Nitrogen-doped ZnO films were grown by metal organic chemical vapor deposition using diallylamine as the doping source. Secondary ion mass spectrometry measurements attest for the incorporation of nitrogen up to 10(20) cm(-3), and both photoluminescence and Raman characterization exhibit nitrogen related peaks. As-deposited layers have been characterized by Hall effect, and most exhibit n-type conductivity, with electron concentrations from 10(17) up to a few 10(19) cm(-3). Unstable p-type behavior is sometimes observed on low quality layers grown using a very low R-VI/II ratio. Ex situ annealing experiments in oxygen atmosphere show different tendencies depending on the growth conditions and can lead to a strong decrease in the electron concentration by three orders of magnitude. These results are discussed in relation to the structural and optical characterizations.