POLYMER MADE FROM MONOMER PREPARED BY BONDING CHOLIC ACID, DEOXYCHOLIC ACID, OR LITHOCHOLIC ACID DERIVATIVE TO NORBORNENE AND USE OF SAME

摘要

PROBLEM TO BE SOLVED: To obtain a substance which gives a phororesist being capable of transmitting an argon fluoride excimer laser wavelength of a specified value and transparent and having good dry etching resistance by homopolymerizing or copolymerizing a monomer prepared by bonding a cholic acid, deoxycholic acid, or lithocholic acid derivative of an aliphatic polycyclic structure to norbornene with maleic anhydride or the like. SOLUTION: The laser wavelength is 193 nm. The monomer is represented by the formula (wherein R1 and R2 are each H, methyl substituted on norbornene, OH, CH2OH, CO2CH3, to the like; R3 is (CH2)nO, CO(CH2)nO, or the like; n is 0-3; R4 and R5 are each H, OH, OCOCH3, or the like; and R6 is H, C(CH3)3, tetrahydropyranyl protective group, or the like). This is obtained by converting the acid group of cholic acid or the like into a protective group which leaves when treated with an acid and reacting the converted compound with a norbornene derivative such as 2-chlorocarbonyl-5-norbornene. This monomer is homopolymerized or copolymerized with maleic anhydride or the like to obtain the odjective substance.