  We present very low temperature Scanning Tunneling Microscopy and
Spectroscopy (STM/S) measurements in W-based amorphous superconducting
nanodeposits grown using a metal-organic precursor and focused-ion-beam. The
superconducting gap closely follows s-wave BCS theory, and STS images under
magnetic fields show a hexagonal vortex lattice whose orientation is related to
features observed in the topography through STM. Our results demonstrate that
the superconducting properties at the surface of these deposits are very
homogeneous, down to atomic scale. This, combined with the huge nanofabrication
possibilities of the focused-ion-beam technique, paves the way to use
focused-ion-beam to make superconducting circuitry of many different
geometries.
