P-type ZnO thin films prepared by plasma molecular beam epitaxy using radical NO

N-doped p-type Zno thin films were grown by plasma molecular beam epitaxy (P-MBE) on c-plane sapphire (Al2O3) using radical NO as oxygen source and nitrogen dopant. The reproducible ZnO thin films have maximum net hole concentration (N-A - N-D) of 1.2 x 10(18) cm(-3) and minimum resistivity or 9,36 Omega cm. The influence of N incorporation on the quality of the ZnO thin films was studied using X-ray diffraction and absorption spectra. The photoluminescence spectra at 77 K of p-type ZnO thin films are dominated by the emission from donor-acceptor pair recombination. The formation mechanism of p-type ZnO is explained by the optical emission spectra of radical N, and radical NO. (c) 2005 WILEY-VCH Verlag Gmbfl & Co. KWA, Weinheim.