Enhancement of the thermoelectric performance of (BiSb)2Te3 films by single target sputtering

In this study, (BiSb) 2Te3 films were deposited onto a glass substrate at 300 °C using radio frequency (RF) sputtering at various growth conditions. The effects of RF power, chamber gas pressure, and annealing temperature on the thermoelectric properties of the deposited films were investigated. An increase in the annealing temperature was found to enhance both the deposition rate and grain size. After optimizing the growth conditions and applying further annealing treatment, thin films grown at higher RF power exhibited higher electrical conductivity, attributable to an increase in carrier concentration. Additionally, films grown under 37.5 W RF power demonstrated an enhancement in the Seebeck coefficient, leading to a maximum power factor. The deposition chamber's base pressure was 10−6 mbar, and the optimal thermoelectric performance was achieved in the film grown under 0.04 mbar Ar+ partial pressure.