Method to reduce plasma etch fluting

摘要

The present invention is directed to a method and process to reduce plasma etch fluting during etching of a pattern on a semiconductor substrate by modifying the resist profile. The present invention forms a resist structure profile having an overhang or undercut, which is not in contact with the surface of the substrate. The overhang results in a shadowed region on the substrate from the primary etch direction adjacent to the base of the resist structure.Since the overhang is not in direct contact with the substrate surface, the resist pattern does not transfer into the surface of the substrate during etching and fluting is reduced or eliminated.