| 摘要 |
The present invention provides a process for preparing a polycrystalline silicon having the surface layer in which the areas having a short carrier lifetime due to Fe has been substantially eliminated. A preparation method of polycrystalline silicon comprising preparing a mold evenly applied with a mold release agent produced by mixing a binder and a solvent with a silicon nitride powder and then solidifying a molten silicon in said mold, wherein x≰5.0, 20≰y≰100 and x�y≰100 are satisfied given that x represents a concentration of Fe (atomic ppm) contained as impurity in the silicon nitride powder and y represents a thickness of the mold release agent (μm) applied to the mold. |
