Composition for forming p-type diffusion layer, method of forming p-type diffusion layer, and method of producing photovoltaic cell

Abstract

The composition for forming a composition for forming a p-type diffusion layer, the composition containing a glass powder and a dispersion medium, in which the glass powder includes an acceptor element and a total amount of a life time killer element in the glass powder is 1000 ppm or less. A p-type diffusion layer and a photovoltaic cell having a p-type diffusion layer are prepared by applying the composition for forming a p-type diffusion layer, followed by a thermal diffusion treatment.

1 . A composition for forming a p-type diffusion layer, the composition comprising a glass powder and a dispersion medium, wherein the glass powder includes an acceptor element and a total amount of a life time killer element in the glass powder is 1000 ppm or less. 
     
     
         2 . The composition for forming a p-type diffusion layer according to  claim 1 , wherein the acceptor element is at least one selected from boron (B), aluminum (Al) or gallium (Ga). 
     
     
         3 . The composition for forming a p-type diffusion layer according to  claim 1 , wherein the glass powder comprises:
 at least one acceptor element-containing material selected from B 2 O 3 , Al 2 O 3  or Ga 2 O 3 , and   at least one glass component material selected from SiO 2 , K 2 O, Na 2 O, Li 2 O, BaO, SrO, CaO, MgO, BeO, ZnO, PbO, CdO, Tl 2 O, SnO, ZrO 2  or MoO 3 .   
     
     
         4 . The composition for forming a p-type diffusion layer according to  claim 1 , wherein the life time killer element is at least one selected from iron (Fe), copper (Cu), nickel (Ni), manganese (Mn), chromium (Cr), tungsten (W) or gold (Au). 
     
     
         5 . A method of forming a p-type diffusion layer, the method comprising:
 applying the composition for forming a p-type diffusion layer of  claim 1 ; and   conducting a thermal diffusion treatment.   
     
     
         6 . A method of producing a photovoltaic cell, the method comprising:
 applying, on a semiconductor substrate, the composition for forming a p-type diffusion layer of  claim 1 ;   conducting a thermal diffusion treatment to form an p-type diffusion layer; and   forming an electrode on the p-type diffusion layer.