  We report low temperature current-voltage measurements on n-type InN films
grown by molecular beam epitaxy. The zero-resistance state with a large
critical current around 1 mA has been observed at 0.3 K. Under in-plane field
configuration, the zero-resistance state shows a large anisotropy in critical
current for B parallel and perpendicular to applied current. The ratio of
critical current between B parallel and perpendicular to the applied current
can be up to 2.5, when B = 0.15T. The anisotropy is explained by the vortex
flow in the context of type II superconductivity. We have thus established an
important aspect of the phenomenology of superconductivity in an otherwise
typical narrow gap semiconductor.
