Purification of monosilane

Abstract

Abstract PURPOSE:To obtain high-purity monosilane, by reducing a monosilane prepared by the reduction of SiCl4, treating it at low temperature, treating it with active carbon, treating it with synthetic zeolite having specific pore diameters so that impurities are removed efficiently. CONSTITUTION:A monosilane (SiH4) gas containing impurities obtained by reducing SiCl4 with diethylaluminum hydride (AlEt2H) is treated as follows. Namely, the monosilane gas is brought into contact with a reducing agent (e.g., AlEt2H) and reduced and cooled to at <=-20 deg.C. The reduction temperature is usually -10-60 deg.C, especially 0-40 deg.C. The monosilane gas after cooling treatment is treated with active carbon, and monochlorosilane is preferentially adsorbed. The monosilane gas containing the remaining impurities is passed through a column packed with synthetic zeolite having pore diameters of 4-4.5Angstrom so that the remaining impurities are eliminated, to give high-purity SiH4. The temperature of the treatment is preferably -20--75 deg.C.

Inventors

• 👤 Tetsuya Iwao
• 👤 岩尾　徹也
• 👤 Osamu Kido
• 👤 木戸　修
• 👤 Yoshiaki Toyoda
• 👤 豊田　芳昭
• 👤 Reiji Hirai
• 👤 平井　礼治
• 👤 Yoshinori Ashida
• 👤 芦田　芳徳

Bibliographic Details