电磁感应定向凝固多晶硅晶粒控制生长与位错运动关联性研究

近年来，高效多晶硅生长技术成为太阳能电池领域的一个研究热点。在该技术路线中如何实现晶粒的控制生长和限制位错的运动是成功的关键。本项目首先研究籽晶颗粒粒度、初始晶粒中晶界和润湿角对凝固初期晶粒结构的影响，阐明同质形核和异质形核在高效多晶硅控制形核中的作用；其次，通过分析凝固过程中晶粒结构和晶界的变化，确定晶粒的取向竞争生长；同时，探讨晶界在取向生长中的作用；最后，将生长过程中典型位错进行重构，分析其形成条件和易出现位错，阐明不同类型晶界对位错运动的作用机制，建立电磁条件下晶粒控制生长与位错运动之间的调控机制，为生产高品质高效多晶硅提供理论指导。

Recently, preparation of High performance multi-crystalline silicon (hp-mc Si) has been attracted more and more attention in the solar cell industry. The key is to achieve successful growth of controlling grains and termination of dislocation movement. In this proposal, the influence of particle size, grain boundary in initial particles and wetting angles on the grain structure during the starting stage of solidification would be investigated, and the function of homogeneous nucleation and heterogeneous nucleation in the control growth of hp-mc Silicon also be illustrated. Then the grain oriented growth mechanism considering the evolution of grain structure and grain boundary will be determined. Moreover, the effect of gain boundary on the grain oriented growth also be analyzed. The development of typical dislocation during solidification will be reconstructed and the formation condition and preferred sites should be analyzed, followed the effect mechanism of grain boundary type on dislocation movement will be explained. Thus, the regulating model of grain controlling growth and dislocation movement might be built, which could provide theoretical basis to prepare the directional solidified multi-crystalline silicon under electro-magnetic induction condition.