An Overview of Nanoscale Devices and Circuits

Conventional lithography-based vlsi technology (mostly using CMOS) has been extremely successful in the deep-submicron region. As CMOS approaches its fundamental physical limits (as evidenced by ultra thin gate oxides, short channel effects, and so on), researchers have begun investigating new technologies at extremely small feature sizes (such as nanoscale below 45 nm) for manufacturing future electronic and computing systems. This article presents the basic principles of some emerging nanoscale technologies, with emphasis on novel devices and their implementation. We also highlight manufacturing issues and basic features in terms of performance, current state of development, and limitations to present a basic, yet comprehensive, overview of emerging technologies for nanoscale electronics. New devices proposed by researchers include carbon nanotubes, silicon nanowires, quantum-dot cellular automata (QCA), single-electron transistors, resonant tunneling diodes, and single-molecule devices.