Selective emitter solar cell

Abstract

A selective emitter solar cell is discussed. The selective emitter solar cell includes a substrate of a first conductive type, an emitter layer of a second conductive type positioned on a light receiving surface of the substrate, and a plurality of first electrodes that are positioned on the emitter layer and are electrically connected to the emitter layer. The emitter layer includes a first emitter portion having a first impurity concentration and a second emitter portion having a second impurity concentration higher than the first impurity concentration. The second emitter portion includes a first region that directly contacts at least one of the plurality of first electrodes and overlaps the at least one of the plurality of first electrodes and a second region that is positioned around the first region and does not overlap the at least one of the plurality of first electrodes. A line width of the second region is equal to or less than about eight times a line width of each of the plurality of first electrodes.

1 . A selective emitter solar cell, comprising:
 a substrate of a first conductive type;   an emitter layer of a second conductive type, and positioned on a light receiving surface of the substrate; and   a plurality of first electrodes that are positioned on the emitter layer and are electrically connected to the emitter layer,   wherein the emitter layer includes a first emitter portion having a first impurity concentration and a second emitter portion having a second impurity concentration higher than the first impurity concentration,   the second emitter portion includes a first region that directly contacts at least one of the plurality of first electrodes and overlaps the at least one of the plurality of first electrodes, and a second region that is positioned around the first region and does not overlap the at least one of the plurality of first electrodes, and   a line width of the second region is equal to or less than about eight times a line width of each of the plurality of first electrodes.   
     
     
         2 . The selective emitter solar cell of  claim 1 , wherein the line width of each first electrode is substantially equal to a line width of the first region. 
     
     
         3 . The selective emitter solar cell of  claim 2 , wherein a thickness of the second emitter portion is greater than a thickness of the first emitter portion. 
     
     
         4 . The selective emitter solar cell of  claim 3 , wherein an upper surface of the first emitter portion and an upper surface of the second emitter portion are positioned on the same plane. 
     
     
         5 . The selective emitter solar cell of  claim 3 , wherein a lower surface of the first emitter portion and a lower surface of the second emitter portion are positioned on the same plane. 
     
     
         6 - 19 . (canceled) 
     
     
         20 . The selective emitter solar cell of  claim 2 , wherein two portions of the second region are respectively positioned at both sides of the first region. 
     
     
         21 . The selective emitter solar cell of  claim 20 , wherein a sum of line widths of the two portions of second region respectively positioned at the both sides of the first region is equal to or greater than the line width of each first electrode. 
     
     
         22 . The selective emitter solar cell of  claim 21 , wherein the sum of the line widths of the two portions of second region is equal to or less than about four times the line width of each first electrode. 
     
     
         23 . The selective emitter solar cell of  claim 20 , wherein the line width of each first electrode is approximately 40 μm to 100 μm. 
     
     
         24 . The selective emitter solar cell of  claim 20 , wherein the two portions of the second region respectively positioned at the both sides of the first region have substantially the same line width or each have different line widths. 
     
     
         25 . The selective emitter solar cell of  claim 20 , further comprising at least one first current collector that is positioned on the emitter layer in a direction crossing the plurality of first electrodes and is electrically connected to the emitter layer,
 wherein the second emitter portion further includes a third region that directly contacts the at least one first current collector and overlaps the at least one first current collector, and a fourth region that is positioned around the third region and does not overlap the at least one first current collector.   
     
     
         26 . The selective emitter solar cell of  claim 25 , wherein a sum of a line width of the third region and a line width of the fourth region is 1.01 to 1.4 times a line width of the at least one first current collector. 
     
     
         27 . The selective emitter solar cell of  claim 25 , wherein a line width of the at least one first current collector is substantially equal to a line width of the third region. 
     
     
         28 . The selective emitter solar cell of  claim 27 , wherein the fourth region is positioned at one side of the third region. 
     
     
         29 . The selective emitter solar cell of  claim 28 , wherein a line width of the fourth region is 0.01 to 0.4 times the line width of the at least one first current collector. 
     
     
         30 . The selective emitter solar cell of  claim 28 , wherein a line width of the fourth region is substantially equal to the line width of the second region. 
     
     
         31 . The selective emitter solar cell of  claim 27 , wherein two portions of the fourth region are respectively positioned at both sides of the third region. 
     
     
         32 . The selective emitter solar cell of  claim 31 , wherein the two portions of the fourth region respectively positioned at the both sides of the third region have substantially the same line width or each have different widths. 
     
     
         33 . The selective emitter solar cell of  claim 31 , wherein a sum of line widths of the two portions of the fourth region respectively positioned at the both sides of the third region is 0.01 to 0.4 times the line width of the at least one first current collector. 
     
     
         34 . The selective emitter solar cell of  claim 31 , wherein a sum of line widths of the two portions of the fourth region respectively positioned at the both sides of the third region is substantially equal to a sum of line widths of the two portions of the second region respectively positioned at the both sides of the first region.