Element migration behavior at the front of solid-liquid interface, as the key link in the stable migration between multi-phase, has a decisive influence on purification. In this work, by studying the influence of interface stability on the impurity migration process, the bow out grain boundaries caused by interface instability was considered to be an important factor affecting the stable separation of impurities. Even based on overall stable migration, local inter-granular instability caused by component super-cooling would still reduce the overall removal effect of impurities. A method is urgently needed to improve the stability of element migration at the front of the interface, so as to obtain silicon materials with high purity or uniformity. Direct current, as an external means, was introduced to optimize the local temperature gradient at the front of the S/L interface. Based on the characteristics of the sharp rise of resistivity in the solidification stage of silicon, the joule heat was used to form a local heat source at the S/L interface, so as to realize the temperature regulation in the micro region. On the premise of maintaining a relatively higher temperature gradient inside the melt, reduced the temperature gradient at the S/L interface, so as to optimize the grain growth and suppress the occurrence of component super-cooling.

Instability of inter-granular structure and direct current regulation technology

Where thousands of chemistry professionals meet to share ideas and advance scientific and technical knowledge. Spring 2023 abstracts, posters, and presentations will launch at the end of March.

ACS Spring 2023

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.