Scanning tunnelling engineering

The great potential for building molecular scale machines and other structures was first noted by Richard Feynman (1960). He also proposed the development of tools to construct nanoscale mechanisms and devices. The range of technology that he proposed is now called nanotechnology, a term coined by Taniguchi (1974). Emergence of STM and related technology should greatly facilitate the development of nanotechnology in the decades to come. Franks' (1987b) review of nanotechnology notes the tremendous potential of STM‐derived tools for what he terms ‘scanning tunneling engineering’. However, STM technology can also augment the ‘bottom up’ approaches to nanotechnology, exemplified for example by Forrest Carter's (1979, 1980, 1982, 1983) proposals for building molecular electronic devices (nanocomputers) using synthetic ‘modular chemistry’ and related techniques of supramolecular chemistry (Kuhn & Mobius, 1971; Kuhn, 1983; Lehn, 1980, 1988). A multi‐tip STM system integrated with an optical microscope was proposed in 1986 as a ‘nanotechnology workstation’ suitable for scanning tunnelling engineering (Schneiker & Hameroff, 1988). In this paper, we describe an overview of scanning tunnelling engineering, present concepts for nanosensors and nanoswitches, and discuss design considerations for dual tip STM. Finally, we repeat an announcement of a series of ‘Feynman’ prizes for miniature STM. 1988 Blackwell Science Ltd