Abstract: The invention provides a method of fabricating an electromechanical structure presenting a first substrate including a layer of monocrystalline material covered in a sacrificial layer that presents a free surface, the structure presenting a mechanical reinforcing pillar in the sacrificial layer, the method including etching a well region in the sacrificial layer to define a mechanical pillar; depositing a first functionalization layer of the first material to at least partially fill the well region and cover the free surface of the sacrificial layer around the well region; depositing a second material different from the first material for terminating the filling of the well region to thereby cover the first functionalization layer around the well region, planarizing the filler layer, the pillar being formed by the superposition of the first material and second material in the well region; and releasing the electromechanical structure by removing at least partially the sacrificial layer.

Abstract: An HBAR resonator comprises, on a substrate, a piezoelectric transducer, said transducer comprising at least one piezoelectric layer, at least two series of electrodes and exhibiting resonance frequencies Fi corresponding to wavelengths ?i, characterized in that it comprises an amplification structure comprising at least one resonant cavity arranged on the substrate between said transducer and said substrate or in said substrate, this amplification structure being suitable for mechanically resonating at least one of the resonance frequencies Fi of said transducer corresponding to said wavelength ?i, so as to amplify the amplitude of the electrical resonance generated at said frequency.

Abstract: An electromechanical device having a resonator using acoustic waves propagating laterally within a piezoelectric plane resonant structure and electrodes on a face of said structure. The resonant structure comprises: a transduction region having a transduction length and generating acoustic waves; a free propagation region for the acoustic waves, adjacent to the transduction region and defined the plane of the transduction region; the resonant structure length being equal to an integer number of half-wavelengths, the resonance frequency of said resonator equaling the average propagation velocity of the wave within the structure divided by said wavelength, to adjust the quality factor of the resonator fixed by the length of the resonant structure and the coupling coefficient fixed by the ratio of the transduction length over the length of the resonant structure; the resonant structure defined by the assembly of the transduction region and the propagation region being laterally bounded by reflection regions.

Abstract: A micro or nano electromechanical transducer device formed on a semiconductor substrate comprises a movable structure which is arranged to be movable in response to actuation of an actuating structure. The movable structure comprises a mechanical structure having at least one mechanical layer having a first thermal response characteristic, at least one layer of the actuating structure having a second thermal response characteristic different to the first thermal response characteristic, and a thermal compensation structure having at least one thermal compensation layer. The thermal compensation layer is different to the at least one layer and is arranged to compensate a thermal effect produced by the mechanical layer and the at least one layer of the actuating structure such that the movement of the movable structure is substantially independent of variations in temperature.

Abstract: The invention provides a method of fabricating an electromechanical structure presenting a first substrate including a layer of monocrystalline material covered in a sacrificial layer that presents a free surface, the structure presenting a mechanical reinforcing pillar in the sacrificial layer, the method including etching a well region in the sacrificial layer to define a mechanical pillar; depositing a first functionalization layer of the first material to at least partially fill the well region and cover the free surface of the sacrificial layer around the well region; depositing a second material different from the first material for terminating the filling of the well region to thereby cover the first functionalization layer around the well region, planarizing the filler layer, the pillar being formed by the superposition of the first material and second material in the well region; and releasing the electromechanical structure by removing at least partially the sacrificial layer.

Abstract: An HBAR resonator comprises, on a substrate, a piezoelectric transducer, said transducer comprising at least one piezoelectric layer, at least two series of electrodes and exhibiting resonance frequencies Fi corresponding to wavelengths ?i, characterized in that it comprises an amplification structure comprising at least one resonant cavity arranged on the substrate between said transducer and said substrate or in said substrate, this amplification structure being suitable for mechanically resonating at least one of the resonance frequencies Fi of said transducer corresponding to said wavelength ?i, so as to amplify the amplitude of the electrical resonance generated at said frequency.

Abstract: A method of forming an electromechanical transducer device comprises forming on a fixed structure a movable structure and an actuating structure of the electromechanical transducer device, wherein the movable structure is arranged in operation of the electromechanical transducer device to be movable in relation to the fixed structure in response to actuation of the actuating structure. The method further comprises providing a stress trimming layer on at least part of the movable structure, after providing the stress trimming layer, releasing the movable structure from the fixed structure to provide a released electromechanical transducer device, and after releasing the movable structure changing stress in the stress trimming layer of the released electromechanical transducer device such that the movable structure is deflected a predetermined amount relative to the fixed structure when the electromechanical transducer device is in an off state.

