Annealing-temperature effects on the properties of ZnO thin films and Pd/ZnO Schottky contacts grown on n-Si (1 0 0) substrates by vacuum deposition method

• Fabrication of ZnO thin films on n-Si substrates by thermal evaporation technique.
• Annealing temperature effects in Ar gas on the properties of ZnO thin films.
• Structural, optical and electrical properties of the films in 450–650 °C.
• Good gas sensing properties observed at 450 °C annealing temperature.
• Effects of annealing temperature on Pd/ZnO film/n-Si Schottky diodes.

The effects of annealing temperature on the properties of ZnO thin films and Pd/ZnO thin film Schottky contacts grown on the n-silicon (n-Si) substrates by vacuum evaporation technique have been reported for the first time in this paper. The as-grown ZnO thin films were annealed in the Argon gas atmosphere for a same duration of 20 min at 450 °C, 550 °C and 650 °C temperatures. The surface morphology of the films analyzed by the scanning electron microscopy and X-ray diffraction spectroscopy are observed to be modified with annealing temperature. The photoluminescence and resistivity measurements were carried out to report the effects of annealing temperature on the optical and electrical properties of the vacuum deposited ZnO thin films. The Pd Schottky contacts grown on the annealed ZnO thin films at 550 °C annealing temperature is observed to have the superior electrical characteristics over the Schottky contacts on ZnO films annealed at 450 °C and 650 °C temperatures.