MICROWAVE COMPATIBLE YBA2CU3O7-DELTA FILMS ON (001)MGF2 SUBSTRATES

High quality YBa2Cu3O7-delta (YBCO) films have been epitaxially grown on low dielectric constant, low loss tangent (001)MgF2 substrates using a double buffer layer scheme. The YBCO films are (001) oriented, exhibit T(c)'s of 88-89 K with transition widths less-than-or-equal-to 0.5 K and J(c)'s of 4 x 10(6) A/cm2 at 77 K in zero field. Dielectric resonator experiments indicate unloaded Q values in excess of 30 000 at 77 K and 24 GHz in the unpatterned films. Films patterned into meanderline resonators and operating at 10 GHz, 79 K, exhibit surface resistance (R(s))<1 OMEGA suggesting near-future realization of low loss superconducting components in the millimeter-wave region.