Novel ester compounds, polymers, resist compositions and patterning process

Abstract

Novel ester compounds having formula (1) wherein A 1 is a polymerizable functional group having a double bond, A 2 is furandiyl, tetrahydrofurandiyl or oxanorbornanediyl, R 1 and R 2 each are a monovalent hydrocarbon group, or R 1 and R 2 may bond together to form an aliphatic hydrocarbon ring with the carbon atom, and R 3 is hydrogen or a monovalent hydrocarbon group which may contain a hetero atom are polymerizable into polymers. Resist compositions comprising the polymers are sensitive to high-energy radiation, have an improved sensitivity, resolution, and etching resistance, and lend themselves to micropatterning with electron beams or deep-UV rays.

1 . An ester compound having the general formula (1):  
     
       
         
         
             
             
         
       
     
     wherein 
 A 1  is a polymerizable functional group having a carbon-to-carbon double bond,  
 A 2  is tetrahydrofurandiyl,  
 R 1  and R 2  bond together to form an aliphatic hydrocarbon ring with the carbon atom to which they are bonded, and  
 R 3  is hydrogen or a straight, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a hetero atom.  
 
   
   
       2 . A polymer comprising recurring units derived from the ester compound of  claim 1 .  
   
   
       3 . A polymer comprising recurring units of any one of the general formulae (1b) and (1c):  
     
       
         
         
             
             
         
       
     
     wherein 
 A 2  is a divalent group selected from among furandiyl, and tetrahydrofurandiyl,  
 R 1  and R 2  bond together to form an aliphatic hydrocarbon ring with the carbon atom to which they are bonded,  
 R 3  is hydrogen or a straight, branched, or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a hetero atom, and  
 k 1  is 0 or 1.  
 
   
   
       4 . The polymer of  claim 3 , further comprising recurring units of any one of the general formulae (M1) to (M13):  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein R 001  is hydrogen, methyl or CH 2 CO 2 R 003 ; 
 R 002  is hydrogen, methyl or CO 2 R 003 ;  
 R 003  is a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;  
 R 004  is hydrogen or a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group;  
 at least one of R 005  to R 008  represents a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group while the remaining R's independently represent hydrogen or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms, or R 005  to R 008 , taken together, may form a ring, and in that event, at least one of R 005  to R 008  is a divalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 009  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide;  
 at least one of R 010  to R 013  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently hydrogen or straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms, or R 010  to R 013 , taken together, may form a ring, and in that event, at least one of R 010  to R 013  is a divalent hydrocarbon group of 1 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 014  is a polycyclic hydrocarbon group having 7 to 15 carbon atoms or an alkyl group containing a polycyclic hydrocarbon group;  
 R 015  is an acid labile group;  
 X is CH 2  or an oxygen atom or sulfur atom;  
 Y′ is —O— or —(NR f )—;  
 R f  is hydrogen atom or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms; and  
 letter k is 0 or 1.  
 
   
   
       5 . A resist composition comprising the polymer of  claim 3 .  
   
   
       6 . A process for forming a resist pattern comprising the steps of: 
 applying the resist composition of  claim 5  onto a substrate to form a coating,    heat treating the coating and then exposing it to high-energy radiation or electron beams through a photomask, and    optionally heat treating the exposed coating and developing it with a developer.    
   
   
       7 . An ester compound having the general formula:  
     
       
         
         
             
             
         
       
     
     wherein 
 A 2  is tetrahydrofurandiyl,  
 R 1  and R 2  bond together to form an aliphatic hydrocarbon ring with the carbon atom to which they are bonded,  
 R 3  is hydrogen or a straight, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a hetero atom, and  
 R 4  is hydrogen or methyl.  
 
   
   
       8 . A polymer comprising recurring units of the general formula (1a):  
     
       
         
         
             
             
         
       
     
     wherein 
 A 2  is a divalent group selected from among furandiyl and tetrahydrofurandiyl,  
 R 1  and R 2  bond together to form an aliphatic hydrocarbon ring with the carbon atom to which they are bonded,  
 R 3  is hydrogen or a straight, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a hetero atom, and  
 R 4  is hydrogen or methyl.  
 
