2017 The Japan Society of Applied Physics