Solar cell and solar cell module

A method for manufacturing a solar cell comprising a semiconductor substrate having at least a pn junction formed therein, an antireflection coating layer on a light-receiving surface of the semiconductor substrate, a multiplicity of finger electrodes for current collection which are formed in comb shape on the light-receiving surface of the semiconductor substrate and bonded to the semiconductor substrate, a plurality of bus bar electrodes for collecting current from the finger electrodes which extend orthogonal to the longitudinal direction of the finger electrodes and are connected to the finger electrodes, and rear electrodes on a rear surface of the semiconductor substrate, comprising rear bus bar electrodes for current collection on the rear side without finger electrodes, the rear bus bar electrodes extending the same direction as the longitudinal direction of the bus bar electrodes on the light-receiving surface,

• wherein the semiconductor substrate is of silicon and has a thickness of less than 500 μm,
• first finger electrodes which are joined and connected to a first bus bar electrode are spaced apart from second finger electrodes which are joined and connected to a second bus bar electrode extending parallel with the first bus bar electrode,
• the first and second finger electrodes project from the first and second bus bar electrodes to which they are joined and connected, respectively, in opposite directions orthogonal to the first and second bus bar electrodes, and
• at each of the opposite ends of the first and second finger electrodes projecting from the bus bar electrodes, an auxiliary electrode is joined and connected to longitudinal ends of all adjacent finger electrodes whereby longitudinal ends of all adjacent finger electrodes are electrically connected together by the auxiliary electrode:
• the method comprising forming the antireflection coating layer on the light-receiving surface of the semiconductor substrate, screen printing a rear electrode pattern comprising the rear bus bar electrodes without finger electrodes with a rear surface conductive paste containing silver powder, glass frit, organic vehicle and organic solvent on a rear surface of the semiconductor substrate, screen printing by using a screen printing plate having an electrode pattern of the bus bar electrodes, the finger electrodes, and the auxiliary electrodes on the antireflection coating layer with a light-receiving side conductive paste containing silver powder, glass frit, organic vehicle and organic solvent, drying the rear surface conductive paste on the rear surface of the semiconductor substrate and the light-receiving side conductive paste on the light-receiving surface side of the semiconductor substrate, and firing the printed rear surface conductive paste and the printed light-receiving side conductive paste at the firing-through temperature of the light-receiving side conductive paste to form the rear bus bar electrodes without finger electrodes, the bus bar electrodes, the finger electrodes and the auxiliary electrodes of silver sintered body, wherein the finger electrodes and the auxiliary electrodes are bonded to the semiconductor substrate, each finger electrode of the multiplicity of finger electrodes has a width of 30 to 120 μm, and the auxiliary electrodes have a width of 60 to 360 μm.