NOVELTY - A solar cell, comprises: a semiconductor substrate (300); an emitter layer (301) that is formed on the front surface and side surface of the semiconductor substrate; a passivation layer (303) that is formed on the rear surface of the semiconductor substrate; a rear electrode that contacts the semiconductor substrate through the passivation layer; at least one rear field (BSF) layer (304) that is formed in an region where the rear electrode contacts the semiconductor substrate; and a metal electrode (305).    USE - The solar cell is useful for converting solar energy into electrical energy.    ADVANTAGE - The solar cell is cost effective, highly efficient, has excellent light trapping capability, improved contact resistance between metal and silicon, and excellent efficiency while reducing the loss caused by the recombination of electrons and holes. Also, the solar cell has significantly improved photoelectric conversion efficiency by improving the structure of the general solar cell without significantly adding separate processes to the existing processes can be provided with an economical production cost and short production time.    DETAILED DESCRIPTION - A solar cell, comprises: a semiconductor substrate; an emitter layer that is formed on the front surface and side surface of the semiconductor substrate; a passivation layer that is formed on the rear surface of the semiconductor substrate; a rear electrode that contacts the semiconductor substrate through the passivation layer; at least one rear field (BSF) layer that is formed in an region where the rear electrode contacts the semiconductor substrate; and a metal electrode including a finger part that is formed on the front surface of the semiconductor substrate, a penetration part that penetrates through the emitter layer, the semiconductor substrate, and the passivation layer, and a bus bar that is spaced from the rear field layer and is formed on the rear surface of the semiconductor substrate. An INDEPENDENT CLAIM is a fabrication method of a crystalline silicon solar cell, comprising: forming at least one penetration groove that penetrates through the front surface and rear surface of the semiconductor substrate; forming an emitter layer having polarity different from polarity of the semiconductor substrate on the semiconductor substrate; forming a passivation layer with or without at least one contact hole on the rear surface of the semiconductor substrate; forming a metal electrode connected via the penetration groove from the front surface of the semiconductor substrate to the rear surface; and forming a rear electrode that locally contacts the semiconductor substrate and is formed on the rear surface of the semiconductor substrate.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a solar cell.    Semiconductor substrate (300)    Emitter layer (301)    Antireflection film layer (302)    Passivation layer (303)    Localized rear field layer (304)    Metal electrode (305)    Contact holes (310)    Penetration groove (311)