Improvement in thermoelectric properties of electrodeposited p-type Sb-Te thin films by performing thermal annealing and incorporating diffusion barrier layers

We investigated the thermoelectric properties of electrodeposited Sb-Te thin films using thermal annealing and incorporating diffusion barrier layer between the stainless steel substrate and the Sb-Te thin film. Molybdenum (Mo) and nickel (Ni) films were used as a diffusion barrier layer. Surface morphology was observed by scanning electron microscope, and crystallographic characteristic was examined by X-ray diffraction analysis. In-plane thermoelectric properties, in terms of the electrical conductivity, Seebeck coefficient and power factor, were measured at room temperature. It was found that Sb-Te thin film with Mo layer exhibited higher thermoelectric performance compared to that of Sb-Te thin film with no diffusion barrier layer. This is because the impurity atoms from the substrate and Mo layer itself did not diffuse so much into Sb-Te layer. On the other hand, Sb-Te thin film with Ni layer exhibited the lower thermoelectric properties owing to the diffusion of Ni atoms into the Sb-Te thin film. Therefore, incorporation of Mo layer is beneficial to improve the thermoelectric properties of Sb-Te thin films by thermal annealing.