Distribution of light-element impurities in Si crystals grown by seed-casting method

Abstract

We investigated the distributions of interstitial oxygen (O i ) and substitutional carbon (C s ) in high-performance (HP) multicrystalline Si (mc-Si) and monocrystalline-like Si (mono-like Si) and compared them with those in conventional mc-Si, grown using the same furnace. The O i concentration in mono-like Si grown using a Czochralski (Cz) silicon seed was the highest among the three crystals. On the other hand, the O i and C s concentrations in HP mc-Si grown using Siemens Si incubation seeds were the same as those in conventional mc-Si. Therefore, it is considered that O i incorporated into the growing Si crystal originates not only from the quartz crucible wall but also from the seed. Additionally, O i and C s in HP mc-Si grown on the incubation seeds with adequately low O i and C s concentrations are distributed similarly to those in conventional mc-Si grown under the same conditions. We believe that it is important to consider the O i and C s concentrations in the feed stock materials both for the seed and whole ingots in the seed-casting method.