RESIST POLYMER CONTAINING NO HIGH POLYMER AND PREPARATION METHOD THEREOF TO REDUCE DIFFERENCE BETWEEN LOTS, REACTORS AND SCALES AND TO IMPROVE SOLUBILITY AND STORAGE STABILITY

摘要

PURPOSE: A resist polymer and its preparation method are provided, to reduce the difference between lots, reactors and scales by reducing the effect of temperature increasing velocity compared with dropping polymerization and to improve solubility and to suppress the growth of insoluble impurities during storage by containing no high polymer. CONSTITUTION: The resist polymer comprises at least a repeating unit having a structure which is degraded by an acid to become soluble to an alkali developer and a repeating unit having a polar group which increases the adhesion to a substrate, wherein the percentage of the peak area of high molecular weight part having a molecular weight of 100,000 or more is 0.1 % or less in the molecular weight distribution measured by gel permeation chromatography. The resist polymer is prepared by supplying a solution containing a polymerizable monomer and a solution containing a polymerization initiator into a polymerization system continuously or intermittently for radical polymerization with storing the solution containing a polymerizable monomer and the solution containing a polymerization initiator in independent tanks, respectively.