Controlled bipolar doping in Cu3N (100) thin films

摘要

We have fabricated insulating, p- and n-type CuN(100) films on SrTiO(100) by plasma assisted molecular beam epitaxy. By controlling the Cu/N flux rate, p-type doping with 10–10cm in Cu-poor condition and n-type doping with 10–10cm in N-poor condition were obtained without introducing foreign species. Together with formation of insulating CuN films with an optical absorption coefficient of ∼10cm in the photon energy above ∼2.2 eV and an estimated indirect bandgap of ∼1.3 eV, the bipolar doping in CuN films would be promising for solar energy conversion applications.