Thermoelectric properties of n-type Bi2Te2.7Se0.3 and p-type Bi0.5Sb1.5Te3 thin films deposited by direct current magnetron sputtering

n-type and p-type thermoelectric thin films have been deposited by direct current magnetron sputtering from n-type Bi2Te2.7Se0.3 and p-type Bi0.5Sb1.5Te3 targets on glass and Al2O3 substrates. X-ray diffraction and energy dispersive spectrometry combined with electrical measurements such as Seebeck coefficient and electrical resistivity were used for the thermoelectric thin films characterization. It was found that the composition of the sputtered thin films was close to the sputtering target stoichiometry for the tested deposition conditions and that the thin film composition did not seem to be the determinant parameter for the thermoelectrical properties. Indeed, the chamber pressure and plasma power have a greater influence on the thermoelectrical performances of the films. Annealing in Ar atmosphere (250 °C for n-type and 300 °C for p-type films) enhanced the film crystallization and yield power factors higher than 1 mW/K2 m.