N -type, p-type and semi-insulating ZnO:N thin film growth by metal organic chemical vapor deposition with NH3 doping

Abstract

p -type, n-type and semi-insulating ZnO:N thin films were successfully grown by metal organic chemical vapor deposition on c-plane sapphire using diethyl zinc and O2 precursors, N2 carrier gas, and NH3 as dopant. NH3 flow rates were varied from 0.2% to 4% in the growth runs. The resulting films were characterized for their structural, optical, and electrical properties by scanning electron microscopy, x-ray diffraction (XRD), Raman spectroscopy, photoluminescence (PL), and Hall effect measurements. XRD show a single ZnO (002) peak; Raman data show the presence of ZnO:N modes at 275, 510, 575, and 645cm−1; and PL results show broad peaks at 480 and 600nm corresponding to deep N incorporation for all the samples. Hall effect show n-type films with carrier concentrations of 6.57×1018cm−3, p-type with carrier concentrations of 4.24×1014cm−3, and semi-insulating with resistivity on the order of 1.5×105Ωcm.