p-Type Conductivity Control in ZnO Films Grown by Molecular-Beam Epitaxy

<jats:p>We report on the p-type conductivity control using N and Te codoping and thermal annealing in the ZnO films, heteroepitaxially grown on Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> substrates and homoepitaxially grown on ZnO substrates by molecular-beam epitaxy, respectively. The N and Te codoping and the homoepitaxy effectively reduce the background electron concentration in ZnO films due to the suppression of various defect generation, and the thermal annealing causes the conductivity conversion from n-type to p-type due to the activation of N-related defects and the annihilation of donor-type defects. The p-type conductivity with a hole concentration of 1.610<jats:sup>1</jats:sup><jats:sup>6</jats:sup> cm<jats:sup>-3</jats:sup> and a hole mobility of 16 cm<jats:sup>2</jats:sup>/Vsec is obtained in the ZnO:N+T film grown on the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> substrate and the p-type conductivity with a hole concentration of 4.010<jats:sup>1</jats:sup><jats:sup>6</jats:sup> cm<jats:sup>-3</jats:sup> and a hole mobility of 11 cm<jats:sup>2</jats:sup>/Vsec is obtained in the ZnO:N+Te film grown on the ZnO substrate.</jats:p>