SBIR-STTR Award

Stable, chemically inert, low resistivity contacts are required to take advantage of devices being in anufactured utilizing various high Tc oxide superconductors. The usual disruption in the oxidation state of the superconductor results in a significant degradation of the contact. Current contact technology utilizes noble metals such as Au, or Ag for the interconnections, but they are expensive and not compatible with AI or Cu interconnections found in most integrated systems. We have recently filed a Patent entitled, "Bi-layer low resistance contact to High Tc Oxide Superconductors." The technique described in this patent will be shown in this proposal to allow a general methodology to fabricate very stable, low resistance contacts to high temperature superconducting devices. During Phase I we will investigate the mechanical and thermal stability of bilayer contacts, initiate experiments to determine the optimum material for these systems, and extend the methodology to tri-layer systems. We will utilize XPS, Auger and electrical and thermal measurements to evaluate these new systems.

Stable, chemically inert, low resistivity contacts are required to take advantage of devices being developed utilizing high Te oxide superconductors. The usual disruption in the oxidation state obtained with non-optimum metallization to the superconductor results in a significant degradation of the contact. Current contact technology utilizes noble metals such as Ag,or Au for the interconnections found in most integrated systems. We have recently filed a patent entitled, "Bi-layer and Tri-layer low resistance contact to high Te oxide superconductors," and have demonstrated in Phase I that low resistance multilayer contacts can be fabricated in general purpose laboratory sputering equipment without utilizing ultra-high vacuum chambers. During Phase II we will develop bi-layer and tri-layer contact technology to reduce resistivities to 10(-8) to 10(-10) ohm-cm2 and to optimize the metal connections for eigher thin film interconnects, wirebonds, or solder attachment. A study of the optimum structures for long term electrical, thermal and mechanical stability will be made.

Keywords:
high temperature superconductors superconducting devices bi-layer contacts contact resistivity