Solar cell front contact doping

Abstract

A method of doping solar cell front contact can improve the efficiency of CdTe-based or other kinds of solar cells.

1 - 9 . (canceled) 
     
     
         10 . A method of manufacturing a photovoltaic device comprising:
 depositing a transparent conductive oxide layer adjacent to a substrate, wherein, after the deposition, the transparent conductive oxide layer has a surface;   exposing the surface of the transparent conductive oxide layer to a dopant, wherein a dopant layer can be left on the surface;   depositing a window layer adjacent to the dopant layer;   incorporating the dopant into the window layer; and   depositing an absorber layer adjacent to the window layer, wherein the absorber layer comprises cadmium telluride.   
     
     
         11 . The method of  claim 10 , wherein depositing the window layer comprises a sputtering process. 
     
     
         12 . The method of  claim 10 , wherein exposing the surface of the transparent conductive oxide layer comprises washing the surface with a salt of the dopant. 
     
     
         13 . The method of  claim 12 , wherein the salt includes a boric-acid salt. 
     
     
         14 . The method of  claim 10 , wherein the dopant comprises an N-type dopant. 
     
     
         15 . The method of  claim 10 , wherein the dopant comprises at least one element selected from the group consisting of aluminum, indium, boron, copper, chlorine, gallium, fluorine, and magnesium. 
     
     
         16 . The method of  claim 10 , wherein the window layer comprises at least one component selected from the group consisting of cadmium sulfide, zinc telluride, cadmium zinc sulfide, zinc oxide, zinc sulfide, zinc magnesium oxide, cadmium magnesium sulfide, and cadmium oxide. 
     
     
         17 . The method of  claim 10 , wherein the window layer comprises an Mi-xGxOy semiconductor, the M is selected from the group consisting of zinc and tin, and the G is selected from the group consisting of aluminum, silicon, and zirconium. 
     
     
         18 . The method of  claim 10 , wherein depositing the window layer comprises a vapor transport deposition process. 
     
     
         19 . The method of  claim 10 , wherein depositing the window layer comprises: depositing a cadmium sulfide window layer adjacent to the dopant layer; and
 depositing a zinc-containing layer on the cadmium sulfide window layer   
     
     
         20 . The method of  claim 11 , wherein the sputtering process comprises sputtering from a ceramic target in an inert atmosphere or reactive sputtering from a metal target. 
     
     
         21 . The method of  claim 10 , further comprising an annealing step. 
     
     
         22 . A method of manufacturing a photovoltaic device comprising:
 depositing a transparent conductive oxide layer adjacent to a substrate;   depositing a window layer adjacent to the transparent conductive oxide layer by sputtering from a doped target, wherein the doped target is doped by a dopant; and   depositing an absorber layer adjacent to the window layer, wherein the absorber layer comprises cadmium telluride.   
     
     
         23 . The method of  claim 22 , further comprising:
 depositing a precursor layer adjacent to the transparent conductive oxide layer by sputtering from a doped target, wherein the doped target is doped by a dopant;   depositing a buffer layer adjacent to a precursor layer; and   annealing the precursor layer and the buffer layer to form a doped buffer layer.