Indexed by:Journal Article

Date of Publication:2017-11-01

Journal:VACUUM

Included Journals:EI、SCIE、Scopus

Volume:145

Page Number:251-257

ISSN:0042-207X

Key Words:Silicon; Directional solidification; Distribution of impurity; Fluctuant growth rate

Abstract:A theoretical model to determine distribution of iron impurity during silicon purification by directional solidification with fluctuant crystal growth rate is proposed in this paper. The crystal growth rate is fluctuant usually and it has profound effect on the distribution of iron impurity in practical production. The model validation by the distribution of iron impurity during silicon purification by directional solidification in industrial production and the results show that the calculation agrees with existing experimental results. The results also indicate that distribution of iron impurity is directly correlated with the instantaneous value of crystal growth rate. The high fluctuant distribution of iron impurity during silicon purification by directional solidification can be well explained. Many potential applications of the model in practical production are found, such as predicting the distribution of iron impurity with fluctuant crystal growth rate, evaluating the effect degree of production accident, design and optimization of the process parameters and evaluating of maximum yield for raw silicon with different impurity concentration. Silicon purification with low energy consumption is possible based on the research in this paper. (C) 2017 Elsevier Ltd. All rights reserved.