  We studied the transport properties of meso-junctions of semiconducting (Sm)
highly doped Si with different superconductors (Sc) through point contact
Andreev reflection (PCAR) spectroscopy. Spectra of low transparency point
contacts between Si and In showed an enhancement in the superconducting energy
gap of In. This was due to the effect of an additional gap arising from the
Schottky barrier at the Sm-Sc interface. For higher transparency Si-Nb and
Si-Pb point contacts, no gap enhancement was observed though there were weak
sub gap features. These were due to proximity induced interface
superconductivity known to occur for Sm-Sc junctions of high transparency.
