US 10,005,868 B2  80  79  -continued  It should be noted that the present invention is not limited  to the foregoing embodiment. The embodiment is just an  exemplification, and any examples that have substantially  the same feature and demonstrate the same functions and  effects as those in the technical concept described in claims  of the present invention are included in the technical scope  of the present invention.  What is claimed is:  1.  A resist composition comprising:  an organic solvent;  an acid generator, and  a base resin comprising a polymer compound having one  or more repeating units selected from repeating units al  to a5 shown by the following general formulae (2-1) to  (2-5), the polymer compound having a weight average  molecular weight ranging from 1,000 to 500,000,  (2-1)  (2-2)  (2-3)  (2-4)  0  (2-5)  ~  5  xs  OAO  Rs  wherein  R 1  and  R 3  to  R 5  represent a linear, branched, or  cyclic alkyl group having 1 to 4 carbon atoms, an alkenyl  group having 2 to 4 carbon atoms, or an alkynyl group  having 2 to 4 carbon atoms; R $^{2 }$represents a linear, branched,  or cyclic alkyl group having 1 to 4 carbon atoms, an alkenyl  group having 2 to 4 carbon atoms, or an alkynyl group  having 3 to 4 carbon atoms; R $^{6 }$represents a hydroxyl group  or an alkoxy group or an acyloxy group having 1 to 6 carbon  atoms; and "m" represents 1 or 2; X$^{1 }$to X$^{5 }$represent a single  bond or  -C(=0)---0-R 12 - where  R $^{12 }$represents a lin› ear, branched, or cyclic alky lene group having 1 to 10 carbon  atoms and optionally containing an ester group, an ether  group, or a lactone ring; R $^{7 }$to R $^{11 }$represent a hydrogen atom  or a methyl group; al to a5 satisfy 0sal <0.2, 0sa2<0.2,  0sa3<0.2,  0sa4<0.2, 0sa5<0.2, and 0<al+a2+a3+a4+  a5<0.2.  2.  The resist composition according to claim  1,  wherein  the polymer compound is further copolymerized with one or  more repeating units b each containing an adhesion group  selected from a hydroxyl group, a lactone ring, an ether  group, an ester group, a carbonyl group, a cyano group, a  sulfonate ester group, a sulfonamide group, cyclic -0----C  (=0)-S-,  and cyclic  ---0-C(=O)-NH-,  with a con› tent ratio of the repeating unit b of 0<b<l .0.  3.  The resist composition according to claim  2,  wherein  the repeating unit b contains either or both of a phenolic  hydroxyl group and a lactone ring.  4.  The resist composition according to claim  3,  wherein  the repeating unit containing the phenolic hydroxyl group is  selected from repeating units bl to b8 shown by the follow› ing general formulae (3), 