Superconducting microstrip resonator on YSZ buffered silicon

Abstract

For the purpose of comparison we have fabricated identical microstrip gap-coupled meanderline half-wave resonators using both 500 nm thick aluminum and 500 nm thick YBa 2Cu 3O 7 high temperature superconductor films on 50 Ω cm (1 0 0) silicon buffered with a 50 nm film of yittria stabilized zirconia. The YBa 2Cu 3O 7 films were crack-free and exhibited a zero resistance temperature of 82 K. Measured Q-values at 15 K for this resonator were 560, in good agreement with the literature value of 0.002 for the tan δ for this type of silicon at these temperatures. The aluminum structures did not exhibit any resonance whatsoever. Clearly there is a significant advantage in using YBa 2Cu 3O 7 films at low temperatures. Fabrication, measurement and materials characterization are presented and the implications of the result are discussed.