Compositions and processes for immersion lithography
View Patent ↗New photoresist compositions are provided that are useful for immersion lithography. Preferred photoresist compositions of the invention comprises two or more distinct materials that can be substantially non-mixable with a resin component of the resist. Particularly preferred photoresists of the invention can exhibit reduced leaching of resist materials into an immersion fluid contacting the resist layer during immersion lithography processing.
1. A method for processing a photoresist composition, comprising:
(a) applying on a substrate a photoresist composition comprising:
(i) one or more resins that comprise photoacid-labile groups,
(ii) a photoactive component, and,
(iii) two or more resins that are non-mixable with the (i) one or more resins,
wherein:
the (iii) two or more non-mixable resins comprise (1) a first resin and (2) a second resin, and
the (1) first and (2) second resins differ by at least one polymer unit, and
the (ii) two or more non-mixable resins comprise aqueous base-solubilizing groups,
the (1) first and (2) second resins each comprise (i) flourine substitution, (ii) photoacid-labile groups, and (iii) base-solubilizing groups and
the (1) first and (2) second resins have greater hydrophobicity relative to the (i) one or more resins; and
(b) immersion exposing the photoresist layer to radiation activating for the photoresist composition.
2. The method of claim 1 wherein the (1) first and (2) second resins each has an Mw of 1500 to 20,000.