Silphenylene-containing photocurable composition, pattern formation method using same, and optical semiconductor element obtained using the method

Abstract

Provided is a silphenylene-containing photocurable composition including: (A) a specific silphenylene having both terminals modified with alicyclic epoxy groups, and (C) a photoacid generator that generates acid upon irradiation with light having a wavelength of 240 to 500 nm. Also provided is a pattern formation method including: (i) forming a film of the photocurable composition on a substrate, (ii) exposing the film through a photomask with light having a wavelength of 240 to 500 nm, and if necessary, performing heating following the exposure, and (iii) developing the film in a developing liquid, and if necessary, performing post-curing at a temperature within a range from 120 to 300° C. following the developing. Further provided is an optical semiconductor element obtained by performing pattern formation using the method. The composition is capable of very fine pattern formation across a broad range of wavelengths, and following pattern formation, yields a film that exhibits a high degree of transparency and superior light resistance. The composition may also include: (B) a specific epoxy group-containing organosilicon compound.

1 . A silphenylene-containing photocurable composition comprising:
 (A) a silphenylene having both terminals modified with alicyclic epoxy groups, represented by formula (1) shown below, and   
       
         
           
           
               
               
           
         
         (C) a photoacid generator that generates acid upon irradiation with light having a wavelength of 240 to 500 nm. 
       
     
     
         2 . The silphenylene-containing photocurable composition according to  claim 1 , wherein an amount of component (C) is within a range from 0.05 to 20 parts by mass per 100 parts by mass of component (A). 
     
     
         3 . The silphenylene-containing photocurable composition according to  claim 1 , further comprising:
 (D) an organic solvent, in an amount of 1 to 2,000 parts by mass per 100 parts by mass of a combined mass of component (A) and component (C).   
     
     
         4 . The silphenylene-containing photocurable composition according to  claim 1 , further comprising:
 (B) an epoxy group-containing organosilicon compound represented by general formula (2) shown below:   
       
         
           
           
               
               
           
         
       
       wherein each R independently represents a hydrogen atom or a monovalent organic group, at least one R comprises an epoxy group, a, b and c each represents an integer of 0 or greater, d represents an integer of 0 or greater, e represents an integer of 1 or greater, W, X and Y each represents a divalent organic group, and f, g and h each independently represents 0 or 1, provided that when a and c are 0, b is 1 and g is 0, the R groups do not both represent epoxy group-containing organic groups represented by the formula below. 
       
         
           
           
               
               
           
         
       
     
     
         5 . The silphenylene-containing photocurable composition according to  claim 4 , wherein an amount of component (B) is within a range from 0.5 to 900 parts by mass per 100 parts by mass of component (A), and an amount of component (C) is within a range from 0.05 to 20 parts by mass per 100 parts by mass of a combined mass of component (A) and component (B). 
     
     
         6 . The silphenylene-containing photocurable composition according to  claim 4 , further comprising:
 (D) an organic solvent, in an amount of 1 to 2,000 parts by mass per 100 parts by mass of a combined mass of components (A), (B) and (C).   
     
     
         7 . The silphenylene-containing photocurable composition according to  claim 4 , wherein component (B) is an epoxy group-containing organosilicon compound represented by general formula (2′) shown below: 
       
         
           
           
               
               
           
         
       
       wherein a′, b′ and c′ each represents an integer of 0 or greater, R, d, e, W, X and Y are as defined above, and Z represents a divalent organic group represented by a formula shown below: 
       
         
           
           
               
               
           
         
         wherein R, d and e are as defined above, 
       
       provided that when a′, b′ and c′ are 0 and Z is a divalent organic group represented by a formula shown below: 
       
         
           
           
               
               
           
         
       
       the R groups do not both represent epoxy group-containing organic groups represented by a formula below. 
       
         
           
           
               
               
           
         
       
     
     
         8 . The silphenylene-containing photocurable composition according to  claim 4 , wherein each R independently represents a hydrogen atom, a monovalent hydrocarbon group of 1 to 8 carbon atoms, or an epoxy group-containing organic group represented by a formula shown below: 
       
         
           
           
               
               
           
         
       
       and at least one R comprises an epoxy group. 
     
     
         9 . The silphenylene-containing photocurable composition according to  claim 4 , wherein W, X and Y each represents a divalent organic group represented by general formula (3) shown below: 
       
         
           
           
               
               
           
         
       
       wherein i represents an integer of 0 to 10. 
     
     
         10 . The silphenylene-containing photocurable composition according to  claim 1 , wherein the component (C) is at least one photoacid generator selected from the group consisting of onium salts, diazomethane derivatives, glyoxime derivatives, β-ketosulfone derivatives, disulfone derivatives, nitrobenzyl sulfonate derivatives, sulfonate ester derivatives, imidoyl sulfonate derivatives, oxime sulfonate derivatives, iminosulfonate derivatives and triazine derivatives. 
     
     
         11 . The silphenylene-containing photocurable composition according to  claim 4 , wherein the component (C) is at least one photoacid generator selected from the group consisting of onium salts, diazomethane derivatives, glyoxime derivatives, β-ketosulfonederivatives, disulfone derivatives, nitrobenzyl sulfonate derivatives, sulfonate ester derivatives, imidoyl sulfonate derivatives, oxime sulfonate derivatives, iminosulfonate derivatives and triazine derivatives. 
     
     
         12 . A cured film obtained by curing the silphenylene-containing photocurable composition defined in  claim 1 . 
     
     
         13 . A cured film obtained by curing the silphenylene-containing photocurable composition defined in  claim 4 . 
     
     
         14 . A pattern formation method comprising:
 (i) forming a film of the photocurable composition defined in  claim 1  on a substrate,   (ii) exposing the film through a photomask with light having a wavelength of 240 to 500 nm, or exposing the film through a photomask with light having a wavelength of 240 to 500 nm and then performing heating following the exposure, and   (iii) developing the film in a developing liquid, or developing the film in a developing liquid and subsequently performing post-curing at a temperature within a range from 120 to 300° C.   
     
     
         15 . A pattern formation method comprising:
 (i) forming a film of the photocurable composition defined in  claim 4  on a substrate,   (ii) exposing the film through a photomask with light having a wavelength of 240 to 500 nm, or exposing the film through a photomask with light having a wavelength of 240 to 500 nm and then performing heating following the exposure, and   (iii) developing the film in a developing liquid, or developing the film in a developing liquid and subsequently performing post-curing at a temperature within a range from 120 to 300° C.   
     
     
         16 . An optical semiconductor element obtained by performing pattern formation using the method defined in  claim 14 . 
     
     
         17 . The optical semiconductor element according to  claim 16 , having a cured film obtained by curing the photocurable composition. 
     
     
         18 . An optical semiconductor element obtained by performing pattern formation using the method defined in  claim 15 . 
     
     
         19 . The optical semiconductor element according to  claim 18 , having a cured film obtained by curing the photocurable composition.