Diffusing agent composition, and method for forming an impurity diffusion layer

Abstract

A diffusing agent composition contains a condensation product (A) and an impurity diffusion component (B). The condensation product (A) is a reaction product yielded by hydrolyzing an alkoxysilane. The impurity diffusion component (B) is a monoester or diester of phosphoric acid, or a mixture thereof.

1 . A diffusing agent composition used to print an impurity diffusion component onto a semiconductor substrate, comprising:
 a condensation product (A) made from a starting material that is an alkoxysilane represented by the following general formula (1):
   [Chemical Formula 1] 
   R 1   m —SiOR 2 ) 4-m   (1)
 
   wherein   R 1  and R 2  are each an organic group, each of a plurality of R 1 s or R 2 s may be the same or different from each other, and m is 0, 1 or 2; and   an impurity diffusion component (B),   the impurity diffusion component (B) being a phosphate (C) represented by the following general formula (2):   
       
         
           
           
               
               
           
         
         wherein 
         R 3  is an alkyl group, and n is 1 or 2. 
       
     
     
         2 . The diffusing agent composition according to  claim 1 , wherein
 the content by percentage of the phosphate (C) is 50% or less by mass of the whole of the composition.   
     
     
         3 . The diffusing agent composition according to  claim 1 , wherein
 water content by percentage is 1% at most by mass of the whole of the composition.   
     
     
         4 . The diffusing agent composition according to  claim 3 , wherein
 the composition contains 0% water content.   
     
     
         5 . A method for forming an impurity diffusion layer, comprising:
 a pattern forming step of applying a diffusing agent composition as recited in  claim 1  to a semiconductor substrate, thereby forming a pattern, and   a diffusing step of diffusing the impurity diffusion component (B) of the diffusing agent composition into the semiconductor substrate.   
     
     
         6 . The method for forming an impurity diffusion layer according to  claim 5 , wherein
 the semiconductor substrate is used in a solar cell.