Method and apparatus for the continuous vapor deposition of silicon on substrates

A process for the continuous vapor deposition of silicon on substrates, comprising the following steps:

• (a) introducing at least one substrate into a reaction chamber;
• (b) introducing a process gas and also at least one gaseous silicon precursor compound into the reaction chamber;
• (c) forming a gaseous mixture of at least one silicon-based intermediate in coexistence with the gaseous silicon precursor compound and the process gas in the reaction chamber;
• (d) forming a silicon layer by vapor deposition of silicon from at least one of the gaseous silicon precursor compound or from the silicon-based intermediate on the substrate;
• (e) discharging an excess of the gaseous mixture from the reaction chamber into a circulation conduit;
• and
• (f) recirculating at least one constituent of the excess of the gaseous mixture selected from at least one of the silicon precursor compound, the silicon-based intermediate, or the process gas through the circulation conduit and into the reaction chamber;
• wherein regulation and introduction of the gaseous silicon precursor compound from the circulation conduit and into the reaction chamber is controlled such that a molar ratio of the silicon-based intermediate to the silicon precursor compound has a value of from 0.2:0.8 to 0.5:0.5, and the corresponding molar ratio of the silicon-based intermediate product to the silicon precursor compound is adjusted within a gas stream flowing from the circulation conduit into the reaction chamber.