Jan. 10, 2019  44  US 2019/0010119 Al  B8, and BIO. In this case, the amount of the polymer without  containing the repeating units B6, B8, and BIO 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, B8, and BIO.  [0157]  The inventive negative resist composition may  further contain a crosslinking agent to form or reinforce the  crosslinking structure of the component (B). Illustrative  examples of the crosslinking agent that can be used in the  present invention, which is not particularly limited, include  melamine compounds, guanamine compounds, glycoluril  compounds, urea compounds, epoxy compounds, isocyanate  compounds, and azide compounds, each substituted with  one or more groups selected from a methylol group, an  alkoxymethyl group, and an acyloxymethyl group; com› pounds containing a double bond(s) such as an alkenyl ether  group; and compounds containing a hydroxy group(s). They  can be used as an additive or introduced into the side chain  of a polymer as a pendant group.  [0158]  Among the specific examples of the crosslinking  agent, illustrative examples of the melamine compound  further include hexamethylol melamine, hexamethoxym› ethyl melamine, the compound of hexamethylol melamine  the 1 to 6 methylol group(s) of which are methoxymethyl› ated and mixtures thereof, hexamethoxyethyl melamine,  hexaacyloxymethyl melamine, the compound ofhexameth› ylol melamine the 1 to 6 methylol group(s) of which are  acyloxymethylated and mixtures thereof.  [0153]  The repeating units B6, B8, and BIO are units that  generates 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)  decreases the phenomenon that acid volatilizes from the  exposed portion in baking in vacuum and adheres to the  unexposed portion again, and is effective for regulating LER  and decreasing pattern defects by regulating unexpected  inhibition of the negative reaction at the unexposed portion.  The amount of the repeating units B6, B8, and BIO is  preferably 0.5 to 20 mo! % based on the whole repeating  units constituting the component (B).  [0154]  In case of preparing a chemically amplified nega› tive resist composition when the component (B) does not  contain the repeating units B6, B8, and BIO, the amount of  the repeating unit Bl is preferably 25 to 95 mo! %, more  preferably 40 to 85 mo! % based on the whole repeating  units of the component (B). The amount of the repeating unit  BN2 is preferably 5 to 70 mo!%, more preferably 10 to 60  mo!% based on the whole repeating units of the component  (B). The amount of the repeating units B3 to B5 is preferably  0 to 30 mo! %, more preferably 3 to 20 mo! % based on the  whole repeating units of the component (B). Incidentally,  other repeating units may be contained in an amount of O to  30 mo! %, preferably O to 20 mo! %.  [0155]  In case of preparing a chemically amplified nega› tive resist composition when the component (B) contains the  repeating units B6, B8, and B 10, the amount of the repeating  unit Bl is preferably 25 to 94.5 mo!%, more preferably 36  to 85 mo! % based on the whole repeating units of the  component (B). The amount of the repeating unit BN2 is  preferably 5 to 70 mo! %, more preferably 10 to 60 mo! %  based on the whole repeating units of the component (B).  The amount of the repeating units B3 to B5 is preferably 0  to 30 mo! %, more preferably 3 to 20 mo! % based on the  whole repeating units of the component (B). The total  amount of the repeating units Bl to B5 is preferably 60 to  99.5 mo! % based on the whole repeating units of the  component (B). The amount of the repeating units B6, B8,  and BIO is preferably 0.5 to 20 mo!%, more preferably 1 to  10 mo! %. Incidentally, other repeating units may be con› tained in an amount ofO to 30 mo!%, preferably Oto 20 mo!  %.  [0156]  When the inventive resist composition is a chemi› cally amplified negative resist composition, the component  (B) may be a mixture of a polymer containing the repeating  units B6, B8, and BIO in addition to the repeating unit Bl  and a polymer without containing the repeating units B6,  [0163]  Among the specific examples of the crosslinking  agent, illustrative examples of the isocyanate compound  further include tolylene diisocyanate, diphenylmethane dii› socyanate, hexamethylene diisocyanate, and cyclohexane  diisocyanate.  [0162]  Among the specific examples of the crosslinking  agent, illustrative examples of the epoxy compound further  include tris(2,3-epoxypropyl)isocyanurate, trimethylolmeth› ane triglycidyl ether, trimethylolpropane triglycidyl ether,  triethylolethane triglycidyl ether.  [0161]  Among the specific examples of the crosslinking  agent, illustrative examples of the urea compound further  include tetramethylol urea, tetramethoxymethyl urea, the  compound oftetramethylol urea the 1 to 4 methylol group(s)  of which are methoxymethylated and mixtures thereof, and  tetramethoxyethyl urea.  [0160]  Among the specific examples of the crosslinking  agent, illustrative examples of the glycoluril compound  further include tetramethylolglycoluril, tetramethoxygly› coluril, tetramethoxymethylglycoluril, the compound of  tetramethylolglycoluril the 1 to 4 methylol group(s) of  which are methoxymethylated and mixtures thereof, the  compound of tetramethylolglycoluril the 1 to 4 methylol  group(s) of which are acyloxymethylated and mixtures  thereof.  [0159]  Among the specific examples of the crosslinking  agent, illustrative examples of the guanamine compound  further include tetramethylol guanamine, tetramethoxym› ethyl guanamine, the compound oftetramethylol guanamine  the 1 to 4 methylol group(s) of which are methoxymethyl› ated and mixtures thereof, tetramethoxyethyl guanamine,  tetraacyloxy guanamine, the compound of tetramethylol  guanamine the 1 to 4 methylol group(s) of which are  acyloxymethylated and mixtures thereof.  -continued 