Preparation and thermoelectric power properties of highly doped p-type Sb2Te3 thin films

Abstract In this study, we provide facile procedures for the growth of p-type Bi-doped Sb2Te3 thin films on ceramic substrates using vacuum thermal evaporation technique. Crystal structure and surface morphology of the prepared films were probed via powder X-ray diffraction (PXRD) and scanning electron microscope (SEM). The thermoelectric power properties were investigated, in terms of electrical conductivity and Seebeck coefficient measurements, over the temperature range from room temperature up to 473 K. The electrical conductivity behavior showed notable transition from metallic behavior to semiconducting as a function of temperature. In addition, Seebeck coefficient measurements confirmed this transition and supported the behavior of the electrical conductivity. Importantly, power factor was estimated based on both the electrical conductivity and Seebeck coefficient values. A maximum value of 227.6 μW/m.K2 was obtained for the Sb1.85Bi0.15Te3 thin film sample at 428 K.