Stacked 3-D Fin-CMOS technology

A stacked three-dimensional Fin-CMOS (SF-CMOS) technology has been proposed and implemented. The technology is based on a double-layer SOI wafer formed by performing two oxygen implants to form two single-crystal silicon films with isolation layer in between. The proposed approach achieves a 50\% area reduction and significant shortening of wiring distance between the active devices when compared with existing planar CMOS technology. The SF-CMOS technology also inherits the scalability and two-dimensional processing compatibility of the FinFET architecture

A three-dimensional stacked Fin-CMOS technology for high-density ULSI circuits

In this paper, a three-dimensional CMOS technology is proposed and implemented using stacked Fin-CMOS (SF-CMOS) architecture. The technology is based on a double layer silicon-on-insulator wafer formed by two oxygen implants to create two single-crystal silicon films with an oxide isolation layer in between. The proposed approach achieves a 50\% area reduction and significant shortening of the wiring distance between active devices through vertical connection when compared with conventional planar CMOS technology. The SF-CMOS technology also inherits the scalability and two-dimensional processing compatibility of the FinFET structure. SF-CMOS devices and simple circuits were fabricated and characterized

Comparison of 61 Sequenced Escherichia coli Genomes

Escherichia coli is an important component of the biosphere and is an ideal model for studies of processes involved in bacterial genome evolution. Sixty-one publically available E. coli and Shigella spp. sequenced genomes are compared, using basic methods to produce phylogenetic and proteomics trees, and to identify the pan- and core genomes of this set of sequenced strains. A hierarchical clustering of variable genes allowed clear separation of the strains into clusters, including known pathotypes; clinically relevant serotypes can also be resolved in this way. In contrast, when in silico MLST was performed, many of the various strains appear jumbled and less well resolved. The predicted pan-genome comprises 15,741 gene families, and only 993 (6%) of the families are represented in every genome, comprising the core genome. The variable or ‘accessory’ genes thus make up more than 90% of the pan-genome and about 80% of a typical genome; some of these variable genes tend to be co-localized on genomic islands. The diversity within the species E. coli, and the overlap in gene content between this and related species, suggests a continuum rather than sharp species borders in this group of Enterobacteriaceae