Liquid nitrogen CMOS system study

In a liquid-nitrogen CMOS (LNCMOS) study, all major technical areas of interest were investigated including: device design and modeling, circuit design, process design, packaging, reliability, testing, refrigeration systems, system applications, and performance. In each of these areas, physical hardware was evaluated to determine the actual advantages. Three IBM CMOS technologies were evaluated to determine relative system performance improvements: 1.0- mu m n-well CMOS, n/sup +/ polysilicon, 5-V operation; 0.5- mu m n-well CMOS, n/sup +/ polysilicon with silicide on polysilicon and diffusions (salicide), 3.3-V operation; and 0.5- mu m n-well CMOS (LNCMOS), n/sup +/ silicide on nFET and p/sup +/ silicide on pFET, threshold voltage implant optimization, 2.5-V operation. These three CMOS technologies are closely related to each other by scaling and the LNCMOS process is an optimization of the 0.5- mu m CMOS process. It is concluded that LNCMOS is a viable system technology for military and commercial systems.<>