Positive-working radiation-sensitive composition and method for resist pattern formation using the composition

Abstract

A method of patterning using double exposure patterning in a liquid immersion lithographic process is provided. The patterning method comprises a step of forming a first pattern on a substrate using a first resist layer forming composition, a step of making the first pattern inactive, a step of forming a second pattern on a substrate on which a pattern has been formed using a second resist layer forming composition and exposing the second resist layer to radiation, and a step of developing the exposed resist layer to form a second pattern in the space area of the first pattern. The first resist layer forming composition contains a cross-linking agent which accelerates conversion of the first layer from positive-working to negative-working.

1 . A positive-working radiation-sensitive resin composition comprising (A) a crosslinking agent, (B1) a polymer containing an acid-unstable group (not containing a crosslinking group), (C) a radiation-sensitive acid generator, and (D) a solvent, the positive-working radiation-sensitive resin composition being used for forming a first resist layer used in a method of forming a resist pattern which comprises: 
     (1) a step of forming a first resist pattern by forming a first resist layer on a substrate using the positive-working radiation-sensitive resin composition for forming the first resist layer, selectively exposing the first resist layer to radiation through a mask, and developing the exposed first resist layer, 
     (2) a step of making the first resist pattern inactive to radiation or insolubilizing the first resist pattern in an alkaline developer or a positive-working radiation-sensitive resin composition for forming a second resist layer, 
     (3) a step of forming a second resist layer on the substrate on which the first resist pattern has been formed using the positive-working radiation-sensitive resin composition for forming the second resist layer, and selectively exposing the second resist layer to radiation through a mask in the space area of the first resist pattern, and 
     (4) a step of forming a second resist pattern in the space area of the first resist pattern by developing the exposed second resist layer. 
   
   
       2 . The positive-working radiation-sensitive resin composition according to  claim 1 , wherein the crosslinking agent (A) is:
 a compound having two or more groups shown by the following formula (1),   
     
       
         
         
             
             
         
       
     
     wherein R 1  and R 2  represent a hydrogen atom or a group shown by the following formula (2), at least one of R 1  and R 2  being a group shown by the following formula (2), 
     
       
         
         
             
             
         
       
     
     wherein R 3  and R 4  represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxyalkyl group having 1 to 6 carbon atoms, or R 3  and R 4  bond together to form a ring having 2 to 10 carbon atoms, and R 5  represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,
 a compound having two or more epoxy groups or oxetane groups, or 
 a compound having two or more vinyl groups and a skeleton shown by any one of the following formulas (12-1) to (12-4). 
 
     
       
         
         
             
             
         
       
     
   
   
       3 - 10 . (canceled) 
   
   
       11 . The positive-working radiation-sensitive resin composition according to  claim 1 , wherein the amount of the crosslinking agent (A) is 1 to 30 mass % of the solid component of the composition. 
   
   
       12 . The positive-working radiation-sensitive resin composition according to  claim 2 , wherein the amount of the crosslinking agent (A) is 1 to 30 mass % of the solid component of the composition. 
   
   
       13 . The positive-working radiation-sensitive resin composition according to  claim 1 , wherein the polymer (B1) has:
 a repeating unit which contains an acid-unstable group shown by the following formula (3),   
     
       
         
         
             
             
         
       
     
     wherein R 6  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 7  individually represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, a derivative thereof, or a linear or branched alkyl group having 1 to 4 carbon atoms, and
 a repeating unit which contains a lactone structure shown by at least one of the following formulas (4-1) to (4-6), 
 
     
       
         
         
             
             
         
       
     
     wherein R 8  represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R 9  represents a hydrogen atom or a methoxy group, A represents a single bond or a methylene group, B represents an oxygen atom or a methylene group, p is an integer of 1 to 3, and m is 0 or 1. 
   
