Nanometer-scale hole formation on graphite using a scanning tunneling microscope

Abstract
We present a reproducible technique for forming holes on a graphite surface with a scanning tunneling microscope. The holes have an average diameter of 40 Å (20 Å minimum) with an average resolvable spacing of 60 Å. Holes are produced by applying a short voltage pulse (3–8 V, 10–100 μs) across the tunneling gap which removes one or more layers of graphite in a small region directly below the tip. Arrays of hundreds of holes have been formed with yields as high as 99.6%. The writing process has a higher success rate in air or in the presence of water vapor. This suggests that the physical mechanism is a chemical process.