NOVELTY - The method comprises subjecting a metallurgical silicon to a thermal process to cause the metallurgical silicon to change in state from a first state to a second state that is a molten state not exceeding 1500 degrees C, where the metallurgical silicon is provided into a crucible apparatus, causing a first portion of impurities to be removed from the metallurgical silicon in the molten state, and cooling the molten metallurgical silicon from a lower region to an upper region to cause the lower region to solidify while a second portion of impurities segregate and accumulate in a liquid state region.    USE - The method is useful for purifying silicon bearing materials for manufacturing a photovoltaic device such as solar cell.    ADVANTAGE - The method is capable of economically, rapidly and safely purifying silicon bearing materials with high silicon purity and without poisonous or dangerous substances thus efficiently manufacturing the solar cell with improved light conversion efficiency.    DETAILED DESCRIPTION - The method comprises subjecting a metallurgical silicon to a thermal process to cause the metallurgical silicon to change in state from a first state to a second state that is a molten state not exceeding 1500 degrees C, where the metallurgical silicon is provided into a crucible apparatus, causing a first portion of impurities to be removed from the metallurgical silicon in the molten state, cooling the molten metallurgical silicon from a lower region to an upper region to cause the lower region to solidify while a second portion of impurities segregate and accumulate in a liquid state region, solidifying the liquid state region to form a resulting silicon structure having a purified region and an impurity region, subjecting an upper molten region of the metallurgical silicon with an inert blanket of gas to prevent external impurities from contacting the metallurgical silicon in the molten state, subjecting a portion of the upper molten region to a hydrogen gas to cause a reaction and to remove a boron impurity with the hydrogen gas to remove the oxygen impurity, subjecting a region of the molten metallurgical silicon to a hydrogen species to remove a boron impurity using a gas. The purified region is characterized by a purity of greater than 99.9999%. The thermal process uses a plasma gun or arc heater (50), has a source of 3000 degrees C, and comprises a thermal pulse or pulses, and a convection process of the molten state. The crucible apparatus remains in a stationary state. The molten metallurgical silicon has a purity of 99% and a temperature profile characterized by a higher temperature region within a center region and a lower temperature region within an edge region of the crucible apparatus. The molten state is free from any foreign objects for circulating the molten metallurgical silicon. The hydrogen species are injected using channel regions. The crucible is maintained in a vacuum to keep the molten metallurgical silicon free from external contaminants. The vacuum is selected to achieve a desired impurity removal characteristic from the molten metallurgical silicon.    DESCRIPTION OF DRAWING(S) - The diagram shows a cross-sectional view of a silicon purifying apparatus.    Vacuum exhaust tube (11)    Crucible (20)    Crucible support (30)    Plasma arc heater (50)    Gas supply tube (60)    Manipulating mechanism (80)    Silicon melt. (100)