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 SPt of platinum. We use a measurement platform as a standardized method to determine SPt and show that SPt,film is reduced compared to SPt,bulk. Boundary and surface scattering reduce the thermodiffusion and the phonon drag contribution to SPt,film by nearly the same factor. A detailed discussion and a model to describe the temperature dependence of the absolute Seebeck coefficient and the influence of size effects of electron-phonon and phonon-phonon interaction on SPt is given.
@article{arxiv.1903.12109,
title = {Absolute Seebeck coefficient of thin platinum films},
author = {M. Kockert and R. Mitdank and A. Zykov and S. Kowarik and S. F. Fischer},
journal= {arXiv preprint arXiv:1903.12109},
year = {2019}
}