Evaluation of the Silicon Ingot With Addition of SiCl $_{\bf 4}$ in Atmosphere During Unidirectional Solidification

Adding SiCl₄ to the atmosphere during the growth of a crystal suppressed crystalline defects and impurities from the edge of silicon ingots. Crystalline silicon ingots with seed crystal were grown by using the unidirectional solidification technique. Most of the grain boundaries were inactive Σ3 in the ingot with the SiCl₄ injection. There were no small-angle grain boundaries at the top and edge of ingots. The carbon concentration with SiCl₄ was decreased to less than half of that without the SiCl₄ injection. Carbon precipitation did not occur even at the surface of ingots and the surface of grown ingots had a metallic luster.