Laser firing apparatus for high efficiency solar cell and fabrication method thereof

Abstract

Disclosed are a laser firing apparatus for a high efficiency solar cell including laser generating unit and a fabrication method thereof. The laser firing apparatus for a high efficiency solar cell includes at least one laser generating unit that irradiates a laser irradiation on to an electrode region formed on a semiconductor substrate for the solar cell and heat-treats the electrode region. In addition, the fabrication method of a solar cell includes forming an electrode material on a semiconductor substrate for the solar cell; and forming an electrode by heat treating the electrode material by laser irradiation.

1 . A laser firing apparatus for a solar cell, comprising:
 at least one laser generating unit that irradiates a laser irradiation on to an electrode region formed on a semiconductor substrate for the solar cell and heat-treats the electrode region.   
     
     
         2 . The laser firing apparatus for the solar cell according to  claim 1 , wherein the laser irradiation is in a line form. 
     
     
         3 . The laser firing apparatus for the solar cell according to  claim 1 , wherein the laser irradiation is in a line form, and the line form is formed by a slit. 
     
     
         4 . The laser firing apparatus for the solar cell according to  claim 1 , wherein the at least one laser generating unit further comprises a plurality of laser generating units disposed on a line. 
     
     
         5 . The laser firing apparatus for the solar cell according to  claim 1 , wherein the at least one laser generating unit includes a first laser generating unit that is positioned to irradiate a front surface of the semiconductor substrate and a second laser generating unit that is positioned to irradiate a back surface of the semiconductor substrate and the first laser generating unit and the second laser generating unit are disposed to oppose each other. 
     
     
         6 . The laser firing apparatus for the solar cell according to  claim 1 , wherein the at least one laser generating unit includes a first laser generating unit a the second laser generating unit that are positioned to irradiate one surface of the semiconductor substrate and are disposed to be parallel with each other. 
     
     
         7 . The laser firing apparatus for the solar cell according to  claim 1 , further comprising a stage used to seat the semiconductor substrate. 
     
     
         8 . The laser firing apparatus for the solar cell according to  claim 7 , wherein the stage is at least one belt type moving unit that moves the semiconductor substrate. 
     
     
         9 . The laser firing apparatus for the solar cell according to  claim 8 , wherein the at least one belt type moving unit includes a first belt type moving unit and a second belt type moving unit. 
     
     
         10 . A fabrication method of a solar cell, comprising:
 forming an electrode material on a semiconductor substrate for the solar cell; and   forming an electrode by heat treating the electrode material by laser irradiation;   wherein the electrode material comprising electrode paste, electrode ink and aerosol for electrode.   
     
     
         11 . The fabrication method of the solar cell according to  claim 10 , wherein the electrode material is formed according to a front electrode pattern and is formed on the front surface of the semiconductor substrate. 
     
     
         12 . The fabrication method of the solar cell according to  claim 11 , wherein the material for the front electrode is heat-treated at a temperature of 600° C. to 1000° C. by the laser irradiation. 
     
     
         13 . The fabrication method of the solar cell according to  claim 10 , wherein the electrode material is formed according a back electrode pattern and is formed on the back surface of the semiconductor substrate. 
     
     
         14 . The fabrication method of the solar cell according to  claim 13 , wherein the material for the back electrode formed according to the back electrode pattern is heat-treated at a temperature of 450° C. to 750° C. by the laser irradiation. 
     
     
         15 . The fabrication method of the solar cell according to  claim 13 , wherein the material for the back electrode formed on the back surface of the semiconductor substrate is formed into the back electrode by heat treatment, and a back surface field (BSF) layer is formed at an interface between the back surface and back electrode of the semiconductor substrate. 
     
     
         16 . The fabrication method of the solar cell according to  claim 11 , wherein the material for the front electrode and the material for the back electrode are simultaneously fired by simultaneous laser irradiations. 
     
     
         17 . The fabrication method of the solar cell according to  claim 13 , wherein the material for the front electrode and the material for the back electrode are simultaneously fired by simultaneous laser irradiations. 
     
     
         18 . The fabrication method of the solar cell according to  claim 10 , wherein the semiconductor substrate is heat-treated by laser irradiations. 
     
     
         19 . The fabrication method of the solar cell according to  claim 10 , wherein the semiconductor substrate is a p type impurity semiconductor substrate or an n type impurity semiconductor substrate. 
     
     
         20 . The fabrication method of the solar cell according to  claim 10 , further comprising forming an antireflective layer on a front surface of the semiconductor substrate prior to forming the electrode material. 
     
     
         21 . The fabrication method of the solar cell according to  claim 10 , further comprising forming a back passivation layer on the back surface of the semiconductor substrate prior to forming the electrode material.