Fabrication of n-type flexible Bi-Te-Se thermoelectric thin films through one-target magnetron sputtering

Low-cost, large-scale manufacturing of n-type flexible Bi-Te-Se thin films is vitally important for industrial application of the Bi2Te3-based thermoelectric materials. In this work, a facial one-target magnetron sputtering is employed to deposit Bi-Te-Se films at variable polyimide substrate temperatures. Subsequent annealing treatment is carried out to modulate the chemical compositions and microstructure. Consequently, benefiting from the synergetic optimization of the carrier concentration and mobility, the film deposited at 250 °C and annealed at 300 °C for 20 min reveals the highest power factor of 4.28 μW/cm K2 at 520 K, indicating comparable to or even better thermoelectric performance at high temperature than the related literature studies.