Superconducting and normal properties of the set of Mo/Si superlattices with variable Si layer thickness

We report the results of the superconducting and kinetic parameter measurem ents (transition temperature T-c, parallel and perpendicular critical field s H-c2, resistivity in the normal state) on a set of Mo/Si superconducting superlattices with a constant metal layer thickness d(Mo)=22 Angstrom and v ariable semiconducting one d(Si)(14-44 Angstrom). Our data show a monotonic dependence of all measured parameters on d(Si). It is found that the Josep hson interlayer coupling energy depends exponentially on the spacer thickne ss. The data obtained allowed us to determine the characteristic electron t unneling length for amorphous silicon with high precision. It is equal to 3 .9 Angstrom. Enhancement of interlayer coupling leads to the Mo. Si multila yer transition temperature increasing, in agreement with Horovitz theory an d with the experimental data on high-T-c materials. (C) 1999 American Insti tute of Physics.