POLYCRYSTALLINE SILICON INGOT, PROCESS FOR PRODUCING SAME, AND USES THEREOF

摘要

A process for producing a polycrystalline silicon ingot by unidirectionally solidifying molten silicon in a crucible upward from the bottom of the crucible, wherein the molten silicon is unidirectionally solidified under such conditions that when the temperature measured at a position in the vicinity of the center of the undersurface of the crucible falls from (Tm-20)°C to (Tm-60)°C, where Tm is the temperature measured at the position when the silicon temperature is the melting point of the silicon, then there is a period during which that temperature falls at a rate of 1-10 °C/hr, thereby obtaining the polycrystalline silicon ingot.