Control of impurities transport in an industrial directional solidification furnace for silicon ingots basing on computer modeling.

Two kinds of local designs in an industrial directional solidification (DS) furnace were proposed to reduce oxygen (O) and carbon (C) concentrations in multi-crystalline silicon (mc-Si) ingots. Global simulations including coupled oxygen and carbon transport in the furnace were carried out. It was found that the proposed designs have little effect on the oxygen concentration in the silicon melt, while they could significantly influence the CO gas transport in the furnace and the C concentration in the silicon melt. The investigation provides a method to control the carbon impurity in an industrial DS furnace for mc-Si ingots. [ABSTRACT FROM AUTHOR]