Electrical conduction and current noise in discontinuous platinum films

Conductivity and current-noise measurements in a wide temperature range on platinum films are reported. The experimental results are interpreted on the basis of a theory developed in a previous paper concerning the conductance mechanisms and the current-noise power spectrum of discontinuous metal films. The much lower current noise shown in these films with respect to the gold ones is interpreted, according to the theory, on the basis of much smaller island structure shown by platinum films. An anomalous behavior of the electrical conductivity and current noise experimentally observed at low temperatures on these films is explained in terms of the adsorption-desorption processes of residual vapor molecules.