Method for making an electromechanical component on a plane substrate and comprising at least one structure vibrating in the plane of the substrate and actuation electrodes. The method comprises at least the following steps in sequence: formation of the substrate comprising one silicon area partly covered by two insulating areas, formation of a sacrificial silicon and germanium alloy layer by selective epitaxy starting from the uncovered part of the silicon area, formation of a strongly doped silicon layer by epitaxy, comprising a monocrystalline area arranged on said sacrificial layer and two polycrystalline areas arranged on insulating areas, simultaneous formation of the vibrating structure and actuation electrodes, by etching of a predetermined pattern in the monocrystalline area designed to form spaces between the electrodes and the vibrating structure, elimination of said sacrificial silicon and germanium alloy layer by selective etching.