Method of manufacturing solar cell electrode and conductive paste

Abstract

The present invention relates to a method of manufacturing a solar cell electrode, comprising: preparing a semiconductor substrate having a preformed electrode on a front side, a back side, or both of the front and the back side of the semiconductor substrate; applying a conductive paste onto the preformed electrode, wherein the conductive paste comprises a conductive powder, an amorphous saturated polyester resin with glass transitional temperature (Tg) of 50° C. or lower, and an organic solvent; drying the applied conductive paste; putting a tab electrode on the dried conductive paste; and soldering the tab electrode.

We claim: 
     
         1 . A method of manufacturing a solar cell electrode comprising steps of:
 preparing a semiconductor substrate having a preformed electrode on a front side, a back side, or both of the front and the back side of the semiconductor substrate;   applying a conductive paste onto the preformed electrode, wherein the conductive paste comprises a conductive powder, an amorphous saturated polyester resin with glass transitional temperature (Tg) of 50° C. or lower, and an organic solvent;   drying the applied conductive paste;   putting a tab electrode on the dried conductive paste; and   soldering the tab electrode.   
     
     
         2 . The method of manufacturing a solar cell electrode of  claim 1 , wherein the conductive powder is from 40 to 90 weight percent, the amorphous saturated polyester resin is from 3 to 20 weight percent, and the organic solvent is 5 to 50 weight percent, based on the total weight of the conductive paste. 
     
     
         3 . The method of manufacturing a solar cell electrode of  claim 1 , wherein the preformed electrode is a transparent electrode. 
     
     
         4 . The method of manufacturing a solar cell electrode of  claim 1 , wherein the preformed electrode is a collective electrode comprising a bus bar and a finger line at the front side of the semiconductor substrate. 
     
     
         5 . The method of manufacturing a solar cell electrode of  claim 1 , wherein the preformed electrode is a backside electrode on the back side of the semiconductor substrate. 
     
     
         6 . The method of manufacturing a solar cell electrode of  claim 1 , wherein the conductive paste is dried at from 80 to 250° C. at the drying step. 
     
     
         7 . A conductive paste for manufacturing a solar cell electrode, comprising, based on the total weight of the conductive paste:
 40 to 90 weight percent of a conductive powder;   5 to 50 weight percent of a solvent; and   3 to 20 weight percent of an amorphous saturated polyester resin with a Tg of 50° C. or lower.