Thales

Other

Bertrand Leverrier

Claude Rougeot

Bernard Chaumet

Jérôme Inglese

Olivier Lefort

Pierre-Olivier Lefort

Fabien Filhol

Liviu Nicu

Marie-Dominique Bruni-Marchionni

Claude Sarno

Romain Hodot

Régis Quer

Andre Boura

Nicolas Vercier

André Boura

Dominique Leduc

Jérôme Ingelse

A method for calibrating an inertial angular sensor includes: for at least two electrical angles of the vibration wave, applying, via each of the three trim controls, a sinusoidal stiffness disturbance having a disturbance frequency, and for each applied disturbance, determining and storing an estimated excitation force to be applied to the resonator in the presence of the stiffness disturbance, on the basis of excitation controls determined by the servo controls; determining, on the basis of the three estimated excitation forces, three 2×2 matrices, being representative of the response of the gyrometer to the stiffness disturbance; determining and storing an estimated inverse excitation matrix and an estimated inverse detection matrix on the basis of the three matrices, an excitation matrix and a detection matrix being respectively representative of effects of the excitation chain and of effect of the detection chain of the sensor.

Method for calibrating a vibrating inertial sensor

The present invention relates to an electronic system comprising an electronic system comprising an electromechanical microsystem and a hermetic box encapsulating said microsystem. The box includes a fastening plane. The electromechanical microsystem includes a sensitive part and at least two beams connecting the sensitive part to the fastening plane. The beams are thermally coupled to the sensitive part and are electrically coupled to one another. The system further includes a thermal regulator of the electromechanical microsystem including an electrical circuit including at least two ends connected to the beams, and a circuit controller able to generate an electrical current in the electrical circuit to modify the temperature of the sensitive part.

Electronic system comprising a microelectromechanical system and a box encapsulating this microelectromechanical system

A microelectromechanical system comprising an assembly of layers stacked in a stacking direction comprises an active layer made of single-crystal silicon comprising an active structure, and first and second covers defining a cavity around the active structure, the active layer interposed between the first and second covers, the second cover comprising a single layer made of single-crystal silicon. The assembly comprises a decoupling layer made of single-crystal silicon and comprising: an attaching element fastened to a carrier, a frame encircling the attaching element in the plane of the decoupling layer, and a mechanical decoupling structure connecting the frame and the attaching structure, the mechanical decoupling structure allowing the attaching element to be flexibly joined to the frame. The frame is secured to the silicon layer of the second cover and at most one film of silicon dioxide is interposed between the frame and silicon layer of the second cover.

Microelectromechanical system and fabricating process having decoupling structure that includes attaching element for fastening to carrier

A vibrating inertial sensor is provided, micro machined in a plane thin wafer, allowing the measurement of an angular position or of an angular speed. The sensor comprises two vibrating masses suspended by springs with identical stiffness in X and Y and coupled together by identical stiffness springs in X and Y, and at least excitation transducers and detection transducers disposed on at least one of the masses. The mobile assembly consisting of a vibrating mass and the parts of transducers fastened to this mass has a generally symmetric structure with respect to an axis of symmetry OX and with respect to an axis of symmetry OY.

MEMS angular inertial sensor operating in tuning fork mode

The micro-electro-mechanical system is provided with at least two separate anchoring elements (F, F) designed to be bound to a support. A anchoring element (F, F) is solidly linked to at least one beam (P, P) that can be deformed in bending, and two beams (P, P) respectively linked to two distinct anchoring elements (F, F) have different directions. A beam has a length L, a thickness e, and a height h, such that the stiffnesses KL in the directions of the length and of the height Kh are large and the stiffness in the direction of the thickness Ke is small.

Micro-electro-mechanical systems (MEMS)

A gyroscope having a vibrating structure, produced by micromachining in a thin planar wafer, the gyroscope including two symmetrical moving assemblies that are coupled by a coupling structure connecting the two assemblies so as to allow mechanical vibration energy to be transferred between them, each moving assembly including a first moving element connected to the coupling structure and able to vibrate with two degrees of freedom in orthogonal directions Ox and Oy of the plane of the wafer, and a second moving element adjacent the first moving element, capable of vibrating only in the Oy direction and connected to the first moving element via linkage element, wherein the linkage element allow the transmission, in phase opposition, to the second moving element of the vibration movement of the first moving element in the Oy direction.

Micromachined gyroscope with detection in the plane of the machined wafer

Package (BT) for vacuum encapsulation of a microelectromechanical system (MEMS) provided with an electrically conductive element intended to be soldered to said package (BT), said package (BT) comprising a metallized base (FM), designed to be soldered to said microelectromechanical system (MEMS), and output electrical contacts (CES), electrically connected to electrical-contact elements of said microelectromechanical system. Said metallized base (FM) comprises a plurality of metallized surface portions (PSM), respectively bounded by an unmetallized solder stop region, and respectively connected to the rest of the metallized base (FM) by a metallized track (PTEM), having a small width relative to the corresponding width of said portion (PSM), said metallized surface portions (PSM) being designed to be soldered to said microelectromechanical system (MEMS).

Package for vacuum encapsulation of an associated microelectromechanical system, and a method for detecting a problem with a solder joint in such an assembly

The invention relates to a device and a method for detecting a fault in a measurement device comprising a resonator and means for measuring a resonant frequency of the resonator. According to the invention, the device further includes means delivering information (S) representative of the quality factor of the resonator () at the resonant frequency.

