Oct. 21, 2010  25  US 2010/0266955 Al  represented by formulas (al-1-16), (al-1-17) and (al-1-20)  to (al-1-23), structural units represented by general formula  (al-3-01) shown below which include the structural units  represented by formulas (al-3-25) and (al-3-26), and struc› tural units represented by general formula (al-3-02) shown  below which include the structural units represented by for› mulas (al-3-27) and (al-3-28) are also preferable.  [Chemical Formula 25]  (al-3-01)  [Chemical Formula 23]  (al-1-01)  In the formula, R represents a hydrogen atom, an alkyl group  of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5  carbon atoms;  R  $^{14 }$represents an alkyl group; R $^{13 }$represents a  hydrogen atom or a methyl group; and a represents an integer  of 1 to 10.  [Chemical Formula 26]  (al-3-02)  In the formula, R represents a hydrogen atom, an alkyl group  of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5  carbon atoms; and R$^{11 }$represents an alkyl group of 1 to 5  carbon atoms.  [Chemical Formula 24]  (al-1-02)  In the formula, R represents a hydrogen atom, an alkyl group  of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5  carbon atoms; R $^{14 }$represents an alkyl group; R $^{13 }$represents a  hydrogen atom or a methyl group; a represents an integer of 1  to 1 0; and g represents an integer of 0 to 8.  [0173]  In general formulas (al-3-01) and (al-3-02), R, R 13 ,  R 14 , a and g are the same as defined above.  [0174]  R$^{13 }$is preferably a hydrogen atom.  [0175]  The alkyl group for R $^{14 }$is preferably a linear or  branched alkyl group, more preferably a linear alkyl group,  and most preferably a methyl group or an ethyl group,  [0176]  a is preferably an integer of 1 to 8, more preferably  1 to 5, and most preferably 1 or 2.  [0177]  g is preferably an integer of0 to 3, more preferably  1 to 3, and still more preferably 1 or 2.  [0178]  In the component (Al), the amount of the structural  unit (al) based oil the combined total of all structural units  constituting the component (Al) is preferably 3 to 80 mo! %,  more preferably 5 to 70 mo!%, and still more preferably 10 to  50 mo!%. When the amount of the structural unit (al) is at  least as large as the lower limit of the above-mentioned range,  a pattern can be easily formed using a resist composition  prepared from the component (Al). On the other hand, when  the amount of the structural unit ( a 1) is no more than the upper  limit of the above-mentioned range, a good balance can be  achieved with the other structural units.  [0179]  The monomers for deriving the structural units rep› resented by general formulas (al-3-01) and (al-3-02) above  (hereafter, these monomers are collectively referred to as  "monomer W") can be produced by a production method  shown below  In the formula, R represents a hydrogen atom, an alkyl group  of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5  carbon atoms;  R  $^{12 }$represents an alkyl group of 1 to 5 carbon  atoms; and h represents an integer of 1 to 6.  [0168]  In general formula (al-1-01), R is the same as  defined above.  [0169]  The alkyl group for R$^{11 }$is the same as defined for the  alkyl group represented by R, and is preferably a methyl  group or an ethyl group.  [0170]  In general formula (al-1-02), R is the same as  defined above.  [0171]  The alkyl group for R$^{12 }$is the same as defined for the  alkyl group represented by R, preferably a methyl group or an  ethyl group, and most preferably an ethyl group.  [0172]  his preferably 1 or 2, and most preferably 2. 