HIGH-PURITY MONOSILANE PRODUCTION PROCESS Russian patent published in 2006 - IPC C01B33/04 

FIELD: organosilicon materials.

SUBSTANCE: invention relates to a process for production of high-purity monosilane suitable to form thin-film semiconductor products as well as high-purity poly- and monocrystalline silicon for a variety of applications (semiconductor engineering, solar power engineering). Process is accomplished as follows. Trialkoxysilane is prepared by etherification of hydrogen bond-containing chlorosilanes by an alcohol or via direct reaction of alcohol with powdered commercial silicon in presence of catalyst. Trialkoxysilane is preliminarily purified to remove alcohol and other undesirable impurities and the routed to catalytic disproportionation to produce monosilane. 1-2% solution of potassium tert-butylate in tetraalkoxysilane is used as catalyst. Solution of catalyst and that of trialkoxysilane are taken at ratio 1:(10÷20) with pH from neutral to weakly alkaline and passed into lower part of reactor in continuous mode at normal temperature and pressure. Gaseous monosilane with vapors of organic and organoelemental impurities is then subjected to absorption treatment followed by removal trace impurities via adsorption on activated carbon, chemisorption, and condensation of high-purity monosilane.

EFFECT: reduced trialkoxysilane disproportionation time, increased trialkoxysilane conversion, enhanced efficiency of removal of impurities from monosilane, and universalized monosilane sorption treatment system.

2 tbl, 7 ex