Resonator measurement device and method employing the device

The invention relates to a gyrometer based on a vibrating structure, produced by micromachining in a thin planar wafer. It comprises four moving assemblies placed at the vertices of a virtual rectangle, each moving assembly being coupled to two moving assemblies located at neighboring vertices via a coupling structure and comprising an inertial first moving element connected to the coupling structure and intended to vibrate in two orthogonal directions in the plane of the wafer, namely an excitation direction and a detection direction, and a second moving element intended to vibrate in the detection direction and connected, on one side, to the first moving element and, on the other side, to anchoring zones via linking means.

Micromachined double tuning-fork gyrometer with detection in the plane of the machined wafer

The invention relates to a micromachined gyrometer having a planar moving structure anchored on a fixed substrate by anchoring feet, the fixed substrate being mounted on a support substrate via fasteners, the moving structure comprising at least two moving assemblies that are symmetrical with respect to an axis of symmetry A; the anchoring feet are located outside this axis A. The fixed substrate has etched features for the purpose of partly isolating at least one region from the rest of the fixed substrate, this region having a portion of the fixed substrate that includes at least one anchoring foot, and the fixed substrate is mounted on the support substrate via fasteners applied outside the region.

Inertial micromechanical tuning-fork gyrometer

The invention relates to gyroscopes having a vibrating structure that is micromachined in a silicon substrate. A novel vibrating structure is described, which has two moving massesand, connected by a vibration energy coupling structure (transverse arms, longitudinal arms, and a short transverse linkbetween the longitudinal links). The moving masses are also suspended from U-shaped flexure arms (), having one branch end connected to the mass and another end connected to a fixed anchoring point. The flexure arms are not inserted between the coupling structure and the mass, but are independent of the coupling structure. The masses are excited so as to vibrate in their plane by electrostatic forces applied by interdigitated combs. The Coriolis forces make them vibrate perpendicular to the plane, and this vibration is detected by electrodes forming part of the moving masses.

Micromachined inertial sensor for measuring rotational movements

The invention relates to a microgyroscope, that is to say an inertial micromechanical sensor dedicated to the measurement of angular velocities, which is produced by micromachining techniques on a silicon wafer. The gyroscope comprises two symmetrical moving assemblies coupled via a coupling structure. Each of the two assemblies comprises a moving mass surrounded by a moving intermediate frame. The frame is connected to the coupling structure and can vibrate in two degrees of freedom in orthogonal directions Ox and Oy in the plane of the wafer. The mass is connected on one side to the frame and on the other side to fixed anchoring regions via linking means that allow the vibration movement along the Oy direction to be transmitted to the mass without permitting movement of the mass along the Ox direction. An excitation structure is associated with the frame in order to excite its vibration along Ox. A movement detection structure is associated with the mass in order to detect its vibration along Oy.

Micromachined gyroscopic sensor with detection in the plane of the machined wafer

The invention relates to a differential accelerometer micromachined in a plane plate, comprising a base and a differential measurement cell which includes a moveable seismic mass and two force sensors that are connected to the mass and to the base. Under the effect of an acceleration along Ox and/or Oy, Ox and Oy being directions orthogonal to the plane of the plate, the seismic mass is capable of undergoing linear displacement along a direction parallel to the acceleration, and has a center of gravity located at the intersection of a plane Aperpendicular to the plane of the plate and passing through Ox and of a plane Aperpendicular to the plane of the plate and passing through Oy; a first force sensor comprises, along Ox, two identical detection systems for a differential measurement of the linear displacement along Ox, and associated with each detection system a filtering system connected to the base, and a second force sensor comprises, along Oy, two other identical detection systems for the differential measurement of the linear displacement along Oy, and associated with each detection system a filtering system connected to the base, each filtering system allowing the associated detection system to move along a direction perpendicular to that of its detection without permitting it to move along its detection direction.

Multiaxial micromachined differential accelerometer

An active part of a sensor is formed, for example, by micro-machined silicon wafers bearing electronic elements, electrical conductors, connection pads, and pins. The pads are electrically connected to the pin ends by conductive elements. Then the wafer and the pin ends are plunged into an electrolytic bath to make an electrolytic deposit of conductive metal on the pin ends, the pads, and the conductive elements that connect them. Finally, this metal is oxidized or nitrized to form an insulating coat on the pin ends, the pads, and the conductive elements that connect them. Such a sensor may find particular application as a sensor designed to work in harsh environments.

Micromachined sensor with insulating protection of connections

A sensor of physical quantities, such as a pressure sensor or an acceleration sensor, and more specifically to the mounting of the active part of the sensor on a base bearing connection pins. An active part of the sensor includes, for example, micro-machined silicon wafers bearing electronic elements, electrical conductors, and connection pads. A base is also prepared, provided with pins whose upper ends are spatially arranged, with each pin facing a respective connection pad. The face bearing the connection pads is applied to the upper part of the pins, and the unit is dipped into an electrolytic bath to deposit metal that rigidly solders the pins to the connection pads. Preferably, the conductive parts, pins, and connection pads of the unit are then covered with an insulator to prevent electrical leakage between pins subjected to different potentials.

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Montelier, France

Bertrand Leverrier