Deposition of high J_c YBa_2Cu_3O_(7-x) thin films by ultrasonic spray pyrolysis

摘要

We have demonstrated the viability of in situ ultrasonic spray pyrolysis (USP) for coating highly aligned YBa_2Cu_3O_(7-x) conductors some four years ago. In this work we demonstrate further improvement of these conductors by deposition of more highly concentrated precursor solution. Highly biaxially aligned, ～1 μm YBCO thick films were deposited in situ on single crystal (100) SrTiO_3 from nitrate precursor solutions. The typical growth rate was 0.3 μm/ min. J_c's were ～5 x 10~5 A/cm~(-2) at 77 K. At 40 K, magnetic measurements indicated good grain connectivity up to 7 T, although weaker connectivity was observed at 77 K.