Superconductive microelectronics

Major progress and breakthroughs had occurred during the last decade in the field of Superconductive Electronics. This is related both to the discovery of high temperature oxide superconductors shortly later applied to microwave passive devices and simple SQUID magnetometers, but the biggest progress has been made, during the same period, on the achievement of large scale integrated (LSI) circuits using conventional superconductive multilayers. Circuits made of niobium tunnel junctions are working at 4.2 K in a liquid helium cooling system, those made of niobium nitride (NbN) junctions, working at 9K, in double stage refrigerators are even more attractive. Applications of such superconductive circuits are covering various fields such as high speed electronics (BW similar to 50 GHz), submillimeter "SIS" heterodyne receivers, digital devices made of RSFQ logic gates (ADC/DAC, autocorrelators, flash digitizers, switching circuit networks, arithmetic units for future Petaflops-scale computers,...), devices for Metrology and NDE, functional and topographic brain investigation using multichannel SQUIDs systems (MEG),... Superconductive Electronics do not require critical design rules or very narrow linewidth in the circuit fabrication but would surely benefit in the future in the development of silicon microelectronics, VLSI circuits Foundry services and innovative microchip or Microsystems designs.