Method for purifying resin for photolithography

Abstract

Provided is a method for purifying a resin for photolithography wherein, from an insufficiently purified resin (also referred to as “crude resin”), low molecular weight impurities such as an unreacted monomer and a polymerization initiator, which cause a development defect of a resist pattern or deterioration of the storage stability of the resin for photolithography can be removed more effectively. A method for purifying a resin for photolithography according to the present invention is characterized by comprising: an operation (a): an operation wherein a slurry in which a resin is dispersed in a solution containing a good solvent and a poor solvent is stirred; and then, an operation (b): an operation wherein, to said slurry, a poor solvent is added to lower the ratio of the good solvent to the poor solvent, and then, the resin is separated from the solution.

Dependencies are inferred from the claim text.