Patent ID: 6964876
Filing Date: 2005-11-15
Classification: C23C,C30B

Abstract:
1. A method for depositing crystalline active layers on at least one crystalline substrate from gaseous starting substances, which are introduced, together with a carrier gas, into the process chamber of a reactor, where, depending on process parameters determined in preliminary tests selected from the group consisting of substrate temperature, process chamber pressure, mass flow of the starting substances introduced into the process chamber, total mass flow, and combinations thereof, after prior pyrolytic decomposition, the starting substances are deposited on the substrate and form an active layer having properties selected from the group consisting of stoichiometry, doping, morphology, temperature, growth rate, and combinations thereof determined from surface measurements or measured without contact by sensors acting in the process chamber, characterized in that, in addition to the set of process parameters which contain the process parameters which lead to the desired layer properties, calibration parameters are also determined in the preliminary tests, by the deviations in the layer properties when individual process parameters are varied being determined and the corresponding deviation being placed into a relationship with the process parameter variation, and by, in the production run, prior to the deposition of the active layer, at least one calibration layer, the layer properties of which are measured or determined, being deposited in the same production run, deviation values being formed by placing these properties in a relationship to the desired layer properties, and by one or more process parameters being altered in accordance with the calibration parameters for deposition of the active layer as a function of the magnitude of the deviation values, wherein the method is an MOCVD method.