Nanolithography of metal films using scanning force microscope patterned carbon masks

Recently, we have shown that small trenches in amorphous carbon films can b e produced by a field induced local oxidation with a voltage biased cantile ver tip in a scanning force microscope. The depth of the holes and the tren ches corresponds to the total thickness of the carbon film while the width was found to be as small as 30 nm. Amorphous carbon films as resist masks f or lithography show some advantageous properties, e.g., the stability again st halogen plasma etching, negligible chemical reactivity with most substra tes and the possibility of removing the mask by oxygen reactive ion etching . In this article; we demonstrate the transfer of the carbon patterns into metal films by argon ion beam etching. By this new method, we produced 10-n m-wide trenches in thin AuPd films. Furthermore, we made small gaps in narr ow AuPd lines which have been predefined by conventional e-beam lithography . In order to control and minimize the width of the gaps, the resistance of the conducting lines was controlled in situ during ion beam etching. (C) 1 998 American Vacuum Society. [S0734-211X(98)13506-0].