工业硅一次定向提纯研究

定向凝固工艺是物理冶金法制备太阳能级多晶硅的一个重要环节。通过控制温度场变化,形成单方向散热趋势,使硅锭定向生长,并利用杂质元素在硅中的分凝特性将金属杂质富集到最后凝固区域,从而达到提纯的目的。本实验采用电磁感应加热后直接拉锭的方法,在真空条件下使熔融的硅逐步脱离感应加热区形成定向凝固的趋势,对工业硅进行提纯。本实验通过对提纯后硅铸锭的杂质分布、组织及电阻率分析,系统评价了定向凝固方法对多晶硅提纯效果。

The Research of Industry Silicon Once Directional Purification

Directional solidification process is an important part that of the physical metallurgy of solar energy polysilicon.By controlling the temperature changes,it forms the trend of a one-way cooling,so that the silicon ingots grows directive,and it uses impurities in silicon segregation characteristics of the metal impurities concentration to the final solidification region.,so as to achieve the purpose of purification.This experiment adopts the direct drawing method after electromagnetic induction heating,in the vacuum so that the gradual melting of silicon formed from the solidification zone induction heating trend,and the industry silicon is purified.In this study,through the impurity distribution,organization and resistivity analysis,it evaluates the directional solidification purification effect on the polysilicon in the round.