   
   
       9 . The polymer of  claim 8 , further comprising recurring units of any one of the general formulae (M1) to (M13):  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein 
 R 001  is hydrogen, methyl or CH 2 CO 2 R 003 ;  
 R 002  is hydrogen, methyl or CO 2 R 003 ;  
 R 003  is a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;  
 R 004  is hydrogen or a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group;  
 at least one of R 005  to R 008  represents a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group while the remaining R's independently represent hydrogen or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms, or R 005  to R 008 , taken together, may form a ring, and in that event, at least one of R 005  to R 008  is a divalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 009  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide;  
 at least one of R 010  to R 013  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently hydrogen or straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms, or R 010  to R 013 , taken together, may form a ring, and in that event, at least one of R 010  to R 013  is a divalent hydrocarbon group of 1 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 014  is a polycyclic hydrocarbon group having 7 to 15 carbon atoms or an alkyl group containing a polycyclic hydrocarbon group;  
 R 015  is an acid labile group;  
 X is CH 2  or an oxygen atom or sulfur atom;  
 Y′ is —O— or —(NR f )—;  
 R f  is hydrogen atom or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms; and  
 letter k is 0 or 1.  
 
   
   
       10 . A resist composition comprising the polymer of  claim 8 .  
   
   
       11 . A process for forming a resist pattern comprising the steps of: 
 applying the resist composition of  claim 10  onto a substrate to form a coating,    heat treating the coating and then exposing it to high-energy radiation or electron beams through a photomask, and    optionally heat treating the exposed coating and developing it with a developer.    
   
   
       12 . An ester compound selected from the group consisting of compounds having any one of the following formulae:  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
   
   
       13 . A polymer comprising recurring units derived from the ester compound of  claim 12 .  
   
   
       14 . The polymer of  claim 13 , further comprising recurring units of any one of the general formulae (M1) to (M13):  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
     wherein R 001  is hydrogen, methyl or CH 2 CO 2 R 003 ; 
 R 002  is hydrogen, methyl or CO 2 R 003 ;  
 R 003  is a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;  
 R 004  is hydrogen or a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group;  
 at least one of R 005  to R 008  represents a monovalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group while the remaining R's independently represent hydrogen or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms, or R 005  to R 008 , taken together, may form a ring, and in that event, at least one of R 005  to R 008  is a divalent hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or hydroxyl group, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 009  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide;  
 at least one of R 010  to R 013  is a monovalent hydrocarbon group of 2 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently hydrogen or straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms, or  
 R 010  to R 013 , taken together, may form a ring, and in that event, at least one of R 010  to R 013  is a divalent hydrocarbon group of 1 to 15 carbon atoms containing at least one partial structure selected from among ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide and imide, while the remaining R's are independently single bonds or straight, branched or cyclic alkylene groups of 1 to 15 carbon atoms;  
 R 014  is a polycyclic hydrocarbon group having 7 to 15 carbon atoms or an alkyl group containing a polycyclic hydrocarbon group;  
 R 015  is an acid labile group;  
 X is CH 2  or an oxygen atom or sulfur atom;  
 Y′ is —O— or —(NR f )—;  
 R f  is hydrogen atom or a straight, branched or cyclic alkyl group of 1 to 15 carbon atoms; and  
 letter k is 0 or 1.  
 
   
   
       15 . A resist composition comprising the polymer of  claim 14 .  
   
   
       16 . A process for forming a resist pattern comprising the steps of: 
 applying the resist composition of  claim 15  onto a substrate to form a coating,    heat treating the coating and then exposing it to high-energy radiation or electron beams through a photomask, and    optionally heat treating the exposed coating and developing it with a developer.    
   
   
       17 . The ester compound of  claim 1 , wherein A 1  is selected from the group consisting of vinyl, allyl, 1-propenyl, isopropenyl, and tetracyclo[4.4.0.1 2,5 .1 7,10  ]dodecyl.  
   
   
       18 . A polymer comprising recurring units derived from the ester compound of  claim 17 .  
   
   
       19 . A resist composition comprising the polymer of  claim 18.