Method for simultaneously producing electronic-grade dichIorosilane, electronic-grade trichlorosilane and electronic-grade silicon tetrachloride

Abstract

The invention relates to a method for simultaneously producing electronic-grade dichIorosilane, electronic-grade trichlorosilane and electronic-grade silicon tetrachloride. The method uses crude trichlorosilane as a raw material; and the method comprises the steps of first-stage dust removal, gas phase adsorption, first-stage light-component removal, first-stage heavy-component removal, disproportionation, addition of a complexing agent, second-stage dust removal, first-stage separation, second-stage separation treatment, second-stage light-component removal treatment, second-stage heavy-component removal treatment, third-stage separation treatment, third-stage light-component removal, third-stage heavy-component removal, fourth-stage light-component removal, and fourth-stage heavy-component removal. According to the method provided by the invention, the process route is based on a current process route of preparing electronic-grade dichIorosilane, steps are changed and adjusted, so that a requirement of purity of raw material trichlorosilane is reduced, and the electronic-grade dichIorosilane, the electronic-grade trichlorosilane and the electronic-grade silicon tetrachloride canbe simultaneously obtained; and the products have a less content of impurities such as metal impurities, chlorosilane impurities and boron impurities, and stable quality, and can meet the requirementsof large-scale integrated circuits.

Description

technical field [0001] The invention relates to a method for simultaneously producing electronic-grade dichlorodihydrosilane, electronic-grade trichlorosilane and electronic-grade silicon tetrachloride, belonging to the technical field of chlorosilane production. Background technique [0002] Electronic-grade dichlorodihydrogen silicon, electronic-grade trichloro-silicon and electronic-grade silicon tetrachloride are mainly used for silicon epitaxial growth and silicon sources for large-scale integrated circuits. At present, electronic-grade dichlorodihydrosilane and trichlorosilane are mainly monopolized by international giants such as Japan. With the rapid development of my country's semiconductor industry and the demand for localization of semiconductor materials and equipment, it has broken the foreign demand for electronic-grade dichlorodihydrosilane and trichlorosilane. The monopoly of electronic grade trichlorosilane in my country ensures the healthy development of my ...

AI Technical Summary

Problems solved by technology

[0003] At present, there is no electronic-grade dichlorodihydrogen silicon that can really reach the semiconductor level in the domestic market, and the process route is either purified from dichlorodihydrogen silicon, a by-product of polysilicon, or made from trichlorosilane as a raw material. However, the requirements for raw materials are very high, some require more than 4N, and some require at least 3N. The requirements are extremely high, and the above-mentioned impurity control of domestic electronic grade dichlorosilane is unstable; moreover, the dichlorodihydrogen silicon that is thrown out of the high boiling or low boiling matter in the preparation process of dichlorodihydrogen silicon is extremely difficult to handle. The industry urgently needs to be able to use low-quality trichlorosilane as raw material, to be able to stably control product metal impurities, boron phosphorus impurities and other chlorosilane impurities, and to be able to handle the process of dichlorodihydrosilane discharged during the preparation process

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