PRODUCTION OF SILICON SUBSTRATE FOR SOLAR BATTERY

PROBLEM TO BE SOLVED: To provide a method for producing a silicon substrate for a solar battery of high quality, high cell efficiency and a low cost by efficiently removing impurities contained in the metallic silicon starting raw material to the desired concentration level. SOLUTION: The high quality silicon substrate for a solar battery is obtained by melting high purity metallic silicon by an electron beam in vacuum in order to vaporize and remove volatile impurities such as P, Al, Ca or the like, then cutting and removing the condensed part of the heavy metal impurities such as Fe, Ti or the like in a purification process in a solidified phase, further crushing and washing the obtained ingot to obtain a coarsely purified raw material, subsequently plasma-melting the coarsely purified raw material under an oxidizing atmosphere to vaporize and remove non-volatile impurities such as B, C or the like as the oxides, furthermore cutting and removing the condensed part of heavy metal impurities such as Fe, Ti or the like in the solid phase finish purification process and finally slicing the purified ingot.