Method of fabricating micromechanical components with free-standing microstructures or membranes

摘要

A method is disclosed of fabricating micromechanical components provided with free-standing microstructures or membranes with predetermined mechanical stress, by initially depositing a sacrificial layer on a substrate followed by depositing a polysilicon layer on the sacrificial layer by a gaseous phase deposition and, finally, at least partial removal of the sacrificial layer. During deposition of the polysilicon layer, the process pressure selected determined the type of stress in the polysilicon layer, and the value of the stress is set by the process temperature selected. The process pressure is above the pressure range used in LPCVD reactors.