Polymer, resist composition and patterning process

摘要

A polymer comprising recurring units of formula (1) and having a Mw of 1,000-500,000 is provided. R<1> is H, methyl or CH2CO2R<3>, R<2> is H, methyl or CO2R<3>, R<3> is alkyl, R<4> is H, alkyl, alkoxyalkyl or acyl, R<5> and R<15> are acid labile groups, and at least one of R<6> to R<9> is a carboxyl or hydroxyl-containing monovalent hydrocarbon group, and the reminders are H or alkyl, at least one of R<10> to R<13> is a monovalent hydrocarbon group containing a -CO2- partial structure, and the reminders are H or alkyl, R<14> is a polycyclic hydrocarbon group or polycyclic hydrocarbon-containing alkyl group, Z is a trivalent hydrocarbon group, k = 0 or 1, x is > 0, a, b, c and d are≥0, satisfying x+a+b+c+d = 1. A resist composition comprising the polymer has significantly improved sensitivity, resolution and etching resistance and is very useful in microfabrication.