S. Afonso et al., Y1BA2CU3O7-X MULTILAYER STRUCTURES WITH A THICK SIO2 INTERLAYER FOR MULTICHIP MODULES, Journal of materials research, 12(11), 1997, pp. 2947-2951
For high temperature superconducting multichip modules and other relat
ed electronic applications, it is necessary to be able to fabricate se
veral Y1Ba2CU3O7-x (YBCO) layers separated by thick low dielectric con
stant dielectric layers. In this work, we report the successful fabric
ation of YBCO/YSZ/Si-O2 (1-2 mu m)/YSZ/YBCO multilayer structures on s
ingle crystal yttria stabilized zirconia (YSZ) substrates. In contrast
to previously reported work, the top YBCO layer did not show any crac
king. This is due to a technique that allows for stress relief in the
SiO2 layer before the second YBCO layer is deposited. The top YBCO lay
er in our multilayer structure had T-c = 57 K and J(c) = 10(5) A/cm(2)
(at 77 K), whereas the bottom YBCO layer had T-c = 90 K and J(c) = 1.
2 x 10(6) A/cm(2) (at 77 K). We also showed that the quality of the bo
ttom YBCO layer was preserved during the fabrication of the multilayer
due to the annealing process during which O-2 diffused into the YBCO,
replacing the O-2 lost during the deposition of the top YBCO layer.