We have developed a non-ion-etching ion-beam-assisted-deposition (IBAD) process for fabricating high critical-temperature(Tc)grain boundary Josephson junctions through a photoresist liftoff mask. TheYBa2Cu3O7(YBCO) junctions fabricated through this process exhibited the resistively-shunted-junction (RSJ)-likeI–Vcharacteristics. The well-defined Shapiro steps have been seen on theI–Vcurves under microwave radiation. The magnetic modulation of critical current of a 4 &mgr;m width YBCO junction tallied with the prior simulated Fraunhofer diffraction pattern of a Josephson junction with a spatially homogeneous critical current density. The maximum peak-to-peak modulation voltage across the dc superconducting quantum interference device (SQUID) fabricated by using these junctions reached up to 32 &mgr;V at 77 K. The magnetic modulation of the SQUID exhibited periodic behavior with the observed modulation period of5.0×10−4 G.©1997 American Institute of Physics.