Positioning single atoms with a scanning tunnelling microscope

Abstract

SINCE its invention in the early 1980s by Binnig and Rohrer^1,2, the scanning tunnelling microscope (STM) has provided images of surfaces and adsorbed atoms and molecules with unprecedented resolution. The STM has also been used to modify surfaces, for example by locally pinning molecules to a surface³ and by transfer of an atom from the STM tip to the surface⁴. Here we report the use of the STM at low temperatures (4 K) to position individual xenon atoms on a single-crystal nickel surface with atomic pre-cision. This capacity has allowed us to fabricate rudimentary structures of our own design, atom by atom. The processes we describe are in principle applicable to molecules also. In view of the device-like characteristics reported for single atoms on surfaces^5,6, the possibilities for perhaps the ultimate in device miniaturization are evident.