Nov.  22, 2018  94  US 2018/0335696 Al  C$_{1 }$-C$_{12 }$ linking group contmmng an ester moiety and/or  lactone ring, Y 2  is a single bond or ester group, R$^{11 }$and R 12  are each independently an acid labile group, R $^{13 }$is halogen,  trifluoromethyl, cyano, C$_{1 }$-C$_{6 }$ straight, branched or cyclic  alkyl or alkoxy group, or C$_{2}$-C$_{7 }$ straight, branched or cyclic  acyl, acyloxy or alkoxycarbonyl group, R$^{14 }$is a single bond  or C$_{1 }$-C$_{6 }$ straight or branched alkylene group in which at  least one carbon atom may be substituted by an ether or ester  moiety, p is 1 or 2, and q is an integer of O to 4.  5.  The resist composition of claim  4,  further comprising  a dissolution inhibitor, the resist composition being a chemi› cally amplified positive tone resist composition.  branched or cyclic alkoxycarbonyl group, mis an integer of  1 to 4, and n is an integer of Oto 3.  3.  The resist composition of claim  1,  further comprising  an organic solvent.  4.  The resist composition of claim  1,  wherein the polymer  further comprises recurring units having the formula (bl) or  (b2):  6.  The resist composition of claim  1  wherein the polymer  is free of an acid labile group.  7.  The resist composition of claim  6,  further comprising  a crosslinker, the resist composition being a chemically  amplified negative tone resist composition.  8.  The resist composition of claim  1,  further comprising  a surfactant.  9.  A process for forming a pattern comprising the steps of  applying the resist composition of claim  1  onto a substrate,  baking to form a resist film, exposing the resist film to  high-energy radiation, and developing the exposed film in a  developer.  10.  The process of claim  9  wherein the high-energy  radiation is ArF excimer laser radiation of wavelength 193  nm or KrF excimer laser radiation of wavelength 248 nm.  11.  The process of claim  9  wherein the high-energy  radiation is electron bemn or extreme ultraviolet radiation of  wavelength 3 to 15 nm.  *  *  *  *  *  wherein  RA  is independently hydrogen or methyl, Y 1  is a  single bond, phenylene group, naphthylene group, or a  (bl)  (b2) 