METHOD OF PRODUCTION OF HIGH-PURITY MONOSILANE

摘要

FIELD: production of high-purity monosilane for thin semiconductor and dielectric layers and high-purity poly- and monocrystalline silicon. SUBSTANCE: high-purity monosilane is produced by interaction of metallic silicon with methanol in presence of catalyst at elevated temperature. Methoxysilanes mixed with tetramethoxysilane is separated from reaction products. Methoxysilanes are catalytically disproportioned forming monoxylane at subsequent purification of monoxylane and disproportionation products which are subjected to interaction with methanol. Tetramethoxysilane is separated by rectification and return of active catalytic part for disproportionation. Interaction of liquid disproportionation products with methanol is conducted in film mode at temperature of 30-80 C for at least 10 s. Rectification at separation of tetramethoxysilane is performed in continuous mode at constant level of active catalytic part in still of rectifying column. Cleaning of monosilane from methoxysilane admixtures and other high-boiling compounds is performed by cooling monosilane to temperature below minus 4 C followed by filtration of monosilane from solid methoxysilanes. EFFECT: low cost of process; improved characteristics. 2 cl, 2 ex