Process for the chemical vapour deposition of a thin film of oxide on a silicon wafer.

摘要

A process for depositing silicon dioxide on silicon wafers at low pressure from tetraethoxysilane includes a step of introducing a constant flow of nitrogen into a vacuum pump (18) in parallel with exhaust flows from a deposition tube (16) containing the silicon wafers. Tetraethoxysilane is vapourised and flowed into the deposition tube (16) containing the silicon wafers. Tetraethoxysilane is vapourised and flowed into the deposition tube (16) where is pyrolyzes on the silicon wafers to deposit silicon dioxide thereon. Product gases and unexpended tetraethoxysilane are drawn out of the deposition tube (16) by the vacuum pump (18). The constant flow of nitrogen provides a ballast effect to regulate the flow of tetraethoxysilane.