Role of scanning probe microscopes in the development of nanoelectric devices

The last six years have witnessed the rapid development of several techniques of nanometer and atomic scale material manipulation using scanning probe microscopes (SPM). A stage has now been reached where we can explore the possibilities of using this technology to make practical nanometer-scale electronic devices. We feel that there are two key elements to this issue-(i) a nano-device must be physically accessible to the macro-world; and (ii) a nano-device that exploits quantum phenomena should be electronically accessible and should operate under ambient conditions. In view of this, the first part of the paper is devoted to discussing the different SPM lithographic techniques that will form the physical interface between the micrometer and the nanometer scales. The second part critically explores the possibilities of using SPM for developing molecular electronic devices, arguing that their small size may allow single-electron effects to be exploited at ambient temperatures.