The influence of annealing condition on the properties of the Co-Sb thermoelectric thin films prepared by ion beam sputtering

Co-Sb based thermoelectric materials has been identified as a new promising thermoelectric material because of its extremely high hole mobility, high thermoelectric power, and relatively low thermal conductivity due to complexity in the crystal structure. In this work, Co-Sb based thin films were prepared by ion beam sputtering technique and the annealing process had been used to optimize the thermoelectric properties of the thin films. The results indicate that the thin films annealed at vacuum chamber with the chamber pressure of 6.0x10(-4) Pa has worse thermoelectric properties than the thin films annealed at Ar atmosphere. The thin film with single CoSb3 phase which annealed at 400 degrees C at Ar atmosphere has a maximum power factor of 1.8 mWm(-1)K(-2) with the Seebeck coefficient of 50 mu V/K and the conductivity of 7x105 Sm-1. Also, the thermoelectric voltage of the thin film is stable through the testing temperature increases.