| 摘要 |
The invention relates to a polycrystalline silicon rod, comprising an outer layer made of polycrystalline silicon having a thickness of 0.01 to 20 mm. Said outer layer contains crystallites having an average size of more than 20 µm. The invention further relates to a method for producing polysilicon by introducing a reaction gas containing a component that contains silicon and containing hydrogen into a reactor, whereby polycrystalline silicon is precipitated in the form of rods, characterized in that a temperature of the rods in a second step of the precipitation is increased by at least 50°C relative to a first step, a concentration of the component containing silicon in the reaction gas being 5 mol% or less and a supply of the component containing silicon being 0.25 mol per 1 m2 of rod surface or less in the second step of the precipitation. The invention further relates to a method for producing polysilicon by introducing a reaction gas containing a component that contains silicon and containing hydrogen into a reactor, whereby polycrystalline silicon is precipitated in the form of rods, characterized in that, after the end of the precipitation, a contamination-free gas flows around the rod-shaped polycrystalline silicon and the rod-shaped polycrystalline silicon is covered with a bag made of plastic and removed from the reactor. |