Abstract: A micro or nano electromechanical transducer device formed on a semiconductor substrate comprises a movable structure which is arranged to be movable in response to actuation of an actuating structure. The movable structure comprises a mechanical structure comprising at least one mechanical layer having a first thermal response characteristic and a first mechanical stress response characteristic, at least one layer of the actuating structure, the at least one layer having a second thermal response characteristic different to the first thermal response characteristic and a second mechanical stress response characteristic different to the first mechanical stress response characteristic, a first compensation layer having a third thermal response characteristic and a third mechanical stress characteristic, and a second compensation layer having a fourth thermal response characteristic and a fourth mechanical stress response characteristic.

Abstract: An electromechanical device having a resonator using acoustic waves propagating laterally within a piezoelectric plane resonant structure and electrodes on a face of said structure. The resonant structure comprises: a transduction region having a transduction length and generating acoustic waves; a free propagation region for the acoustic waves, adjacent to the transduction region and defined the plane of the transduction region; the resonant structure length being equal to an integer number of half-wavelengths, the resonance frequency of said resonator equaling the average propagation velocity of the wave within the structure divided by said wavelength, to adjust the quality factor of the resonator fixed by the length of the resonant structure and the coupling coefficient fixed by the ratio of the transduction length over the length of the resonant structure; the resonant structure defined by the assembly of the transduction region and the propagation region being laterally bounded by reflection regions.

Abstract: A process for closure of at least one cavity intended to encapsulate or be part of a microelectronic device, comprising the following steps: a) Producing a cavity in a first substrate comprising a first layer traversed by an opening forming an access to the cavity; b) Producing a portion of bond material around the opening, on a surface of the first layer located on the side opposite the cavity; c) Producing, on a second substrate, a portion of fusible material, with a deposition of the fusible material on the second substrate and the use of a mask; d) Placing the portion of fusible material in contact with the portion of bond material; e) Forming a plug for the opening, which adheres to the portion of bond material, by melting and then solidification of the fusible material; f) Separating the plug and the second substrate.

Abstract: A method of forming an electromechanical transducer device comprises forming on a fixed structure a movable structure and an actuating structure of the electromechanical transducer device, wherein the movable structure is arranged in operation of the electromechanical transducer device to be movable in relation to the fixed structure in response to actuation of the actuating structure. The method further comprises providing a stress trimming layer on at least part of the movable structure, after providing the stress trimming layer, releasing the movable structure from the fixed structure to provide a released electromechanical transducer device, and after releasing the movable structure changing stress in the stress trimming layer of the released electromechanical transducer device such that the movable structure is deflected a predetermined amount relative to the fixed structure when the electromechanical transducer device is in an off state.

Abstract: The invention relates to a method of fabricating an electromechanical device including an active element, wherein the method comprises the following steps: a) making a monocrystalline first stop layer on a monocrystalline layer of a first substrate; b) growing a monocrystalline mechanical layer epitaxially on said first stop layer out of at least one material that is different from that of the stop layer; c) making a sacrificial layer on said active layer out of a material that is suitable for being etched selectively relative to said mechanical layer; d) making a bonding layer on the sacrificial layer; e) bonding a second substrate on the bonding layer; and f) eliminating the first substrate and the stop layer to reveal the surface of the mechanical layer opposite from the sacrificial layer, the active element being made by at least a portion of the mechanical layer.

Abstract: A micro or nano electromechanical transducer device formed on a semiconductor substrate comprises a movable structure which is arranged to be movable in response to actuation of an actuating structure. The movable structure comprises a mechanical structure comprising at least one mechanical layer having a first thermal response characteristic and a first mechanical stress response characteristic, at least one layer of the actuating structure, the at least one layer having a second thermal response characteristic different to the first thermal response characteristic and a second mechanical stress response characteristic different to the first mechanical stress response characteristic, a first compensation layer having a third thermal response characteristic and a third mechanical stress characteristic, and a second compensation layer having a fourth thermal response characteristic and a fourth mechanical stress response characteristic.

