高效多晶硅中石英坩埚内高纯隔离层的致密化处理

Increasing Compactness of High Purity Layer in the Silica Crucible for the Casting of High-performance Multi-crystalline Silicon Ingot

多晶硅铸锭过程中,在石英坩埚内壁制作高纯隔离层可以阻挡石英坩埚中的杂质向硅锭中扩散,改善硅方的边部红区,但高纯隔离层会引起硅锭中氧含量的升高。本文在高纯隔离层的基础上,通过级配的方法提升高纯隔离层结构的致密性并降低硅锭中的氧含量。

In the directional solidification growth of multi-crystalline silicon( mc-Si) ingot,to decrease the proportion of the red-zone near the edge of the ingot,high purity barrier layer was coated onto the inner walls of the silica crucible to prevent the diffusion of impurities from the crucible into the silicon ingot. But the high purity barrier layer can increase the content of oxygen in the silicon ingot. In this paper,the recipe of the high purity barrier layer have been optimized to improve its compactness,and the content of oxygen in the silicon ingot have been decreased.