  We have patterned a hexagonal array of nano-scale holes into a series of
ultrathin, superconducting Bi/Sb films with transition temperatures 2.65 K
$<T_{co} < $5 K. These regular perforations give the films a phase-sensitive
periodic response to an applied magnetic field. By measuring this response in
their resistive transitions, $R(T)$, we are able to distinguish regimes in
which fluctuations of the amplitude, both the amplitude and phase, and the
phase of the superconducting order parameter dominate the transport. The
portion of $R(T)$ dominated by amplitude fluctuations is larger in lower
$T_{co}$ films and thus, grows with proximity to the superconductor to
insulator transition.
