  We have observed an aggregation of carbon or carbon derivatives on platinum
and natively oxidized silicon surfaces during STM measurements in ultra-high
vacuum on solvent-cleaned samples previously structured by e-beam lithography.
We have imaged the aggregated layer with scanning tunneling microscopy (STM) as
well as scanning electron microscopy (SEM). The amount of the aggregated
material increases with the number of STM scans and with the tunneling voltage.
Film thicknesses of up to 10 nm with five successive STM measurements have been
obtained.

Mesoscale and Nanoscale Physics;Materials Science