A multistep postannealing scheme has been developed for preparing nearly single phased,c‐axis oriented TlBa2Ca2Cu3Ox(Tl‐1223) superconducting thin films fabricated by the direct‐current‐sputtering process. Films obtained by the present process have shown, for the first time in this system, a critical current density (Jc) above 106A/cm2at 77 K with a zero‐resistance transition temperatureTc0≊110 K. The order of magnitude enhancement inJcis attributed to the improvement of film morphology which, in turn, removed most of the weak links encountered previously. ©1995 American Institute of Physics.