Method for forming sublithographic features during the manufacture of a semiconductor device and a resulting in-process apparatus

Abstract

A method for forming a semiconductor device comprises forming a layer to be etched, then forming a hard mask layer over the layer to be etched. The hard mask is etched to form an opening defined by first and second cross-sectional sidewalls in the hard mask layer. In one embodiment, the opening in the hard mask layer is formed at the minimum limits allowable by optical lithography. A conformal spacer layer is formed over the hard mask layer and on the sidewalls of the hard mask, then spacer etched to form first and second cross-sectional spacers along the first and second sidewalls in the patterned hard mask layer. The hard mask and spacers are preferably formed from amorphous carbon. The layer to be etched is etched using the hard mask layer and the spacers as a pattern, then the hard mask layer and spacers are removed.