Method for fabricating nanoscale patterns on a surface

A novel method to fabricate nanoscale pits on Au(111)
surfaces in contact With aqueous solution is claimed. The
method uses in situ electrochemical scanning tunnelling
microscopy With independent electrochemical substrate and
tip potential control and very small bias voltages. This is
signi?cantly different from other documented methods,
Which mostly apply high and short voltage pulses. The most
important advantages of the present method are that the
dimensions and positions of the pits can be controlled With
high precision in aqueous environment so that nanopatterns
of the pits can be designed, and that the operations are
simple and require no instrumental accessories. Parameters,
Which control the pit formation and siZe, have been system
atically characterized and shoW that the primary controlling
parameter is the bias voltage. A mechanism based on local
surface reconstruction induced by electronic contact
betWeen tip and substrate is in keeping With the overall
patterns for pit formation. A range of potential applications
is proposed.