METHOD FOR PRODUCING COPOLYMER FOR SEMICONDUCTOR LITHOGRAPHY CONTAINING REDUCED AMOUNT OF METAL IMPURITIES, AND METHOD FOR PURIFYING POLYMERIZATION INITIATOR FOR PRODUCTION OF COPOLYMER

摘要

Disclosed are a method for producing a copolymer for semiconductor lithography containing less metal impurities, and a method for purifying a polymerization initiator for production of the copolymer. According to the present invention, the method for purifying a polymerization initiator to be used for production of a polymer comprises a filtering process for reducing the sodium content of the polymerization initiator solution to not more than 300 ppb with respect to the weight of the polymerization initiator by passing a solution of a polymerization initiator dissolved in an organic solvent through a filter having a nominal pore diameter of 1.0 m or smaller. In addition, the method for producing a copolymer for semiconductor lithography according to the present invention comprises a polymerization process for synthesizing the polymer for semiconductor lithography by a radical polymerization reaction in the presence of a polymerization initiator purified by the purification method of the present invention.;COPYRIGHT KIPO 2016