NOVELTY - Metallic silicon is provided into silicon-melting container in vacuum chamber. Then, the metallic silicon is subjected to plasma exposure process to remove boron by oxidation, or electron-beam irradiation process to remove phosphorus. The plasma exposure process is carried out by irradiating plasma gas on metallic silicon in atmosphere containing oxygen, and heating. The electron-beam irradiation process is carried out by irradiating electron beam on metallic silicon in atmosphere having high-vacuum degree, and heating. Thus, purification of silicon is carried out.    USE - Method for purifying silicon used for components of semiconductor device and solar cell.    ADVANTAGE - The method efficiently and economically provides silicon having high purity, in high yield using reduced amount of heat energy.    DETAILED DESCRIPTION - Metallic silicon is provided into silicon-melting container in vacuum chamber. Then, the metallic silicon is subjected to plasma exposure process to remove boron by oxidation, or electron-beam irradiation process to remove phosphorus. The plasma exposure process is carried out by irradiating plasma gas containing inert gas, on metallic silicon in atmosphere containing oxygen and having low-vacuum degree, and heating. The electron-beam irradiation process is carried out by irradiating electron beam on metallic silicon in atmosphere having high-vacuum degree, and heating. When silicon is maintained at molten state in silicon-melting container, the vacuum chamber is switched to vacuum atmosphere for performing remaining electron-beam irradiation process or plasma exposure process. Thus, purification of silicon is carried out. An INDEPENDENT CLAIM is included for apparatus for purifying silicon, which has vacuum chamber, silicon-melting container, plasma irradiation apparatus (16), electron-beam irradiation apparatus (15), and switching unit which switches vacuum chamber to vacuum atmosphere.    DESCRIPTION OF DRAWING(S) - The drawing shows schematic view of apparatus for purifying silicon. (Drawing includes non-English language text)    Electron-beam irradiation apparatus (15)    Plasma irradiation apparatus (16)    Silicon-holding container (20)    Heater (21)    Gas supply control apparatus (31)