Positive electron beam resists of ortho chloro substituted phenol or cresol condensed with formaldehyde
AssigneeInternational Business Machines Corporation
InventorsJames Economy, Roy J. Gritter, Hiroyuki Hiraoka
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Abstract
The sensitivity of a positive working electron beam resist is increased by using as the resist material a resin which is a condensation product of formaldehyde with a phenol or a cresol having a chloro substituent ortho to the hydroxyl group on its aromatic ring.
Claims3
In a process for forming a positive electron beam resist by the steps of imagewise exposing a resin sensitized by a naphthoquinone diazide to electron beam irradiation, and selectively removing the exposed portion of the resin by treating it with a solvent, the improvement characterized in that the resin is a condensation product of formaldehyde with a phenol or a cresol having a chloro substituent ortho to the hydroxyl group on its aromatic ring.
Dependencies are inferred from the claim text.