Patent ID: 7572386

Claim:
A method of etching a thin film formed on a substrate and having a mask layer thereon, the method comprising: forming a pattern on the mask layer; treating said patterned mask layer with a pre-etching first ballistic electron beam formed by coupling negative polarity direct current (DC) power to an electrode in a plasma processing system in the absence of an atomic halogen specie in order to alter said patterned mask layer; and following said treating said patterned mask layer, etching said thin film in said plasma processing system in order to transfer a pattern of the mask to said thin film, said etching comprising: forming an etching plasma from an etching gas; forming a second ballistic electron beam to assist said etching plasma during said etching by coupling negative polarity direct current (DC) power to an electrode in said plasma processing system; and exposing said substrate to said etching plasma and said etching electron beam.