Abstract: A method of producing a semiconductor device using a selective epitaxial growth (SEG) process is disclosed. In one aspect, the method comprises providing a semiconductor substrate, forming a pattern of an insulation material on the semiconductor substrate, thereby defining a covered and non covered surface, performing a cleaning processing of the covered and non covered surface of the substrate having the insulating pattern defined, loading the substrate with the insulating pattern into a reaction chamber of an epitaxial reactor, and starting a selective epitaxial growth comprising an injection of at least one semiconductor source gas possibly with at least one first carrier gas in the reaction chamber of the epitaxial reactor. The method further comprises, prior to the selective epitaxial growth, the surface of the substrate is subjected in the reaction chamber to an in situ pre-treatment with the injection of a halogen containing etching gas possibly with a second carrier gas.