Abstract: A micro or nano electromechanical transducer device formed on a semiconductor substrate comprises a movable structure which is arranged to be movable in response to actuation of an actuating structure. The movable structure comprises a mechanical structure having at least one mechanical layer having a first thermal response characteristic, at least one layer of the actuating structure having a second thermal response characteristic different to the first thermal response characteristic, and a thermal compensation structure having at least one thermal compensation layer. The thermal compensation layer is different to the at least one layer and is arranged to compensate a thermal effect produced by the mechanical layer and the at least one layer of the actuating structure such that the movement of the movable structure is substantially independent of variations in temperature.

Abstract: The invention relates to a piezoelectric actuation structure including at least one strain gauge and at least one actuator produced from a stack on the surface of a substrate of at least one layer of piezoelectric material arranged between a bottom electrode layer and a top electrode layer, at least a portion of the stack forming the actuator being arranged above a cavity produced in the substrate, characterized in that the strain gauge is a piezoresistive gauge located in the top electrode layer and/or the bottom electrode layer, the layer or layers including electrode discontinuities making it possible to produce said piezoresistive gauge. The invention also relates to a method for producing such a structure.

Abstract: The invention relates to a method of making a component from a heterogeneous substrate comprising first and second portions in at least one monocrystalline material, and a sacrificial layer constituted by at least one stack of at least one layer of monocrystalline Si situated between two layers of monocrystalline SiGe, the stack being disposed between said first and second portions of monocrystalline material, wherein the method consists in etching said stack by making: e) at least one opening in the first and/or second portion and the first and/or second layer of SiGe so as to reach the layer of Si; and f) eliminating all or part of the layer of Si.

Abstract: The invention relates to a piezoelectric actuation structure including at least one strain gauge and at least one actuator produced from a stack on the surface of a substrate of at least one layer of piezoelectric material arranged between a bottom electrode layer and a top electrode layer, at least a portion of the stack forming the actuator being arranged above a cavity produced in the substrate, characterized in that the strain gauge is a piezoresistive gauge located in the top electrode layer and/or the bottom electrode layer, the layer or layers including electrode discontinuities making it possible to produce said piezoresistive gauge. The invention also relates to a method for producing such a structure.

Abstract: The invention provides a method of fabricating and electromechanical device having an active element on at least one substrate, the method having the steps of: a) making a heterogeneous substrate having a first portion, an interface layer, and a second portion, the first portion including one or more buried zones sandwiched between first and second regions formed in a first monocrystalline material, the first region extending to the surface of the first portion, and the second region extending to the interface layer, at least one said buried zone being made at least in part out of a second monocrystalline material so as to make it selectively attackable relative to the first and second regions; b) making openings from the surface of the first portion and through the first region, which openings open out to at least one said buried zone; and c) etching at least part of at least one buried zone to form at least one cavity so as to define at least one active element that is at least a portion of the second regio

Abstract: A process for closure of at least one cavity intended to encapsulate or be part of a microelectronic device, comprising the following steps: a) Producing a cavity in a first substrate comprising a first layer traversed by an opening forming an access to the cavity; b) Producing a portion of bond material around the opening, on a surface of the first layer located on the side opposite the cavity; c) Producing, on a second substrate, a portion of fusible material, with a deposition of the fusible material on the second substrate and the use of a mask; d) Placing the portion of fusible material in contact with the portion of bond material; e) Forming a plug for the opening, which adheres to the portion of bond material, by melting and then solidification of the fusible material; f) Separating the plug and the second substrate.

Abstract: A device for recognizing an individual, including a sensor including a plurality of sensitive members having a contact area on which a portion likely to be that of the individual to be recognized is applied, a measurement mechanism connected to the sensitive members to supply information on local contact forces generated by the portion applied on the contact area, and a processor connected to the sensor to determine from the local contact forces a morphological characteristic of the individual to be recognized. The measurement mechanism also supplies information relating to at least another physical magnitude related to the contact, and the processor determines from the other physical magnitude a physiological characteristic of the individual to be recognized.