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Indexed by:期刊论文

Date of Publication:2017-08-15

Journal:MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING

Included Journals:SCIE、EI、Scopus

Volume:67

Page Number:1-7

ISSN No.:1369-8001

Key Words:Directional solidification; Grain morphology; Interstitial impurity; Substitutional impurity

Abstract:A multicrystalline silicon ingot with columnar and irregular grains was obtained from metallurgical-grade silicon (MG-Si) by directional solidification. The segregation behaviors of substitutional and interstitial impurities in different grain morphologies have been studied. The concentration distribution of substitutional impurities (B and Al) in the silicon ingot was accord with the Scheil's equation, which depended on the grain morphology. However, the concentration distribution of interstitial impurities (Fe, Ti, Cu, and Ni) was only accord with the Scheil's equation under the columnar grains growth condition. The difference lattice sites of the impurities will result in the disparate segregation behavior of impurities for columnar and irregular grains growth, which leads to the diverse concentration distribution of substitutional and interstitial impurities in the silicon ingot. Furthermore, the transport mechanism of interstitial and substitutional impurities in front of the solid-liquid interface boundary has been revealed.