Resin composition, resist pattern-forming method and polymer

Abstract

A resin composition comprises a polymer comprising a structural unit that comprises a group represented by formula (1), and a solvent. In the formula (1), R 1 to R 4 each independently represent a hydrogen atom, a fluorine atom or a monovalent organic group having 1 to 20 carbon atoms, wherein at least one of R 1 to R 4 has the fluorine atom or a group including the fluorine atom. R 5 represents a substituted or unsubstituted trivalent chain hydrocarbon group having 1 to 7 carbon atoms. * denotes a binding site to other moiety of the structural unit. The structural unit is preferably represented by any one of formulae (2-1) to (2-3). In the formulae (2-1) to (2-3), Z represents a group represented by formula (1).

1 . A resin composition comprising:
 a polymer comprising a structural unit that comprises a group represented by formula (1); and   a solvent,   
       
         
           
           
               
               
           
         
         wherein, in the formula (1), 
         R 1  to R 4  each independently represent a hydrogen atom, a fluorine atom or a monovalent organic group having 1 to 20 carbon atoms, wherein at least one of R 1  to R 4  represents the fluorine atom or a group comprising the fluorine atom; 
         R 5  represents a substituted or unsubstituted trivalent chain hydrocarbon group having 1 to 7 carbon atoms; and 
         * denotes a binding site to other moiety of the structural unit. 
       
     
     
         2 . The resin composition according to  claim 1 , wherein the structural unit is represented by any one of formulae (2-1) to (2-3): 
       
         
           
           
               
               
           
         
         wherein, in the formulae (2-1) to (2-3), Z represents the group represented by the formula (1), 
         wherein, in the formula (2-1), R 6  represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, 
         wherein, in the formula (2-2), 
         R 7  represents a hydrogen atom or a methyl group; 
         R 8 , R 9  and R 10  each independently represent a hydrogen atom, a halogen atom, a hydroxy group or a monovalent organic group having 1 to 20 carbon atoms, or at least two of one or a plurality of R 8 (s) and one or a plurality of R 9 (s) and R 10  optionally taken together represent a ring structure having 3 to 20 ring atoms; 
         a is an integer of 1 to 4,
 wherein in a case where a is no less than 2, a plurality of R 8 s are identical or different with each other, and a plurality of R 9 s are identical or different with each other; and 
 
         L represents a single bond or a divalent linking group, wherein R 10  and L optionally taken together represent a ring structure having 3 to 20 ring atoms, together with the carbon atom to which R 10  and L bond, and 
         wherein, in the formula (2-3), 
         R 11  represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and E represents a single bond or a divalent linking group. 
       
     
     
         3 . The resin composition according to  claim 1 , wherein the group comprising the fluorine atom is a group represented by formula (a): 
       
         
           
           
               
               
           
         
         wherein, in the formula (a), R a  and R b  each independently represent a hydrogen atom, a fluorine atom or a monovalent organic group having 1 to 19 carbon atoms. 
       
     
     
         4 . The resin composition according to  claim 1 , wherein in the formula (1), at least one of R 3  and R 4  comprises —COO—. 
     
     
         5 . The resin composition according to  claim 1 , further comprising a radiation-sensitive acid generator. 
     
     
         6 . The resin composition according to  claim 5 , further comprising a polymer comprising a structural unit that comprises an acid-labile group, and having a lower percentage content of fluorine atoms than a percentage content of fluorine atoms of the polymer comprising the structural unit that comprises the group represented by the formula (1). 
     
     
         7 . A laminate structure comprising:
 a resist film; and   a protective film which is a cured product of the resin composition according to  claim 1 , and which is overlaid on the resist film.   
     
     
         8 . A resist pattern-forming method comprising:
 applying the resin composition according to  claim 5  directly or indirectly on a substrate to form a resist film;   exposing the resist film; and   developing the resist film exposed.   
     
     
         9 . A resist pattern-forming method comprising:
 forming a resist film;   applying the resin composition according to  claim 1  on the resist film to form a protective film overlaid on the resist film;   subjecting the resist film having the protective film overlaid thereon to liquid immersion lithography; and   developing the resist film subjected to the liquid immersion lithography.   
     
     
         10 . A polymer comprising a structural unit that comprises a group represented by formula (1): 
       
         
           
           
               
               
           
         
         wherein, in the formula (1), 
         R 1  to R 4  each independently represent a hydrogen atom, a fluorine atom or a monovalent organic group having 1 to 20 carbon atoms, wherein at least one of R 1  to R 4  represents the fluorine atom or a group comprising the fluorine atom; 
         R 5  represents a substituted or unsubstituted trivalent chain hydrocarbon group having 1 to 7 carbon atoms; and 
         * denotes a binding site to other moiety of the structural unit.