DEPOSITION THICK-FILM PATTERNS OF THE HIGH-T SUPERCONDUCTING Y-BA-CU-O AND BI-SR-CA-CU-O SYSTEMS ONC CERAMIC SUBSTRATES

Superconducting thick films of Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O on ZrO2:Y2O3 (YSZ), ZrO2:CaO and Al2O3 substrates were obtained by means of screen printing and direct painting. The microstructure and the chemical composition of the films and their reactivity with substrate material were characterized by optical and scanning electron microscopy, X-ray powder diffraction and electron probe microanalysis. For Y-Ba-Cu-O thick films with preferred orientation were obtained on ZrO2 doped with Y2O3 or CaO. The preferred c-axis orientation was caused by an interface reaction between YBa2CU3O7-x and YSZ or ZrO2:CaO. The resistivity measurements indicated that the Y-Ba-Cu-O films deposited on ceramic substrates and sintered at 1000 °C for about 6 min. gave a Tc of about 90 K. For Bi-Sr-Ca-Cu-O, thick films (Bi:Sr:Ca:Cu = 2:2:2:3) sintered at 890 °C for 10 min. to 1 h, the Tc-onset wa,s near 100 K. Planar and cylindrical test elements have been prepared for electrical measurements of conductivity and LC-distributed parameters. © 1990.