A semiconductor device including a damascene superconducting interconnect, formed of a Ba--Cu--Ca--O superconducting material. A method of forming a superconducting damascene interconnect structure, and the structure made thereby, the method including forming a cavity in an interlevel dielectric; forming a barrier layer in the cavity; forming a seed layer in the cavity over the barrier layer; forming a Cu--Ba alloy layer; filling the cavity by depositing a Cu--Ca--O film; and annealing in oxygen flow to form a Ba--Cu--Ca--O superconductor on the barrier layer. In an alternate embodiment, no barrier layer is formed.