Compound for Photoacid Generator, Resist Composition Using the Same, and Pattern-Forming Method

Abstract

A sulfonic acid onium salt represented by the following formula (1) useful as a superior radiosensitive acid generator for resist compositions. It is possible to form a good pattern by using a resist composition containing this sulfonic acid onium salt corresponding to the formula (1): in which R 1 represents a monovalent organic group, and Q + represents a sulfonium cation or iodonium cation.

1 . A fluorine-containing sulfonate or fluorine-containing sulfonic acid group-containing compound, having a structure represented by the formula 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group, wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group. 
 
       
     
     
         2 . A fluorine-containing sulfonic acid onium salt represented by the following formula (1) 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group, wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group b, 
 and 
 
         wherein Q +  represents a sulfonium cation represented by the following formula (2), or an iodonium cation represented by the following formula (3), 
       
       
         
           
           
               
               
           
         
         
           wherein R 2 , R 3  and R 4  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic groups of which number of atoms is 4-30, 
           wherein any two or more of the above R 2 , R 3  and R 4  may be connected to form a ring through sulfur atom, 
         
       
       
         
           
           
               
               
           
         
         
           wherein R 5  and R 6  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic groups of which number of atoms is 4-30, and 
           wherein the above R 5  and R 6  may be connected to form a ring through iodine atom. 
         
       
     
     
         3 . A fluorine-containing sulfonic acid represented by the following formula (4) 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group, wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group b. 
 
       
     
     
         4 . A fluorine-containing sulfonate represented by the following formula (5) 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group, wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group b, and 
 M +  represents a monovalent cation. 
 
       
     
     
         5 . A photoacid generator containing a fluorine-containing sulfonic acid onium salt according to  claim 2 . 
     
     
         6 . A method for producing a fluorine-containing sulfonic acid according to  claim 3 , comprising irradiating a photoacid generator containing a fluorine-containing sulfonic acid onium salt represented by the following formula (1) 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group, wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group b, 
 and 
 
         wherein Q +  represents a sulfonium cation represented by the following formula (2), or an iodonium cation represented by the following formula (3), 
       
       
         
           
           
               
               
           
         
         
           wherein R 2 , R 3  and R 4  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic groups of which number of atoms is 4-30, 
           wherein any two or more of the above R 2 , R 3  and R 4  may be connected to form a ring through sulfur atom, 
         
       
       
         
           
           
               
               
           
         
         
           wherein R 5  and R 6  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic groups of which number of atoms is 4-30, and 
           wherein the above R 5  and R 6  may be connected to form a ring through iodine atom, 
         
         with light. 
       
     
     
         7 . A resist composition comprising a base resin, an acid generator and a solvent, wherein the acid generator is an acid generator that generates fluorine-containing sulfonic acid represented by the following formula (4) 
       
         
           
           
               
               
           
         
         wherein R 1  represents
 a C 1-10  straight-chain or branched alkyl group, wherein hydrogen atoms of the alkyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alkyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 1-10  straight-chain or branched alkenyl group having a double bond at an end portion at least, wherein hydrogen atoms of the end alkenyl group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the end alkenyl group may be replaced with a single oxygen atom to make a keto group, 
 a C 3-20  alicyclic organic group, wherein hydrogen atoms of the alicyclic organic group may partially or entirely be replaced with fluorine or hydroxyl group, and two hydrogen atoms on the same carbon constituting the alicyclic organic group may be replaced with a single oxygen atom to make a keto group, 
 a C 6-20  aryl group, a C 1-10  straight-chain or branched alkoxyl group, wherein hydrogen atoms of the alkoxyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 6-20  aryloxy group, wherein hydrogen atoms of the aryloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyl group, wherein hydrogen atoms of the alkylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyl group, wherein hydrogen atoms of the arylcarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 2-10  straight-chain or branched alkylcarbonyloxy group, wherein hydrogen atoms of the alkylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 7-20  arylcarbonyloxy group, wherein hydrogen atoms of the arylcarbonyloxy group may partially or entirely be replaced with fluorine or hydroxyl group, 
 a C 1-10  straight-chain or branched alkoxycarbonyl group, wherein hydrogen atoms of the alkoxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group, or 
 a C 7-20  aryloxycarbonyl group wherein hydrogen atoms of the aryloxycarbonyl group may partially or entirely be replaced with fluorine or hydroxyl group. 
 
