Abstract: 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.

Abstract: The variable capacitance (1) according to the invention is based on a novel principle: a dielectric fluid (20) is placed in the air gap constituted by two capacitor electrodes (12, 14), the fluid being able to be displaced in a direction and outside the cavity (10) formed between said two electrodes (12, 14). Advantageously, the dielectric fluid (20) is displaced according to the principle of communicating vessels, with the presence of a second cavity (30) in fluidic relation with the first cavity. Actuation electrodes (46, 48) in the second cavity (30) induce the deflection of a membrane (44) in order to modify the relative heights of fluidic liquid in the two cavities (10, 30).

Abstract: A MOS transistor with a deformable gate formed in a semiconductor substrate, including source and drain areas separated by a channel area extending in a first direction from the source to the drain and in a second direction perpendicular to the first one, a conductive gate beam placed at least above the channel area extending in the second direction between bearing points placed on the substrate on each side of the channel area, and such that the surface of the channel area is hollow and has a shape similar to that of the gate beam when said beam is in maximum deflection towards the channel area.

Abstract: A method for forming a variable capacitor including a conductive strip covering the inside of a cavity, and a flexible conductive membrane placed above the cavity, the cavity being formed according to the steps of: forming a recess in the substrate; placing a malleable material in the recess; having a stamp bear against the substrate at the level of the recess to give the upper part of the malleable material a desired shape; hardening the malleable material; and removing the stamp.

Abstract: A microelectromechanical system comprises a beam and an electrode coupled to the beam via electrostatic interaction. The beam is designed to undergo elastic flexural deformation and has an approximately constant cross section. The beam consists of several flat faces that extend over the length of the beam, each having a thickness of less than an external dimension of the cross section. A flexural vibration frequency of the beam is then increased compared with a solid beam of the same external dimensions. Such a microelectromechanical system is suitable for applications requiring very short transition times, or for producing high-frequency oscillators and resonators.

Abstract: A first electrode is integral to a beam having two ends securedly affixed to a support fixed onto a substrate. Residual stresses cause buckling of the beam so that the arch of the beam is close to at least one second electrode. The support can be formed by a ring fixed to the substrate by means of two fixing bases arranged on each side of the ring on a fixing axis passing through the centre of the ring, the beam being arranged on a diameter of the ring perpendicular to the fixing axis. The ring comprises at least one layer tensile stressed along the fixing axis. The beam can comprise at least one layer stressed in compression along a longitudinal axis of the beam. The second electrode can be integral to an additional support, the beam being arranged between the substrate and the second electrode.

Abstract: A variable capacitor having a groove portion formed in an insulating substrate, two upper portions of the substrate located on either side of the groove portion forming two lateral edges, a conductive layer covering the inside of the groove portion, a flexible conductive membrane, placed above the groove portion by bearing on the edges, a dielectric layer covering the conductive layer or the membrane to insulate the conductive layer and the membrane, and terminals of application of a voltage between the conductive layer and the membrane, and such that the depth of the groove portion continuously increases from one of the edges to the bottom of the groove portion, and that the conductive layer covers the inside of the groove portion at least to reach one of the two edges, that it may cover.

Abstract: A variable capacitor having a groove portion formed in an insulating substrate, two upper portions of the substrate located on either side of the groove portion forming two lateral edges, a conductive layer covering the inside of the groove portion, a flexible conductive membrane, placed above the groove portion by bearing on the edges, a dielectric layer covering the conductive layer or the membrane to insulate the conductive layer and the membrane, and terminals of application of a voltage between the conductive layer and the membrane, and such that the depth of the groove portion continuously increases from one of the edges to the bottom of the groove portion, and that the conductive layer covers the inside of the groove portion at least to reach one of the two edges, that it may cover.

Abstract: A variable capacitor having a groove portion formed in an insulating substrate, two upper portions of the substrate located on either side of the groove portion forming two lateral edges, a conductive layer covering the inside of the groove portion, a flexible conductive membrane, placed above the groove portion by bearing on the edges, a dielectric layer covering the conductive layer or the membrane to insulate the conductive layer and the membrane, and terminals of application of a voltage between the conductive layer and the membrane, and such that the depth of the groove portion continuously increases from one of the edges to the bottom of the groove portion, and that the conductive layer covers the inside of the groove portion at least to reach one of the two edges, that it may cover.

Abstract: A MOS transistor with a deformable gate formed in a semiconductor substrate, including source and drain areas separated by a channel area extending in a first direction from the source to the drain and in a second direction perpendicular to the first one, a conductive gate beam placed at least above the channel area extending in the second direction between bearing points placed on the substrate on each side of the channel area, and such that the surface of the channel area is hollow and has a shape similar to that of the gate beam when said beam is in maximum deflection towards the channel area.