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Epitaxial ZnO thin films doped uniformly with nitrogen at 10 20 atoms/cm 3 were fabricated by pulsed laser ablation of a Zn-rich Zn 3 N 2 target. The films grown at 300°C and annealed at 600°C in O 2 showed p-type conductivity. Two acceptor levels at 105 and 224 meV were determined by temperature-dependent Hall and photoluminescence measurements of the p-type samples. Transmission electron microscopy studies revealed that the p-type ZnO films consist of 10-20 nm columnar grains with a high density of defects and grain boundaries that may facilitate the annihilation of native donors and the activation of acceptors during postdeposition annealing.