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

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