Solar cell panel manufacturing method and paste for solar cell electrode used therefor
In a method for manufacturing a solar cell panel according to an embodiment of the present invention, a step of forming an electrode comprises the steps of: forming a main electrode part on a conductive region; and forming a connection electrode part on the main electrode part by using a paste comprising metal particles having a first metal, a solder material having a second metal different from the first metal, and an adhesive material.
1. A method for manufacturing a solar cell panel, the method comprising:
forming a semiconductor substrate and a photoelectric conversion unit including a conductivity type region positioned at the semiconductor substrate or on the semiconductor substrate;
forming an electrode comprising:
forming a main electrode portion on the conductivity type region; and
forming a connection electrode portion on the main electrode portion comprising:
applying a paste, including a first metal particles, a solder material including a second metal different from the first metal, and an adhesive material, to the main electrode portion; and
performing a heat treatment on the paste at a high temperature to mix the first metal powder and the second metal;
attaching a wiring portion electrically connected to the electrode on the electrode; and
laminating the solar cell and the wiring portion, a sealing member surrounding the solar cell and the wiring portion, a first cover member positioned on the sealing member and on one surface of the solar cell, and a second cover member positioned on the sealing member and on other surface of the solar cell.
2. The method of claim 1 , wherein the metal particles include copper particles, copper particles coated with an organic material, or copper particles coated with a metal different from copper,
wherein the second metal includes tin, and
wherein the adhesive material includes a non-conductive organic material or a non-conductive inorganic material.
3. The method of claim 2 , wherein the solder material includes a tin-silver-copper (Sn—Ag—Cu, SAC)-based alloy, and
wherein the adhesive material consists of a flux including carbon, oxide, and rosin.
4. The method of claim 1 , wherein when a total volume of the metal particles, the solder material, and the adhesive material is 100, a volume ratio of the adhesive material is 30 to 70.
5. The method of claim 1 , wherein when a total volume of the metal particles and the solder material is 100, a volume ratio of the metal particles is 15 to 80, and a volume ratio of the solder material is 20 to 85.
6. The method of claim 1 , wherein forming the connection electrode portion comprises:
connecting a plurality of metal particles including the first metal to form a particle connection layer;
aggregating the second metal at an outer surface of the particle connection layer to form a cover layer covering at least the outer surface of the particle connection layer; and
forming the connection electrode portion including the particle connection layer and the cover layer.
7. The method of claim 1 , further comprising:
between the forming of the main electrode portion and the forming of the connection electrode portion, forming an insulating member in an overlap portion in which the electrode and a wiring member do not need to be electrically connected.
8. The method of claim 1 , further comprising:
between the forming of the photoelectric conversion unit and the forming of the electrode, forming an insulating member in an overlap portion in which the electrode and a wiring member do not need to be electrically connected.
9. The method of claim 1 , wherein the heat treatment is performed by a reflow process performed at a temperature of 180° C. to 280° C.