PRODUCTION OF POLYCRYSTALLINE SEMICONDUCTOR INGOT AND APPARATUS THEREFOR

PROBLEM TO BE SOLVED: To improve the quality of a polycrystalline semiconductor ingot formed by unidirectional solidification by lessening its distortion. SOLUTION: A silicon semiconductor material 15 is charged into a crucible 1 and inner crucible 2 of a double structure and is heated from above by the radiation heat from a heating element 8 for heating by an induction heating coil 7, by which this material is melted. The bottom of the crucible 1 is placed on a supporting base 4 cooled by the cooling water from a cooling vessel 13. The semiconductor material is melted in the inner crucible 2 and the solidification is started from the bottom. Although the volume of the silicon semiconductor material 15 expands at the time of solidification, a gap is formed between the inner crucible 2 and the crucible 1 and, therefore, if the inner crucible 2 expands outward together with the silicon semiconductor material 15, the distortion at the time of the solidification is lessened and the good polycrystalline semiconductor ingot is obtd.