Combined effect of oxygen deficient point defects and Ni doping in radio frequency magnetron sputtering deposited ZnO thin films

• ZnO thin films prepared by radio frequency magnetron sputtering technique
• Synthesis process was stimulated to introduce Schottky-type point defects.
• Point defects and external doping of Ni made ZnO thin films more functional.
• Point defect induced high electrical conductivity in ZnO thin film.
• Significant shift in optical bandgap observed in ZnO with Ni doping concentrations

Ni doped ZnO thin films with oxygen deficiency have been synthesized on glass substrates by radio frequency magnetron sputtering technique using argon plasma. The combined effect of point defects generated due to oxygen vacancies and Ni doping on the optical and electrical properties of ZnO thin films has been studied in this work. Ni doping concentrations were varied and the structural, optical and electrical properties of the films were studied as a function of doping concentrations. The films were characterized with X-ray diffractometer, UV–Vis–NIR spectrophotometer, X-ray photoelectron spectroscopy, atomic force microscopy and electrical conductivity measurements. Oxygen deficient point defects (Schottky defects) made the ZnO thin film highly conducting while incorporation of Ni dopant made it more functional regarding their electrical and optical properties. The films were found to have tunable electrical conductivity with Ni doping concentrations.