METHODS FOR PREPARING A MELT OF SILICON POWDER FOR SILICON CRYSTAL GROWTH

摘要

Methods for preparing a melt from silicon powder for use in growing a single crystal or polycrystalline silicon ingot in accordance with the Czochralski method that include removal of silicon oxides from the powder; application of a vacuum to remove air and other oxidizing gases; controlling the position of the charge relative to the heater during and after melting of the powder and maintaining the charge above its melting temperature for a period of time to allow oxides to dissolve; and use of a removable spacer between the crucible sidewall and the silicon powder charge to reduce oxides and silicon bridging.