Cvd reactor having a substrate holder resting on a gas cushion comprising a plurality of zones

Abstract

The invention relates to a CVD reactor having a process chamber () and a substrate holder support () arranged therein, said support comprising at least one bearing surface (), wherein a plurality of gas inlet lines () open out into the bearing surface ('). The CVD reactor further has a substrate holder (), the back side thereof facing the bearing surface (′), wherein the gases fed through the gas inlet lines () into the space between the bearing surface (′) and back side form a gas cushion () supporting the substrate holder (). According to the invention, the gas cushion comprises a plurality of zones (A, C) that each can be fed through an associated gas inlet line () and that are separated from each other by a means () preventing gas exchange between the zones (A, C). At least one inner zone (C) is associated with a gas discharge line (), via which the gas fed into the inner zone (C) by way of the inlet line () can be discharged. Gases having different heat conduction properties are fed into the zones.