Semiconductor devices and superconducting interconnections at 77 K: super-semi or semi-super

It is noted that, with semiconductor logic at 77 K providing an optimized, local active device behavior for logical operations, high-T_c superconducting transmission lines and Josephson tunnel junction drivers/receivers can provide a similarly optimized communications environment at 77 K. This combination of low-temperature active electronic devices and high-temperature superconducting interconnections is considered in the present work. The potential performance of transmission lines fabricated from thin-film, high-T_c superconductors is examined, and several practical issues degrading the potential performance of such interconnections are considered. Attention is given to issues connected with surface impedance, flux motion induced resistance, critical current density, thin film substrates, multilayer interconnections, high-quality surfaces, tunnel junction devices, large-area substrates, and reliability