   
       14 . The positive-working radiation-sensitive resin composition according to  claim 2 , wherein the polymer (B1) has:
 a repeating unit which contains an acid-unstable group shown by the following formula (3),   
     
       
         
         
             
             
         
       
     
     wherein R 6  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 7  individually represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, a derivative thereof, or a linear or branched alkyl group having 1 to 4 carbon atoms, and
 a repeating unit which contains a lactone structure shown by at least one of the following formulas (4-1) to (4-6), 
 
     
       
         
         
             
             
         
       
     
     wherein R 8  represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R 9  represents a hydrogen atom or a methoxy group, A represents a single bond or a methylene group, B represents an oxygen atom or a methylene group, p is an integer of 1 to 3, and m is 0 or 1. 
   
   
       15 . The positive-working radiation-sensitive resin composition according to  claim 11 , wherein the polymer (B1) has:
 a repeating unit which contains an acid-unstable group shown by the following formula (3),   
     
       
         
         
             
             
         
       
     
     wherein R 6  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 7  individually represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, a derivative thereof, or a linear or branched alkyl group having 1 to 4 carbon atoms, and
 a repeating unit which contains a lactone structure shown by at least one of the following formulas (4-1) to (4-6), 
 
     
       
         
         
             
             
         
       
     
     wherein R 8  represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R 9  represents a hydrogen atom or a methoxy group, A represents a single bond or a methylene group, B represents an oxygen atom or a methylene group, p is an integer of 1 to 3, and m is 0 or 1. 
   
   
       16 . The positive-working radiation-sensitive resin composition according to  claim 12 , wherein the polymer (B1) has:
 a repeating unit which contains an acid-unstable group shown by the following formula (3),   
     
       
         
         
             
             
         
       
     
     wherein R 6  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 7  individually represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, a derivative thereof, or a linear or branched alkyl group having 1 to 4 carbon atoms, and
 a repeating unit which contains a lactone structure shown by at least one of the following formulas (4-1) to (4-6), 
 
     
       
         
         
             
             
         
       
     
     wherein R 8  represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R 9  represents a hydrogen atom or a methoxy group, A represents a single bond or a methylene group, B represents an oxygen atom or a methylene group, p is an integer of 1 to 3, and m is 0 or 1. 
   
   
       17 . A positive-working radiation-sensitive resin composition comprising (B2) a polymer containing a crosslinking group and an acid-unstable group, (C) a radiation-sensitive acid generator, and (D) a solvent, the positive-working radiation-sensitive resin composition being used for forming a first resist layer used in a method of forming a resist pattern which comprises: 
     (1) a step of forming a first resist pattern by forming a first resist layer on a substrate using the positive-working radiation-sensitive resin composition for forming the first resist layer, selectively exposing the first resist layer to radiation through a mask, and developing the exposed first resist layer, 
     (2) a step of making the first resist pattern inactive to radiation or insolubilizing the first resist pattern in an alkaline developer or a positive-working radiation-sensitive resin composition for forming a second resist layer 
     (3) a step of forming a second resist layer on the substrate on which the first resist pattern has been formed using the positive-working radiation-sensitive resin composition for forming the second resist layer and selectively exposing the second resist layer to radiation through a mask in the space area of the first resist pattern, and 
     (4) a step of forming a second resist pattern in the space area of the first resist pattern by developing the exposed second resist layer. 
   
   
       18 . The positive-working radiation-sensitive resin composition according to  claim 17 , wherein the polymer (B2) has:
 a repeating unit which contains an acid-unstable group shown by the following formula (3),   
     
       
         
         
             
             
         
       
     
     wherein R 6  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 7  individually represents a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, a derivative thereof, or a linear or branched alkyl group having 1 to 4 carbon atoms, and
 a repeating unit which contains a lactone structure shown by at least one of the following formulas (4-1) to (4-6), 
 
     
       
         
         
             
             
         
       
     
     wherein R 8  represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, R 9  represents a hydrogen atom or a methoxy group, A represents a single bond or a methylene group, B represents an oxygen atom or a methylene group, p is an integer of 1 to 3, and m is 0 or 1. 
   
