Superconductor Technologies Inc, Santa Barbara, California claims to have constructed the world’s first superconducting multichip module as part of a contract for the US Defense Advanced Research Projects Agency.The module uses 10-micron wide superconducting lines as the interconnect between the CMOS circuitry, and consists of nine CMOS digital inverters connected to form a ring oscillator and a counter. The hybrid circuit was tested at minus 196oC, a temperature achievable using liquid Nitrogen cooling and was built using the company’s Thallium thin film fabrication and metalisation processes. The Thallium superconductor was discovered at the University of Arkansas in 1988 and is a ceramic of Thallium, Barium, Calcium, Copper and Oxygen. The goal of the project, which is being led by E-Systems Inc’s Melpar Division in Falls Church, Virginia, is to develop, produce and market multichip modules with up to 1,000 times the performance of conventional modules by using superconductors on diamond substrate.
