Metal Dendrite-free Solar Cell

Abstract

A solar cell assembly including a semiconductor wafer having a solar cell portion and a wing portion, wherein the wing portion is electrically isolated from the solar cell portion, and an electrical contact material positioned on the solar cell portion, wherein the wing portion is substantially free of the electrical contact material.

What is claimed is: 
     
         1 . A solar cell assembly comprising:
 a semiconductor wafer comprising a solar cell portion and a wing portion, wherein said wing portion is electrically isolated from said solar cell portion; and   an electrical contact material positioned on said solar cell portion,   wherein said wing portion is substantially free of said electrical contact material.   
     
     
         2 . The solar cell assembly of  claim 1  wherein said electrical contact material comprises silver. 
     
     
         3 . The solar cell assembly of  claim 1  wherein said electrical contact material is arranged in a grid pattern. 
     
     
         4 . The solar cell assembly of  claim 3  wherein said grid pattern comprises a plurality of grid lines. 
     
     
         5 . The solar cell assembly of  claim 4  wherein at least one grid line of said plurality of grid lines comprises a tip, wherein said tip protrudes toward said wing portion. 
     
     
         6 . The solar cell assembly of  claim 3  wherein said grid pattern comprises a bus bar and a plurality of grid lines. 
     
     
         7 . The solar cell assembly of  claim 6  wherein at least one grid line of said plurality of grid lines comprises an outer end, and wherein said bus bar is positioned between said outer end and said wing portion. 
     
     
         8 . A solar cell separated from said solar cell assembly of  claim 1 . 
     
     
         9 . A solar cell assembly comprising:
 a semiconductor wafer comprising a solar cell portion and a wing portion, wherein said wing portion is electrically isolated from said solar cell portion;   a first electrical contact material positioned on said solar cell portion; and   a second electrical contact material positioned on said wing portion,   wherein said first electrical contact material is spaced at least 1 millimeter from said second electrical contact material.   
     
     
         10 . The solar cell assembly of  claim 9  wherein said solar cell portion is separated from said wing portion by a spacer zone, and wherein said spacer zone is substantially free of said first electrical contact material and said second electrical contact material. 
     
     
         11 . The solar cell assembly of  claim 9  wherein said first electrical contact material is spaced at least 1.5 millimeters from said second electrical contact material. 
     
     
         12 . The solar cell assembly of  claim 9  wherein said first electrical contact material is spaced at least 2 millimeters from said second electrical contact material. 
     
     
         13 . The solar cell assembly of  claim 9  wherein said first electrical contact material is spaced at least 2.5 millimeters from said second electrical contact material. 
     
     
         14 . The solar cell assembly of  claim 9  wherein said first electrical contact material is spaced at least 3 millimeters from said second electrical contact material. 
     
     
         15 . The solar cell assembly of  claim 9  wherein both said first electrical contact material and said second electrical contact material comprise silver. 
     
     
         16 . The solar cell assembly of  claim 9  wherein said first electrical contact material is arranged in a grid pattern. 
     
     
         17 . The solar cell assembly of  claim 16  wherein said grid pattern comprises a plurality of grid lines. 
     
     
         18 . The solar cell assembly of  claim 17  wherein at least one grid line of said plurality of grid lines comprises a tip, wherein said tip protrudes toward said wing portion. 
     
     
         19 . The solar cell assembly of  claim 16  wherein said grid pattern comprises a bus bar and a plurality of grid lines. 
     
     
         20 . The solar cell assembly of  claim 19  wherein at least one grid line of said plurality of grid lines comprises an outer end, and wherein said bus bar is positioned between said outer end and said wing portion.