NiO films were grown on Si (100) by atomic layer deposition using (,) or [,] and ozone in the temperature range. The growth temperature dependence of structure, electronic density, and impurity levels for the prepared NiO films was studied using X-ray reflectivity, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, time of flight–secondary ion mass spectroscopy (ToF-SIMS), and transmission electron microscopy. The behavior of films deposited using and is compared and discussed. NiO films with good stoichiometry and low amounts of contaminants are obtained at a growth temperature of or above. At a fixed, the growth rate for NiO films deposited using is higher than the one of films deposited using. Furthermore, the growth rate for NiO deposited using at is and decreases substantially in films deposited at higher temperatures. The electronic density of NiO films deposited at is close to the one of …