| 摘要 |
<P>PROBLEM TO BE SOLVED: To form an overlay film that is applied on a photoresist without inducing intermixing with the photoresist film, maintains stable coating without elution in a medium upon liquid immersion lithography, has a contact angle as large as ≥70° with respect to an immersion medium, having no degradation in a pattern shape when dry exposure, not liquid immersion lithography, is carried out, and can be easily dissolved in an alkali developing solution. <P>SOLUTION: An overlay film composition is used to form a pattern. The composition is a copolymer for a liquid immersion overlay, containing repeating units having a carboxyl group by 20 to 60 mol% in the whole repeating units and having a weight average molecular weight of 2,000 to 100,000 measured by gel permeation chromatography. The copolymer is obtained by copolymerizing a (meth)acrylate having a group including a fluorine atom in a side chain thereof. Further, the composition is obtained by copolymerizing a hydroxyl group-containing (meth)acrylate. <P>COPYRIGHT: (C)2011,JPO&INPIT |
