Properties of epitaxial ZnO:P films

Epitaxial ZnO:P films have been produced by annealing ZnP 2 substrates in atomic oxygen and characterized by X-ray diffraction, atomic force microscopy, Hall effect measurements, X-ray photoelectron spectroscopy, and photoluminescence measurements. The X-ray diffraction patterns of the films showed the 002 peak, indicating that their c axis was normal to the substrate surface. According to the Hall effect data, the layers were p-type, with a resistivity of ∼20 Ω cm, hole mobility of ∼9 cm 2 /(V s), and hole concentration of ∼7.8 × 10 17 cm −3 . The photoluminescence spectra of the ZnO:P films showed a peak at 3.356 eV (neutral acceptor bound exciton). Our results indicate that the ZnO:P films contain the P Zn -2V Zn defect complex as a shallow acceptor responsible for their p -type conductivity.