   
       19 . The positive-working radiation-sensitive resin composition according  claim 17 , wherein the polymer (B2) contains at least one repeating unit shown by the following formulas (5-1) or (5-2), 
     
       
         
         
             
             
         
       
     
     wherein, R 10  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, D represents a methylene group, an ethylene group, or a propylene group; and R 11  is a group shown by the following formula (5-1-A) or the following formula (5-1-B), 
     
       
         
         
             
             
         
       
     
     wherein, R 10  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 12  represents a methylene group or an alkylene group having 2 to 6 carbon atoms, R 13  represents a hydrogen atom, a methyl group, or an ethyl group, and n is 0 or 1. 
   
   
       20 . The positive-working radiation-sensitive resin composition according  claim 18 , wherein the polymer (B2) contains at least one repeating unit shown by the following formulas (5-1) or (5-2), 
     
       
         
         
             
             
         
       
     
     wherein, R 10  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, D represents a methylene group, an ethylene group, or a propylene group; and R 11  is a group shown by the following formula (5-1-A) or the following formula (5-1-B), 
     
       
         
         
             
             
         
       
     
     wherein, R 10  represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 12  represents a methylene group or an alkylene group having 2 to 6 carbon atoms, R 13  represents a hydrogen atom, a methyl group, or an ethyl group, and n is 0 or 1. 
   
   
       21 . The positive-working radiation-sensitive resin composition according to  claim 19 , containing the repeating unit shown by the above formulas (5-1) or (5-2) in an amount of 1 to 30 mol % of 100 mol % of the total polymer component in the positive-working radiation-sensitive resin composition. 
   
   
       22 . The positive-working radiation-sensitive resin composition according to  claim 20 , containing the repeating unit shown by the above formulas (5-1) or (5-2) in an amount of 1 to 30 mol % of 100 mol % of the total polymer component in the positive-working radiation-sensitive resin composition. 
   
   
       23 . A method for forming a pattern comprising: 
     (1) a step of forming a first resist pattern by forming a first resist layer on a substrate using a positive-working radiation-sensitive resin composition for forming the first resist layer, selectively exposing the first resist layer to radiation through a mask, and developing the exposed first resist layer, 
     (2) a step of making the first resist pattern inactive to radiation or insolubilizing the first resist pattern in an alkaline developer or a positive-working radiation-sensitive resin composition for forming a second resist layer 
     (3) a step of forming a second resist layer on the substrate on which the first resist pattern has been formed using the positive-working radiation-sensitive resin composition for forming the second resist layer and selectively exposing the second resist layer to radiation through a mask in the space area of the first resist pattern, and 
     (4) a step of forming a second resist pattern in the space area of the first resist pattern by developing the exposed second resist layer,
 the positive-working radiation-sensitive resin composition for forming the first resist layer being the composition according to  claim 1 . 
 
   
   
       24 . A method for forming a pattern comprising: 
     (1) a step of forming a first resist pattern by forming a first resist layer on a substrate using a positive-working radiation-sensitive resin composition for forming the first resist layer, selectively exposing the first resist layer to radiation through a mask, and developing the exposed first resist layer, 
     (2) a step of making the first resist pattern inactive to radiation or insolubilizing the first resist pattern in an alkaline developer or a positive-working radiation-sensitive resin composition for forming a second resist layer 
     (3) a step of forming a second resist layer on the substrate on which the first resist pattern has been formed using the positive-working radiation-sensitive resin composition for forming the second resist layer and selectively exposing the second resist layer to radiation through a mask in the space area of the first resist pattern, and 
     (4) a step of forming a second resist pattern in the space area of the first resist pattern by developing the exposed second resist layer,
 the positive-working radiation-sensitive resin composition for forming the first resist layer being the composition according to  claim 17 . 
 
   
   
       25 . The method for forming a pattern according to  claim 23 , wherein the step of making the first resist pattern inactive to radiation comprises making inactive to heating at a 140° C. or higher temperature or to radiation at a wavelength of not more than 300 nm. 
   
   
       26 . The method for forming a pattern according to  claim 24 , wherein the step of making the first resist pattern inactive to radiation comprises making inactive to heating at a 140° C. or higher temperature or to radiation at a wavelength of not more than 300 nm.