Jan. 10, 2019  35  US 2019/0010119 Al  (Negative Resist Composition)  wherein  RA  has the same meaning as defined above; each  R  12  independently represents a halogen atom, a linear,  branched, or cyclic acyloxy group having 2 to 8 carbon  atoms optionally substituted with a halogen atom, a linear,  branched, or cyclic alkyl group having 1 to 6 carbon atoms  optionally substituted with a halogen atom, or a linear,  branched, or cyclic alkoxy group having 1 to 6 carbon atoms  optionally substituted with a halogen atom; A $^{2 }$represents a  single bond or a linear, branched, or cyclic alkylene group  having 1 to 10 carbon atoms optionally having an ether bond  between a carbon-carbon bond thereof; W represents a  hydrogen atom, a linear, branched, or cyclic monovalent  aliphatic hydrocarbon group having 1 to 10 carbon atoms  optionally having an ether group, a carbonyl group, or a  carbonyloxy group between a carbon-carbon bond thereof,  or a monovalent aromatic ring group optionally having a  substituent; Rx and Ry each independently represent a  hydrogen atom, an alkyl group having 1 to 15 carbon atoms  optionally substituted with a hydroxy group or an alkoxy  group, or a monovalent aromatic ring group optionally  having a substituent, with the proviso that Rx and Ry do not  both represent hydrogen atoms, and Rx and Ry are option› ally bonded with each other to form a ring together with the  carbon atom to which  Rx and Ry are bonded; "y" is an  [0133]  When the inventive resist composition is a chemi› cally amplified positive resist composition, the component  (B) may be a mixture of a polymer containing the repeating  units B6 to B9 in addition to the repeating unit Bl and a  polymer without containing the repeating units B6 to B9. In  this case, the amount of the polymer without containing the  repeating units B6 to B9 is preferably 2 to 5,000 parts by  mass, more preferably 10 to 1,000 based on 100 parts by  mass of the polymer containing the repeating units B6 to B9.  [0132]  The repeating units B6 to B9 are units that gener› ates an acid by irradiation with a high energy beam.  It is  considered that these units contained in the component (B)  makes it possible to regulate the acid diffusion appropriately  to give a pattern with decreased LER. Additionally, it is  considered that these units contained in the component (B)  regulates the phenomenon that acid volatilizes from the  exposed portion in baking in vacuum and adheres to the  unexposed portion again, and is effective for decreasing  LER and decreasing pattern defects by regulating an unde› sired deprotection reaction at the unexposed portion. When  the repeating unit B6 to B9 is contained, the amount is  preferably 0.5 to 30 mo!  % based on the whole repeating  units of the component (B).  [0136]  In this case, it is preferable that the component (B)  further contain a repeating unit shown by the following  general formula (BN2) (hereinafter, also referred to as the  repeating unit BN2) in addition to the repeating unit (Bl)  [0135]  When the inventive resist composition is a chemi› cally amplified negative resist composition, the repeating  unit Bl is preferably contained in an amount ranging from  the lower limit of 40 mo! %, more preferably 50 mo! %, to  the upper limit of 100 mo! %, preferably 85 mo! % with  respect to the whole repeating units of the component (B) in  order to bring higher contrast between the portion that is  turned to negative by exposure to a high energy beam and  the portion without being exposed (the portion that is not  turned to negative) for obtaining higher resolution.  [0134]  When the inventive resist composition is a chemi› cally amplified negative resist composition, the composition  preferably contains a resin (polymer compound) that  becomes alkaline-insoluble as a base polymer of the com› ponent (B). As this resin to become alkaline-insoluble by an  action of acid, which is not particularly limited, it is pref› erable to use the ones in which the resins form crosslinking  with each other by an action of acid to be polymerized or the  ones that react with a crosslinking agent described later by  an action of acid to be polymerized.  -continued  o/’--...../0..........._  c¢  ()  0  o/’--...../0..........._  c¢  0  aLO  0  0  (BN2) 