Invensense, Inc.

Matthew Julian Thompson

Joseph Seeger

Sarah Nitzan

Houri Johari-Galle

Vadim M Tsinker

Kirt Williams

Ilya Gurin

Leonardo Baldasarre

David deKoninck

Varun Subramaniam Kumar

Jongwoo Shin

Logeeswaran Veerayah Jayaraman

Le Jin

Luca Coronato

Sriraman Dakshinamurthy

Stephen Lloyd

Giacomo Laghi

Roberto Martini

Michael J Dueweke

Alexander Castro

Jin Qiu

Ali Shirvani

Antonio Molfese

Mrigank Sharma

Robert Walmsley

A MEMS sensor may include multiple sense electrodes located relative to respective portions of one or more proof masses of a MEMS layer of the sensor. Individual sense electrodes are capable of individual calibration within the drive and/or sense path for the sense electrode. A distance between each individual sense electrode relative to a proof mass is determined for the at-rest state of the sensor. Calibration values are determined based on these distances, and individual drive and/or sense signals associated with each sense electrode are modified to adjust for changes in distance, such as are caused by shifting, tilting, or bending of the MEMS layer or substrate.

MEMS strain sensitivity calibration

A microelectromechanical system device is described. The microelectromechanical system device can comprise: a proof mass coupled to an anchor via a spring, wherein the proof mass moves in response to an imposition of an external load to the proof mass, and an overtravel stop comprising a first portion and a second portion.

Low stress overtravel stop

A MEMS sensor includes a central anchoring region that maintains the relative position of an attached proof mass relative to sense electrodes in the presence of undesired forces and stresses. The central anchoring region includes one or more first anchors that rigidly couple to a cover substrate and a base substrate. One or more second anchors are rigidly coupled to only the cover substrate and are connected to the one or more first anchors within the MEMS layer via an isolation spring. The proof mass in turn is connected to the one or more second anchors via one or more compliant springs.

MEMS design with shear force rejection for reduced offset

An exemplary microelectromechanical device includes a MEMS layer, portions of which respond to an external force in order to measure the external force. A substrate layer is located below the MEMS layer and an anchor couples the substrate layer and MEMS layer to each other. A plurality of temperature sensors are located within the substrate layer to identify a temperature gradient being experienced by the MEMS device. Compensation is performed or operations of the MEMS device are modified based on temperature gradient.

Systems and methods for operating a mems device based on sensed temperature gradients

Systems and methods for operating a MEMS device based on sensed temperature gradients

A MEMS accelerometer includes a suspended spring-mass system that has a frequency response to accelerations experienced over a range of frequencies. The components of the suspended spring-mass system such as the proof masses respond to acceleration in a substantially uniform manner at frequencies that fall within a designed bandwidth for the MEMS accelerometer. Digital compensation circuitry compensates for motion of the proof masses outside of the designed bandwidth, such that the functional bandwidth of the MEMS accelerometer is significantly greater than the designed bandwidth.

High performance accelerometer

A MEMS sensor includes a proof mass that is suspended over a substrate. A sense electrode is located on a top surface of the substrate parallel to the proof mass, and forms a capacitor with the proof mass. The sense electrodes have a plurality of slots that provide improved performance for the MEMS sensor. A measured value sensed by the MEMS sensor is determined based on the movement of the proof mass relative to the slotted sense electrode.

Electrode layer partitioning

A method of measuring noise of an accelerometer can comprise exposing the accelerometer comprising a micro-electro-mechanical system (MEMS) component coupled to an application specific integrated circuit component (ASIC), to an external environmental input, with the MEMS component being configured to provide a first output to the ASIC based on the external environmental input. The method can further comprise estimating a first noise generated by operation of the MEMS component, and replacing the first output provided to the ASIC from the MEMS component, with a second output generated by a MEMS emulator component, with the second output comprising the first noise. Further, the method can include generating an output of the accelerometer based on the second output processed by the ASIC.

Measuring a noise level of an accelerometer

Exemplary embodiment of a tilting z-axis, out-of-plane sensing MEMS accelerometers and associated structures and configurations are described. Disclosed embodiments facilitate improved offset stabilization. Non-limiting embodiments provide exemplary MEMS structures and apparatuses characterized by one or more of having a sensing MEMS structure that is symmetric about the axis orthogonal to the springs or flexible coupling axis, a spring or flexible coupling axis that is aligned to one of the symmetry axes of the electrodes pattern, a different number of reference electrodes and sense electrodes, a reference MEMS structure having at least two symmetry axes, one which is along the axis of the springs or flexible coupling, and/or a reference structure below the spring or flexible coupling axis.

MEMS structure for offset minimization of out-of-plane sensing accelerometers

A microelectromechanical (MEMS) device may be coupled to a dielectric material at an upper planar surface or lower planar surface of the MEMS device. One or more temperature sensors may be attached to the dielectric material layer. Signals from the one or more temperature sensors may be used to determine a thermal gradient along on axis that is normal to the upper planar surface and the lower planar surface. The thermal gradient may be used to compensate for values measured by the MEMS device.

Package level thermal gradient sensing

Facilitating self-calibration of a sensor device via modification of a sensitivity of the sensor device is presented herein. A sensor system can comprise a sensor component comprising a sensor that generates an output signal based on an external excitation of the sensor; a sensitivity modification component that modifies a sensitivity of the sensor by a defined amount; and a calibration component that measures a first output value of the output signal before a modification of the sensitivity by the defined amount, measures a second output value of the output signal after the modification of the sensitivity by the defined amount, and determines, based on a difference between the first output value and the second output value, an offset portion of the output signal. Further, the calibration component can modify, based on the offset portion, the output signal.

Sensor self-calibration

A microelectromechanical (MEMS) accelerometer has a proof mass and a fixed electrode. The fixed electrode is located relative to the proof mass such that a capacitance formed by the fixed electrode and the proof mass changes in response to a linear acceleration along a sense axis of the accelerometer. The MEMS accelerometer is exposed to heat sources that produce a z-axis thermal gradient in MEMS accelerometer and an in-plane thermal gradient in the X-Y plane of the MEMS accelerometer. The z-axis thermal gradient is sensed with a plurality of thermistors located relative to anchoring regions of a CMOS layer of the MEMS accelerometer. The configuration of the thermistors within the CMOS layer measures the z-axis thermal gradient while rejecting other lateral thermal gradients. Compensation is performed at the accelerometer based on the z-axis thermal gradient.

Vertical thermal gradient compensation in a z-axis MEMS accelerometer

A microelectromechanical (MEMS) sensor comprises MEMS components located within a MEMS layer and located relative to one or more electrodes. A plurality of proof masses are located within the MEMS layer and are not electrically coupled to each other within the MEMS layer. Both the first proof mass and the second proof mass move relative to at least a common electrode of the one or more electrodes, such that the relative position of each of the proof masses relative to the electrode may be sensed. A sensed parameter may be determined based on the sensed relative positions.

Proof mass offset compensation

A device with a first MEMS device and a second MEMS device is disclosed. The first MEMS device is configured to sense at least one external influence. The second MEMS device is responsive to the at least one external influence. The first MEMS device is configured to change a state when the at least one external influence exceeds a threshold value. The first MEMS device is configured to retain the state below the threshold value, wherein the change in state of the first MEMS device is done passively and wherein the state of the first MEMS device is indicative of a status of the second MEMS device. In one example, the first MEMS device further comprises a normally open switch that closes when the external influence exceeds the threshold value.

Growing community of inventors

Beaverton, OR, United States of America

Matthew Julian Thompson