Cryogenic operation of CMOS-based microsystems and computers

The role of a cryogenic environment in improving the operational characteristics of CMOS-based digital circuits and systems has been well documented. Furthermore, it is expected that the recent discoveries of high temperature ceramic superconductors, while important in themselves, can also play an important role in defining the future directions of high speed/high density/high performance, large electronic systems, particularly at liquid nitrogen temperatures (77 K). In the paper, the performance characteristics of large microelectronic systems such as microprocessors, microsystems and supercomputers are discussed, particularly their performance enhancements at 77 K. The impact and promise of the new ceramic superconductors as high speed interconnections in large microelectronic systems will also be described, and the salient features of conceptual hybrid superconductor/semiconductor systems, operating at either 77 K or at both 77 K and 300 K, will be discussed.