An object of the present invention is to provide, at a low cost, a system and a method for manufacturing a solar cell having high conversion efficiency. A solar cell according to the present invention is characterized by including a passivation film that protects a semiconductor substrate, a first finger electrode connected to the semiconductor substrate on a main surface of the semiconductor substrate, a first bus bar electrode that intersects the first finger electrode, and an intermediate layer provided in an intersecting position of the first finger electrode and the first bus bar electrode . The solar cell is characterized in that the first finger electrode and the first bus bar electrode are electrically connected to each other via the intermediate layer.

Provided in one embodiment is a method of making paste for solar cells. The method can include forcing silver through a feed tube coupled to a hydrodynamic cavitation chamber using an air-driven piston. The method can include subjecting the silver to hydrodynamic cavitation in the hydrodynamic cavitation chamber by using a hydraulic pump to pass the silver sequentially through a primary orifice, a secondary orifice, and a final orifice within the hydrodynamic cavitation chamber to produce the paste for the solar cells. The silver can include up to three unique silver powders having a total particle size distribution from 0.1 microns to 10 microns. A first silver powder can have a first average particle size of 1.5 um, a second silver powder having a second average particle size of 0.5 um, and a third silver powder having a third average particle size of 0.2 um.

Provided in one embodiment is a method of making paste for solar cells. The method can include forcing silver through a feed tube coupled to a hydrodynamic cavitation chamber using an air-driven piston. The method can include subjecting the silver to hydrodynamic cavitation in the hydrodynamic cavitation chamber by using a hydraulic pump to pass the silver sequentially through a primary orifice, a secondary orifice, and a final orifice within the hydrodynamic cavitation chamber to produce the paste for the solar cells. The silver can include up to three unique silver powders having a total particle size distribution from 0.1 microns to 10 microns. A first silver powder can have a first average particle size of 1.5 um, a second silver powder having a second average particle size of 0.5 um, and a third silver powder having a third average particle size of 0.2 um.

Provided is a conductive ink including a conductive material and at least one benzoxazine-based compound. The conductive ink of the present invention can be easily formed into a thin film, is highly conductive after sintering, and has superior adhesion to various substrates. In addition, the use of the conductive ink according to the present invention facilitates the formation of a glossy, mirror-like metal thin film with high reflectance.

Provided is a conductive ink including a conductive material and at least one benzoxazine-based compound. The conductive ink of the present invention can be easily formed into a thin film, is highly conductive after sintering, and has superior adhesion to various substrates. In addition, the use of the conductive ink according to the present invention facilitates the formation of a glossy, mirror-like metal thin film with high reflectance.

Articles containing a matrix material and plurality of copper nanoparticles in the matrix material that have been at least partially fused together are described. The copper nanoparticles are less than about 20 nm in size. Copper nanoparticles of this size become fused together at temperatures and pressures that are much lower than that of bulk copper. In general, the fusion temperatures decrease with increasing applied pressure and lowering of the size of the copper nanoparticles. The size of the copper nanoparticles can be varied by adjusting reaction conditions including, for example, surfactant systems, addition rates, and temperatures. Copper nanoparticles that have been at least partially fused together can form a thermally conductive percolation pathway in the matrix material.

Articles containing a matrix material and plurality of copper nanoparticles in the matrix material that have been at least partially fused together are described. The copper nanoparticles are less than about 20 nm in size. Copper nanoparticles of this size become fused together at temperatures and pressures that are much lower than that of bulk copper. In general, the fusion temperatures decrease with increasing applied pressure and lowering of the size of the copper nanoparticles. The size of the copper nanoparticles can be varied by adjusting reaction conditions including, for example, surfactant systems, addition rates, and temperatures. Copper nanoparticles that have been at least partially fused together can form a thermally conductive percolation pathway in the matrix material.

The invention provides an electroconductive paste comprising 50-90 wt. % of copper particle, 0.5-10 wt. % of a glass frit, 0.1-5% wt. % of adhesion promoter, which is at least one selected member from the group consisting of cuprous oxide, titanium oxide, zirconium oxide, boron resinate, zirconium resinate, amorphous boron, lithium phosphate, bismuth oxide, aluminum oxide, and zinc oxide, and 5-20 wt. % of an organic vehicle. An article comprising an aluminum nitride substrate and electroconductive paste of the invention is also provided. A method of forming an electroconductive circuit comprising is also provided.

The invention provides an electroconductive paste comprising 50-90 wt. % of copper particle, 0.5-10 wt. % of a glass frit, 0.1-5% wt. % of adhesion promoter, which is at least one selected member from the group consisting of cuprous oxide, titanium oxide, zirconium oxide, boron resinate, zirconium resinate, amorphous boron, lithium phosphate, bismuth oxide, aluminum oxide, and zinc oxide, and 5-20 wt. % of an organic vehicle. An article comprising an aluminum nitride substrate and electroconductive paste of the invention is also provided. A method of forming an electroconductive circuit comprising is also provided.

The present invention relates to an inorganic reaction system used in the manufacture of electroconductive pastes. The inorganic reaction system comprises a lead containing matrix forming composition and a tellurium oxide additive. Preferably the lead containing matrix forming composition is between 5-95 wt. % of the inorganic reaction system, and the tellurium oxide additive is between 5-95 wt. % of the inorganic reaction system. The lead containing matrix forming composition may be a glass frit, and may comprise lead oxide. Another aspect of the present invention relates to an electroconductive paste composition that comprises metallic particles, an inorganic reaction system as previously disclosed, and an organic vehicle. Another aspect of the present invention relates to an organic vehicle that comprises one or more of a binder, a surfactant, a solvent, and a thixatropic agent. Another aspect of the present invention relates to a solar cell printed with an electroconductive paste composition as disclosed, as well as an assembled solar cell module. Another aspect of the present invention relates to a method of producing a solar cell.