Properties of Pd/Au thin film layered structures

Abstract

We have synthesized, by rf sputtering, Pd/Au layered structures with periodicities (Pd+Au layers) that vary from 15–95 Å. The films have been characterized by x-ray diffraction. The individual metal layers have (111) orientation perpendicular to the plane of the film. We accurately model the positions and intensities of x-ray lines by a one-dimensional diffraction grating of Pd and Au layers and relate the observed x-ray line widths to loss of long-range layer coherence induced by dislocations at Pd–Au interfaces. We also find that the in-plane electrical resistivity of the films varies inversely, and the temperature coefficient of resistance directly with the layer period. We account for both of these trends by considering scattering of electrons from the metal interfaces, using a modified Fuchs theory.