Method for cleaning bell jar, method for manufacturing polycrystalline silicon and device for drying bell jar

摘要

A bell jar comprises a metallic bell jar (1) and a metallic base plate (2) for placing the bell jar (1) thereon, wherein a packing (3) seals the inside of the container. The base plate (2) is connected with a pressure gauge (4), a gas introduction line (5) and a gas discharge line (6), thereby enabling the monitoring of the inner pressure of the bell jar (1) and introduction and discharge of gas. A vacuum pump (7) is provided on the path of the gas discharge line (6) and reduces the inner pressure of the bell jar such that it is lower than the vapor pressure of water. The vacuum pump (7) reduces the inner pressure of the bell jar such that it is lower than the vapor pressure of water and thereby water is removed effectively and drying of the bell jar is finished in a short time. Thus, a technique contributing to the manufacture of high purity polycrystalline silicon by increasing the cleanliness of the bell jar inner surface is provided.