       
     
     
         8 . A resist composition according to  claim 7 , wherein the acid generator that generates a fluorine-containing sulfonic acid represented by formula (4) is a fluorine-containing sulfonic acid onium salt represented by the following formula (1) 
       
         
           
           
               
               
           
         
         wherein 
         R 1  has the same meaning as that of R 1  in formula (4), 
         Q +  represents a sulfonium cation represented by the following formula (2) 
       
       
         
           
           
               
               
           
         
         
           wherein 
           R 2 , R 3  and R 4  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic group of which number of atoms is 4-30, and 
           any two or more of the above R 2 , R 3  and R 4  may be connected to form a ring through sulfur atom, 
         
         or 
         Q +  represents an iodonium cation represented by the following formula (3), 
       
       
         
           
           
               
               
           
         
         
           wherein 
           R 5  and R 6  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic group of which number of atoms is 4-30, and 
           the above R 5  and R 6  may be connected to form a ring through iodine atom. 
         
       
     
     
         9 . A resist composition according to  claim 7 , wherein the base resin is a polymer prepared by polymerizing at least one monomer selected from the group consisting of olefins, fluorine-containing olefins, acrylates, methacrylates, fluorine-containing acrylates, fluorine-containing methacrylates, norbornene compounds, fluorine-containing norbornene compounds, styrene-series compounds, fluorine-containing styrene-series compounds, vinyl ethers and fluorine-containing vinyl ethers, or copolymer prepared by copolymerizing at least two of the above monomers. 
     
     
         10 . A chemically amplified positive-type resist composition that contains:
 a base resin which is a polymer prepared by polymerizing at least one monomer selected from the group consisting of olefins, fluorine-containing olefins, acrylates, methacrylates, fluorine-containing acrylates, fluorine-containing methacrylates, norbornene compounds, fluorine-containing norbornene compounds, styrene-series compounds, fluorine-containing styrene-series compounds, vinyl ethers and fluorine-containing vinyl ethers, or copolymer prepared by copolymerizing at least two of the above monomers,   an acid generator which is a fluorine-containing sulfonic acid onium salt represented by the following formula (1)   
       
         
           
           
               
               
           
         
         wherein 
         R 1  has the same meaning as that of R 1  in formula (4), 
         Q +  represents a sulfonium cation represented by the following formula (2), 
       
       
         
           
           
               
               
           
         
         wherein 
         R 2 , R 3  and R 4  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic group of which number of atoms is 4-30, and 
         any two or more of the above R 2 , R 3  and R 4  may be connected to form a ring through sulfur atom, 
       
       or 
       Q +  represents an iodonium cation represented by the following formula (3), 
       
         
           
           
               
               
           
         
         wherein 
         R 5  and R 6  mutually independently represent C 1-30  straight-chain or branched alkyl groups optionally having substituents, C 3-30  cyclic monovalent hydrocarbon groups optionally having substituents, C 6-30  aryl groups optionally having substituents, or unsubstituted, monovalent, heterocyclic organic group of which number of atoms is 4-30, and 
         the above R 5  and R 6  may be connected to form a ring through iodine atom represented by the formula (1), 
         and a solvent, 
       
       and wherein the base resin is insoluble or poorly soluble in a developing solution and becomes soluble in the developing solution by acid. 
     
     
         11 . A pattern-forming method characterized in containing the step of applying a resist composition according to  claim 7  on a substrate, the step of exposing to a high energy ray having a wavelength of 300 nm or less through a photomask after a heating treatment, and the step of developing using a developing solution, after a heat treatment according to need. 
     
     
         12 . A pattern-forming method according to  claim 11 , wherein said method is an immersion lithography in which an ArF excimer laser of a wavelength of 193 nm is used, and in which water is inserted between wafer and a projector lens. 
     
     
         13 . Triphenylsulfonium 2-valeryloxy-1,1-difluoroethanesulfonate.