Topcoats for use in immersion lithography

摘要

A method of forming a top coat layer and a topcoat material for use in immersion lithography. A topcoat layer is formed on a photoresist layer from an aqueous solution that is immiscible with the photoresist layer. The topcoat layer is then rendered insoluble in neutral water but remains soluble in aqueous-base developer solutions so the photoresist may be exposed in a immersion lithographic system using water as the immersion fluid, but is removed during photoresist development. The topcoat materials are suitable for use with positive, negative, dual tone and chemically amplified (CA) photoresist.