Absolute Seebeck coefficient of thin platinum films

Abstract

The influence of size effects on the thermoelectric properties of thin platinum films is investigated and compared to the bulk. Structural properties, like the film thickness and the grain size, are varied. We correlate the electron mean free path with the temperature dependence of the electrical conductivity and the absolute Seebeck coefficient S Pt of platinum. A measurement platform was developed as a standardized method to determine S Pt and show that S Pt, film is reduced compared to S Pt, bulk. Boundary and surface scattering reduce the thermodiffusion and the phonon drag contribution to S Pt, film by nearly the same factor. We discuss in detail on behalf of a model, which describes the temperature dependence of the absolute Seebeck coefficient, the influence of size effects of electron-phonon and phonon-phonon interaction on S Pt.