Methods for depositing thick layers of GaN, in particular, onto silicon or sapphire.

Abstract

This invention relates to a method for depositing a layer (13) on a substrate (12), wherein the material of the layer (13) has a different coefficient of thermal expansion and / or lattice constant than that of the substrate (12), wherein the substrate (12) is heated to a higher temperature in a process chamber (6) of a CVD reactor (1), and at this higher temperature, process gas supplied by a gas mixing system (18) is introduced into the process chamber (6) through a gas inlet member (2), wherein the process gas decomposes into decomposition products in the process chamber (6) or on the surface of the substrate (12), and these decomposition products form the layer (13), wherein the substrate (12) has a middle section (7) and a radially outer edge section (8). To reduce the bending of the substrate (12), the edge section (8) is heated to a temperature higher than that of the middle section (7). This invention also relates to a CVD reactor having a heating device having an external heating zone (10) for heating the edge section (8) to a higher temperature.

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