针对硅中硼难去除的问题，从熔渣结构层面进行研究，通过观察熔渣不同部位在不同电场条件下熔渣结构的变化，分析不同电场条件下高温骤冷所得熔渣结构变化，探索引入电场对熔渣结构影响。结果表明，引入电场会引起熔渣中离子定向移动与重新分配，改变熔渣结构。熔渣上部结构在电场作用下解聚更彻底，远离渣金界面处熔渣结构变化较小。电场增强有利于熔渣解聚，电场强度达10 V时，熔渣中结构单元会转变为聚合度更低的Q0结构单元。熔渣上部结构对电场变化更敏感，电场改变，熔渣下部结构变化较小。
To development the photovoltaic industry for high-quality, high-end, the high-quality silicon raw materials are urgently required. Since boron (B) has a large separation coefficient and a small saturated vapor in the silicon, it is difficult to remove by directional solidification and vacuum melting or the like. B in silicon is one of the most difficult impurities to remove, slag refining is a mean to effectively remove B from silicon materials. In the slag refining process, the introduction of electric field can significantly improve the refining effect. The refining effect is closely related to the slag structure. In view of the difficult problem of removing B from silicon, this work studied on the structural level. The influence of electrical field on the structure was studied by observing the changes of different part of the slag structure and the high temperature quenching slag structural under different electric field conditions. It was found that the introduction of electric field caused the directional movement and redistribution of ions in slag, which caused the change of the slag structure. The upper structure of the slag was more completely depolymerized under the action of the electric field, but the slag structure was basically unchanged in the part which was from the interface of the slag. The electric field enhancement was beneficial to the depolymerization of the slag and when the electric field strength reached 10 V, the relative amount of Q0 structural unit with more non-bridge oxygen (NBO) increased. The upper structure of the slag was more sensitive to the change of the electric field. But the change of structure in the lower part of the slag was not obvious when the electric field changed.
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