We have used a 20 keV Ga focused ion beam to pattern superconducting submicrometer bridge structures in thin films of Ba2YCu3O7material by physical sputtering. The technique can produce structures down to 0.5 &mgr;m or less in epitaxial films with no degradation in superconducting transition temperature (Tc) or critical current density (Jc). Photolithography was used to define a coarse pattern of 20‐&mgr;m‐wide and 50‐&mgr;m‐long strips, each wired for four‐terminal resistance measurements. Submicrometer constrictions were then milled by the focused ion beam to form weak‐link junctions with roughly 0.3 &mgr;m separating the superconducting banks. We have demonstrated that focused ion beam micromachining is capable of producing submicrometer‐sized superconducting structures.