Effect of annealing temperature on the thermoelectric properties of ZnInO thin films grown by physical vapor deposition

Abstract

This research work has been demonstrated the growth of ZnInO thin films using thermal evaporation technique for thermoelectric power generation applications. The pure zinc powder and indium metal were evaporated on the multi-crystalline Si substrate using the vacuum tube furnace. Deposited thin films were annealed at various temperatures (500–700 °C) for 30 min in a programmable muffle furnace. XRD data concluded that the sample annealed at temperature 500 °C, has a weak structure of ZnO. But as we have increased the annealing temperature, indium atoms get thermal energy from the annealing process and reacted with ZnO molecule to form ZnInO composite. The vibrational and rotational modes of the samples were studied by the Raman spectroscopic analysis and morphology of annealed samples was verified by SEM. The Seebeck coefficient data suggested that the value of Seebeck coefficient varies between (140.9–182.2) μV/oC. The maximum value of the Seebeck coefficient was obtained for the sample annealed at 600 °C because the mobility of carriers is highest at that temperature. But the value of electrical conductivity and power factor for the sample annealed at 600 °C is minimum due to low carrier concentration. Because of these conclusions, it may be suggested that this material can be a potential choice soon for thermoelectric power generation applications.