We have been searching novel superconducting materials only at their surface regions using a homemade ultra high vacuum low
temperature scanning tunneling microscope. We found that scanning tunneling current-voltage curves on 5 Å thick Ag deposited
Ge(100) surfaces at 2.9 K are slight non-linear with an energy gap of a few meV. The temperature dependence of the non-linearity
suggests supercond activity on the surface alloys.