Effect of substrate bias voltage on the physical properties of dc reactive magnetron sputtered NiO thin films

▶ Nickel is reactively sputtered in the presence of oxygen by dc magnetron sputtering. ▶ The substrate bias voltage was highly influenced the physical properties of NiO films. ▶ The films were preferentially grown along (200) orientation at all bias voltages. ▶ The NiO films with good microstructure have grown at bias voltage of −75 V. ▶ The films grown at −75 V have high transparency and low electrical resistivity. Nickel oxide (NiO) thin films were prepared on glass substrates at various bias voltages using dc reactive magnetron sputtering technique. The influence of substrate bias voltage on structural, optical and electrical properties was systematically investigated using X-ray diffraction (XRD), SEM, EDS, spectrophotometer and Hall effect studies. The NiO films are crystalline with preferential growth along (2 0 0) plane. The NiO films exhibit optical transmittance of 55% and direct band gap of 3.78 eV at the substrate bias voltage of −75 V. The electrical resistivity decreases as substrate bias voltage increases from 0 to −75 V thereafter it was slightly increased.