Electrical conduction in discontinuous metal films

Abstract

Electrical conduction in ultra-thin metal films is examined and the part played by an anomalous quantum mechanical tunnelling process is investigated. The process varies greatly with temperature, because the discrete metal particles forming the film are very small. The work required to remove a charge from such a particle being an inverse function of the particle size. The nature of the conduction path between the metal particles is considered, and it is shown that conduction occurs through the substrate supporting the film. Experimental results for gold, platinum end chromium films on soda and alumino-borosilicate glasses are analysed in terms of a proposed model. The consistency of the values of the barrier heights between the metal particles and the glass substrate, supports the quantum mechanical tunnelling model.