Size effect of the resistivity of thin epitaxial gold films

Abstract

The temperature dependence of the electrical resistivity of thin, epitaxial, and flat (111)-oriented gold films with thickness between 2 and $50\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ is investigated. The quality of these Au films is superior to epitaxial Au films grown on mica, therefore the investigation of well-defined thin films was possible. The experiments are analyzed within the frame of classical size-effect theories of the resistivity. It turns out that for thin films, the characteristic Debye temperature is strongly decreased as compared to the bulk value. In contrast to the more physically motivated approach of Soffer, the original model of Fuchs-Sondheimer describes the experimental data in a physically consistent way.