Smallest man-made object

Smallest man made object
By using field ion microscopy the tips of probes of scanning tunnelling microscopes have been shaped to end in a single atom-the last three layers constituting the world's smallest man-made pyramid, consisting of 7, 3 and 1 atoms. Since the announcement in January 1990 that D. M. Eigler and E. K. Schweizer of the IBM Almaden Research Center, San Jose, California, USA had used an STM to move and reposition single atoms of xenon on a nickel surface in order to spell out the initials `IBM', other laboratories around the world have used similar techniques on single atoms of other elements.