Thermoelectric properties of amorphous ZnO<i>x</i>N<i>y</i> thin films at room temperature

Abstract

The thermoelectric properties of amorphous ZnOxNy (a-ZnON) thin films were investigated at room temperature. The a-ZnON thin films fabricated by nitrogen-plasma assisted pulsed laser deposition exhibited good n-type thermoelectric properties, of a power factor of up to 204 μW m−1 K−2. This value was more than twice higher than the value reported for known amorphous oxide semiconductors, which are candidate materials for IoT energy harvesting applications, having low processing temperatures suitable for plastic flexible substrates. The thermal conductivity of the a-ZnON thin films was in the range from 1.1 ± 0.2 to 1.4 ± 0.2 W m−1 K−1, which was low in comparison to amorphous oxide semiconductors. Due to the better properties, the thermoelectric figure of merit reached 0.042 at room temperature, which is significantly higher than that of known amorphous oxide semiconductors.