Method of manufacturing a finger electrode for a solar cell
A method of manufacturing a finger electrode for a solar cell including printing a conductive paste on one surface of a substrate using a print mask having an aperture ratio of about 65% or more, and baking the printed conductive paste. The conductive paste includes a conductive powder, a glass frit, and an organic vehicle. The organic vehicle includes a solvent having a vapor pressure of about 0.1 Pa to about 500 Pa at room temperature and a flash point of about 90° C. to about 150° C.
1. A method of manufacturing a finger electrode for a solar cell, the method comprising:
printing a conductive paste on one surface of a substrate using a print mask having an aperture ratio of about 65% or more; and
baking the printed conductive paste;
wherein:
the print mask includes:
a mesh including weft threads and warp threads;
a photosensitive resin layer integrated with the mesh; and
an electrode printing portion from which the photosensitive resin layer is removed, wherein an interval of weft threads of the mesh on upper and lower portions of the electrode printing portion is wider than the interval of weft threads on remaining portions of the mesh,
the conductive paste includes a conductive powder, a glass frit, and an organic vehicle, the organic vehicle including a solvent having a vapor pressure of about 0.1 Pa to about 500 Pa at room temperature and a flash point of about 90° C. to about 150° C.
2. The method as claimed in claim 1 , wherein the print mask has an aperture ratio of about 65% to about 90%.
3. The method as claimed as claimed in claim 1 , wherein the baking is performed at a temperature of about 700° C. to about 1,000° C.
4. The method as claimed in claim 1 , wherein the solvent includes at least one selected from dipropylene glycol n-propyl ether, dipropylene glycol n-butyl ether, tripropylene glycol methyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, dipropylene glycol phenyl ether, diethylene glycol methyl ether, triethylene glycol methyl ether, diethylene glycol ethyl ether, triethylene glycol ethyl ether, diethylene glycol n-butyl ether, triethylene glycol n-butyl ether, diethylene glycol n-butyl ether acetate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, ethylene glycol hexyl ether, diethylene glycol hexyl ether, ethylene glycol phenyl ether, diethylene glycol phenyl ether, trimethylnonanol, and diethylene glycol dibutyl ether.
5. The method as claimed as claimed in claim 1 , wherein the conductive paste includes:
about 60 wt % to about 95 wt % of the conductive particles;
about 0.5 wt % to about 20 wt % of the glass frit; and
about 1 wt % to about 30 wt % of the organic vehicle.
6. The method as claimed as claimed in claim 5 , wherein the conductive paste further includes at least one additive selected from a dispersing agent, a thixotropic agent, a plasticizer, a viscosity stabilizer, an antifoaming agent, a pigment, an ultraviolet stabilizer, an antioxidant, and a coupling agent.
7. The method as claimed in claim 1 , wherein the finger electrode satisfies the following Formula 1:
0.4≤ A≤ 0.6 [Formula 1]
wherein, A is an aspect ratio represented by the following formula: thickness of the finger electrode/width of the finger electrode.