Polycrystalline NiOx thin films were deposited on quartz substrates by ion beam sputter deposition and oxidation annealing at high temperatures. X-ray diffraction (XRD) and scanning electron microscopy (SEM) morphologies indicate that the as-deposited nickel oxide thin films are flat amorphous nickel or oxides. However, they developed into semiconducting NiOx thin films during the oxidation annealing process. Four-point probe tests confirmed their sheet resistance and the resistance-temperature relationship. In addition, infrared (IR) measurements were also carried out in the visible spectrum range to study the optical properties of the as-deposited and annealed films. Apparently, the NiOx films obtained by the new method exihibit properties that are comparable to those of the films formed by other methods. The thin films have potential application as gas sensors.