Mo films and Mo/Si superlattices: comparison of superconducting and kinetic parameters

The results are given of the investigations of the superconducting and kinetic parameter dependences on the metal layer thickness for Mo films and Mo/Si multilayers in the same thickness range. It is found that quantum size oscillations observed on Mo/Si multilayers are absent on the single Mo films. It follows from the comparison of the data obtained for films and superlattices that oscillation effects characteristic for multilayered samples cannot be explained in terms of usual quantum size effect. This effect is absent in the individual Mo films because of strong disordering leading to the mean free paths of electrons less than the film thickness. The size oscillations associated with the space quantization of the electron spectrum should not be observed on Mo/Si multilayers too, because Mo layers in superlattices are also strongly disordered. Most likely, one may explain the oscillation effects on superlattices if taking into account the tunnel properties of semiconducting barriers separating metal layers