PROCESS FOR PREPARING SYNTHETIC QUARTZ ARTICLES Russian patent published in 1996 - IPC

FIELD: semiconductor industry. SUBSTANCE: process comprises spraying silicon dioxide formed from decomposition from volatile silicon compound in oxygen-hydrogen plasma flow onto heat-resistant molder and subsequently vitrifying the sprayed half-finished article in vacuum. Spraying of half-finished quartz articles (crucibles) is carried out onto molder made of semiconductor purity silicon using silicon monosilane as volatile compound, the monosilane to oxygen molar ratio being 1:(10-30) at 1373-1573 K. Hydrogen is fed along slit passage at hydrogen to oxygen molar ratio of 1:(0.3-0.5). Monosilane is recovered by low-temperature rectification from gas-vapor mixture intended for obtaining high-ohmic silicon, and is used without further purification. The process makes it possible to improve quality of crucibles due to lower content of impurities by about an order, increase recovery of silicon dioxide from the raw product and eliminate outbursts of chlorine-containing compounds into environment. EFFECT: more efficient preparation process. 3 cl