Thermoelectric properties of Bi0.5Sb1.5Te3 thin films grown by pulsed laser deposition

We report on the pulsed laser deposition of p-type Bi0.5Sb1.5Te3 thin films onto fused silica substrates by ablation of dense targets of Bi0.5Sb1.5Te3 with an excess of 1 wt% Te. We investigated the effect of film thickness, substrate temperature and post-annealing duration on the thermoelectric properties of the films. Our results show that the best power factor (2780 μW/K2m at 300 K) is obtained for films grown at room temperature and then post-annealed in vacuum at 300 °C for 16 h. This is among the highest power factor values reported for Bi0.5Sb1.5Te3 films grown on fused silica substrates.