G01P2015/0837

Physical quantity sensor, sensor device, electronic apparatus, and moving object
10352701 · 2019-07-16 · ·

A physical quantity sensor includes a base substrate, a movable portion that is oscillatably provided around an axis while facing the base substrate and that is divided into a first movable portion and a second movable portion, a first fixed electrode that is disposed on the base substrate facing the first movable portion, and a second fixed electrode that is disposed on the base substrate facing the second movable portion. The first fixed electrode and the second fixed electrode are configured so as to offset at least a part of a difference between a first fringe capacitance, which is between the first movable portion and the first fixed electrode, and a second fringe capacitance, which is between the second movable portion and the second fixed electrode.

Accelerometer sensor system

Embodiments of the invention include an accelerometer system. The system includes an accelerometer sensor comprising first and second electrode configurations and an inertial mass between the first and second electrode configurations. In one example, the accelerometer sensor being fabricated as symmetrically arranged about each of three orthogonal mid-planes. The system also includes an accelerometer controller configured to apply control signals to each of the first and second electrode configurations to provide respective forces to maintain the inertial mass at a null position between the first and second electrode configurations. The accelerometer controller can measure a first pickoff signal and a second pickoff signal associated with the respective first and second electrode configurations. The first and second pickoff signals can be indicative of a displacement of the inertial mass relative to the null position. The accelerometer controller can calculate an acceleration based on the first and second pickoff signals.

SINGLE AXIS INERTIAL SENSOR WITH SUPPRESSED PARASITIC MODES
20190187169 · 2019-06-20 ·

A single axis inertial sensor includes a proof mass spaced apart from a surface of a substrate. The proof mass has first, second, third, and fourth sections. The third section diagonally opposes the first section relative to a center point of the proof mass and the fourth section diagonally opposes the second section relative to the center point. A first mass of the first and third sections is greater than a second mass of the second and fourth sections. A first lever structure is connected to the first and second sections, a second lever structure is connected to the second and third sections, a third lever structure is connected to the third and fourth sections, and a fourth lever structure is connected to the fourth and first sections. The lever structures enable translational motion of the proof mass in response to Z-axis linear acceleration forces imposed on the sensor.

Micromechanical sensor and method for producing a micromechanical sensor

A micromechanical sensor that is produced surface-micromechanically includes at least one mass element formed in a third functional layer that is non-perforated at least in certain portions. The sensor has a gap underneath the mass element that is formed by removal of a second functional layer and at least one oxide layer. The removal of the at least one oxide layer takes place by introducing a gaseous etching medium into a defined number of etching channels arranged substantially parallel to one another. The etching channels are configured to be connected to a vertical access channel in the third functional layer.

LOW-POWER ACCELEROMETER
20190128918 · 2019-05-02 ·

The invention relates to an accelerometer comprising a plurality of proof-masses (M1-M4) moveable along a measurement axis (AB); a respective spring (K1-K4) rigidly attached to each proof-mass, configured to exert an elastic recall on the proof-mass in the measurement axis; a fixed stop (S1-S4) associated with each proof-mass, arranged to intercept the proof-mass when the acceleration in the measurement axis increases by a step; and an electrical contact associated with each stop, configured to be closed when the associated proof-mass reaches the stop. The proof-masses are suspended in series with respect to one another by springs in the measurement axis, the stops being arranged to successively intercept the respective proof-masses for increasing thresholds of acceleration.

MEMS SENSOR WITH DUAL PENDULOUS PROOF MASSES
20190100426 · 2019-04-04 · ·

A MEMS sensor is disclosed that includes dual pendulous proof masses comprised of sections of different thickness to allow simultaneous suppression of vertical and lateral thermal gradient-induced offsets in a MEMS sensor while still allowing for the normal operation of the accelerometer. In an embodiment, the structure and different sections of the MEMS sensor is realized using multiple polysilicon layers. In other embodiments, the structure and different thickness sections may be realized with other materials and processes. For example, plating, etching, or silicon-on-nothing (SON) processing.

MICROMECHANICAL SENSOR SYSTEM

A micromechanical sensor system that includes a mass that is deflectable at least in the z direction. A stop element having an elastic design is situated on the mass on at least one of the sides oriented in the z direction, via a connection element.

MEMS piston-tube based capacitive accelerometer
10241129 · 2019-03-26 ·

A novel high resolution, low noise MEMS capacitive accelerometer is disclosed. The accelerometer utilizes a piston-tube electrode configuration that enables the use of a wide area for the electrodes. Therefore, a high capacitive sensitivity is achieved. The accelerometer consists of two structures: upper and lower. The lower structure contains a plurality of fixed electrodes that are attached to the base and have a piston-style shape (teeth). Those pistons form the sensing electrodes of the accelerometer. The upper structure contains a plurality of moving electrodes that have a tube-style shape (through holes), and they are attached to a substrate via restoring mechanical springs. The proof mass of the accelerometer is distributed around these tubes to reduce squeeze thin film damping in the system. The accelerometer is able to sense linear acceleration along the z-axis and/or the angular acceleration about the in-plane axes (x and y).

Z-axis microelectromechanical detection structure with reduced drifts
10209269 · 2019-02-19 · ·

Described herein is a microelectromechanical detection structure, provided with: a substrate having a top surface extending in a plane; a detection-electrode arrangement; an inertial mass, suspended above the substrate and the detection-electrode arrangement; and elastic elements, coupling the inertial mass to a central anchorage element fixed with respect to the substrate, in such a way that it is free to rotate about an axis of rotation as a function of a quantity to be detected along a vertical axis, the central anchorage element being arranged at the axis of rotation. A suspension structure is coupled to the detection-electrode arrangement for supporting it, suspended above the substrate and underneath the inertial mass, and is anchored to the substrate via at least one first anchorage region; the fixed-electrode arrangement is anchored to the suspension structure via at least one second anchorage region.

ELECTROSTATIC OFFSET CORRECTION

A MEMS sensor has a proof mass, a sense electrode, and a shield. At least a portion of the proof mass and shield may form a capacitor that causes an offset movement of the proof mass. A series of test values may be provided in order to minimize the offset movement or compensate for the offset movement. In some embodiments, the shield voltage may be modified to reduce the offset movement. Residual offsets due to other factors may also be determined and utilized for compensation to reduce an offset error in a sensed signal.