Growth of epitaxial p-type ZnO thin films by codoping of Ga and N

Codoping of Ga and N was utilized to realize p-type conduction in ZnO films using rf magnetron sputtering. The films obtained at 550 degrees C on sapphire showed resistivity and hole concentrations of 38 Omega cm and 3.9x10(17) cm(-3), respectively. ZnO films also showed a p-type behavior on p-Si with better electrical properties. ZnO homojunctions synthesized by in situ deposition of Ga-N codoped p-ZnO layer on Ga doped n-ZnO layer showed clear p-n diode characteristics. Low temperature photoluminescence spectra of codoped films also revealed a dominant peak at 3.12 eV. The codoped films showed a dense columnar structure with a c-axis preferred orientation. (c) 2006 American Institute of Physics.