p-Type zinc oxide thin films with c-axis orientation were prepared in N2O-O-2 atmosphere by an Al-N co-doping method using reactive magnetron sputtering. Secondary ion mass spectroscopy (SIMS) measurements indicate that as-grown ZnO films were co-doped with Al and N. Hall effect measurements show a dependence of types of conduction, carrier concentration and mobility of as-grown ZnO films on N2O partial pressure ratios. p-Type ZnO thin films deposited in a N2O partial ratio of 10% show the highest hole concentration of 1.1 x 10(17) cm(-3), the lowest resistivity of about 100 Omega cm, and a low mobility of 0.3 cm 2 V-1 s(-1). (c) 2004 Elsevier B.V. All rights reserved.