Achieving non-degenerate Zn3N2 thin films by near room temperature sputtering deposition

Zn3N2 thin films have been grown at different substrate temperatures by reactive magnetron sputtering in an ultrahigh vacuum chamber. It is demonstrated that low temperature deposition is beneficial for producing nondegenerate Zn3N2 thin films, in stark contrast to previously reported Zn3N2 with high electron concentrations. Elevating the growth temperature will increase the carrier concentration significantly. Analyses of defect concentrations based on the defect formation energies estimated from first-principles calculations indicate that all the native defects are not responsible for the high carrier concentration, whereas unintentional oxygen-on-nitrogen (ON+) and/or hydrogen interstitial (Hi+) defects act as dominant donors in Zn3N2 thin films. Moreover, the remarkable deposition temperature dependence of the carrier concentration in Zn3N2 thin films would be attributed to the Boltzmann distribution of oxygen and/or hydrogen impurities. These results could pave a general way for controlling the carrier concentration in nominally nondoped nitride semiconductors.Zn3N2 thin films have been grown at different substrate temperatures by reactive magnetron sputtering in an ultrahigh vacuum chamber. It is demonstrated that low temperature deposition is beneficial for producing nondegenerate Zn3N2 thin films, in stark contrast to previously reported Zn3N2 with high electron concentrations. Elevating the growth temperature will increase the carrier concentration significantly. Analyses of defect concentrations based on the defect formation energies estimated from first-principles calculations indicate that all the native defects are not responsible for the high carrier concentration, whereas unintentional oxygen-on-nitrogen (ON+) and/or hydrogen interstitial (Hi+) defects act as dominant donors in Zn3N2 thin films. Moreover, the remarkable deposition temperature dependence of the carrier concentration in Zn3N2 thin films would be attributed to the Boltzmann distribution of oxygen and/or hydrogen impurities. These results could pave a general way for controlling the carri...