Growth of superconducting Y-Ba-Cu-O films on spinel and garnet

Spinel and garnet single crystals of low dielectric constants and loss tangents have been investigated as possible substrate materials for the growth of the Y-Ba-Cu-O superconducting films. In addition to their desirable dielectric properties, these materials are chemically compatible with silicon and compound semiconductors and can be used as the interface materials for the integration of cuprate superconducting films with semiconducting devices. The Y-Ba-Cu-O films grown on (001) MgAl2O4 and (001) Y 3Al5O12 from a co-evaporation deposition with a subsequent wet anneal exhibit superconductivity with a transition temperature Tc(R=0) of 57 and 74 K, respectively, while strongly (001) textured YBa2Cu3O7-x films from the in situ laser deposition grown on (001) MgAl2O4 and (001) Y 3Al5O12 show superconducting transition temperatures Tc(R=0) of 77 and 87 K, respectively. Our work demonstrates that these two materials are viable substrates for the Y-Ba-Cu-O thin films in high frequency device applications.