US 9,718,901 B2  68  67  Specific examples of the repeating unit having an acid› decomposable group will be shown below, but the present  invention is not limited thereto.  I  I  0  0  OH  -continued  [Chem. 23]  The polymer compound (A) may contain two or more  kinds of the repeating units (P) and the repeating units  (Q), respectively. Further, the polymer compound (A)  may contain other repeating units, in addition to the  repeating units (P) and the repeating units (Q).  For example, in the case where the composition of the  present invention is used for the formation of a so-called  positive tone pattern, the polymer compound (A) is required  to further contain a repeating unit having a group that  decomposes by the action of an acid to generate an alkali  soluble group (which may be hereinafter referred to as "a  repeating unit having an acid-decomposable group" in some  cases).  Roi and R$_{02 }$ each independently represent a hydrogen  atom, an alkyl group, a cycloalkyl group, a monovalent  aromatic ring group, a group formed by the combination of 65  an alkylene group and a monovalent aromatic ring group, or  an alkenyl group.  Examples of the group which is decomposed by the acid  include -C(R 36 )(R 37 )(R 38 ),  ----C(R 36 )(R 37 )(OR 39 ),  and  -CCR01)CR02)(OR39):  The acid-decomposable group is preferably a group 50  formed by substituting a group which eliminates a hydrogen  atom of the alkali soluble group by an acid.  Preferable examples of the alkali soluble group include a  phenolic hydroxyl group, a carboxylic group, a fluorinated  alcohol group (preferably a hexafluoroisopropanol group),  and a sulfonic acid group.  Examples of the alkali soluble group include a phenolic  hydroxyl group, a carboxylic group, a fluorinated alcohol  group, a sulfonic acid group, a sulfonamide group, a sulfo› nylimide group, an (alkylsulfonyl)(alkylcarbonyl)methylene  group, an (alkylsulfonyl)(alkylcarbonyl)imide group, a bis 40  (alkylcarbonyl)methylene group, a bis(alkylcarbonyl)imide  group, a bis(alkylsulfonyl)methylene group, a bis(alkylsul› fonyl)imide group, a tris(alkylcarbonyl)methylene group,  and a tris(alkylsulfonyl)methylene group.  wherein R 36  to R 39  each independently represent an alkyl  group, a cycloalkyl group, a monovalent aromatic ring  group, a group formed by the combination of an  alkylene group and a monovalent aromatic ring group,  or an alkenyl group. R 36  and R 37  may be bonded to each  other to form a ring.  (c) Other Repeating Units 