Sub-100 nm lithography using KrF exposure with multiple development method

Describes a novel resist process technique, using a chemically amplified resist with a multiple development method for improving resolution of photolithography. By means of this technique, a grating resist pattern whose frequency is more than a cutoff frequency of the optics (vc=1/Pc=2NA//spl lambda/) can be delineated using a conventional exposure system. This process uses a resist that allows either positive or negative imaging depending on the selection of a developer solvent.