Investigation of sliding contact resistance of Ni-Cr/Au and Ni-Cr/Au-SiO 2 thin resistive films

Abstract

The contact resistance of Ni-Cr/Au and Ni-Cr/Au-SiO 2 thin resistive films with gold-plated metal sliding contact surface have been investigated. The thin resistive films were prepared by r.f. sputtering through a mechanical mask onto polished glass substrates. The interaction at the interface of thin resistive film and the contact slider determines the contact resistance and electrical noise of the system. Contact resistance is influenced by the composition of the thin film, sheet resistance, contact pressure, surface morphology, and diffusion process occuring during the annealing of thin films. The surfaces and depth profiles of thin resistive films were analysed by the Auger electron spectroscopy method. The lowest contact resistance was obtained with the Ni-Cr/Au-SiO 2 thin resistive film deposited onto polished glass substrates contacted with a wire brush made of Ni-Pd alloy.