Analog Devices,inc.

Analog Devices International Unlimited Company

Michael W Judy

Xin Zhang

John R Martin

Howard R Samuels

Lawrence E Felton

John Albert Geen

Maurice S Karpman

Kemiao Jia

George M Molnar

Houri Johari-Galle

Christopher Needham

Chang-Han Yun

Kieran P Harney

Timothy J Brosnihan

Gaurav Vohra

Thomas Chen

John A Yasaitis

Colin Stephen Gormley

Peter Farrell

Bruce K Wachtmann

Roger T Howe

William Albert Clark

Jochen Schmitt

Susan A Alie

Jeffrey Ralph Swift

Jason W Weigold

Andrew William Sparks

Tao Yu

Harvey Weinberg

Stephen O'Brien

Igor P Prikhodko

Sushil Bharatan

Christine H Tsau

Yakov Reznichenko

Thor N Juneau

Eugene Oh Hwang

Timothy J Frey

Timothy Spooner

Phillip Nadeau

Enno Lage

David C Hollocher

Laura Cornelia Popa

Lewis Long

Mehrnaz Motiee

Andrew Proudman

Nikolay Pokrovskiy

David Kneedler

Kevin H-l Chau

Rui Zhang

Shanti Bhattacharya

Nelson Kuan

Venkataraman Chandrasekaran

Kevin H L Chau

Timothy J Brosnihhan

Nicole Hablutzel

Christophe Lemaire

H Jerome Barber

Chetan Paydenkar

Peter Meehan

A stress-isolated microelectromechanical systems (MEMS) device and a method of manufacture of the stress-isolated MEMS device are provided. MEMS devices may be sensitive to stress and may provide lower performance when subjected to stress. A stress-isolated MEMS device may be manufactured by etching a trench and/or a cavity in a first side of a substrate and subsequently forming a MEMS device on a surface of a platform opposite the first side of the substrate. Such a stress-isolated MEMS device may exhibit better performance than a MEMS device that is not stress-isolated. Moreover, manufacturing the MEMS device by first forming a trench and cavity on a backside of a wafer, before forming the MEMS device on a suspended platform, provides increased yield and allows for fabrication of smaller parts, in at least some embodiments.

Stress-isolated MEMS device comprising substrate having cavity and method of manufacture

The present disclosure provides a magnetic multi-turn sensor comprising a continuous coil of magnetoresistive elements and a method of manufacturing said sensor. The continuous coil is formed on a substrate such as a silicon wafer that has been fabricated so as to form a trench and bridge arrangement that enables the inner and outer spiral to be connected without interfering with the magnetoresistive elements of the spiral winding in between. Once the substrate has been fabricated with the trench and bridge arrangement, a film of the magnetoresistive material can be deposited to form a continuous coil on the surface of the substrate, wherein a portion of the coil is formed in the trench and a portion of the coil is formed on the bridge.

Magnetic multi-turn sensor and method of manufacture

A microelectromechanical systems (MEMS) accelerometer is provided, comprising a substrate disposed in a plane defined by a first axis and a second axis perpendicular to the first axis; a first proof mass and a second proof mass coupled to the substrate and configured to translate in opposite directions of each other along a third axis perpendicular to the first and second axes; and at least one lever coupling the first proof mass to the second proof mass, wherein, the MEMS accelerometer is configured to detect acceleration along the third axis via detection of translation of the first and second proof masses along the third axis; and the MEMS accelerometer exhibits symmetry about the first and second axes.

Accelerometer with translational motion of masses

Described herein are techniques for improving the signal-to-noise ratio of a wireless sensor platform. The device that interrogates a wireless sensor node (an interrogator) may be configured to determine the quantity to be measured by extracting information from multiple echoes produced in response to multiple interrogation pulses or produced due to multi-path propagation. Although different echoes may have been transformed to different extents, the echoes may share unique characteristics that are specific to the wireless sensor node that produced them. Accordingly, the SNR may be improved by keeping only portions of the received signal that exhibit such characteristics. The SNR may be further improved by summing the echoes together. In some embodiments, the echoes may be summed together in a coherent fashion, thereby producing an echo having an amplitude greater than the amplitude of each of the received echoes.

Coherent summation in wireless sensor platforms

An extensional mode electrostatic microelectromechanical systems (MEMS) gyroscope is described. The MEMS gyroscope operates in an extensional mode. The MEMS gyroscope comprises a vibrating ring structure that is electrostatically excited in the extensional mode.

Pseudo-extensional mode MEMS ring gyroscope

Single-axis teeter-totter accelerometers having a plurality of anchors are disclosed. The plurality of anchors may be arranged about a rotation axis of the teeter-totter proof mass. Each of the plurality of anchors may be coupled to the proof mass by two torsional springs each extending along the rotation axis. The plurality of anchors allows an increased number of torsional springs to be coupled to the proof mass and thus greater torsional stiffness for the proof mass may be achieved. Due to the higher torsional stiffness, the disclosed single-axis teeter-totter accelerometers may be deployed in high-frequency environments where such increased torsional stiffness is required, for example, around 20 kHz and above.

Multiple anchor high frequency accelerometer

Z-axis teeter-totter accelerometers with embedded movable structures are disclosed. The teeter-totter accelerometer may include an embedded mass which pivots or translates out-of-plane from the teeter-totter beam. The pivoting or translating embedded mass may be positioned to increase the sensitivity of the z-axis accelerometer by providing greater z-axis displacement than the teeter-totter beam itself exhibits.

Increased sensitivity z-axis accelerometer

A MEMS product includes a stress-isolated MEMS platform surrounded by a stress-relief gap and suspended from a substrate. The stress-relief gap provides a barrier against the transmission of mechanical stress from the substrate to the platform.

Stress isolation platform for MEMS devices

Multiple-axis resonant accelerometers are based on detection of resonance frequency changes of one or more electrostatically-driven resonator masses due to electrostatic gap changes under acceleration. Specifically, one or more resonator masses are configured to resonate simultaneously in different directions associated with different axes of sensitivity (e.g., X, Y, and/or Z axes). The motion of each resonator mass is monitored through one or more electrostatically-coupled sense electrodes. An acceleration along a particular axis of sensitivity causes a small change in the electrostatic gap(s) between the corresponding resonator mass(es) and the sense electrode(s) associated with that axis of sensitivity, and this electrostatic gap change manifests as a small change in the resonance frequency of the resonator from which an accelerometer output signal can be produced.

Multiple-axis resonant accelerometers

A microelectromechanical systems (MEMS) accelerometer is described. The MEMS accelerometer may comprise a proof mass configured to sense accelerations in a direction parallel the plane of the proof mass, and a plurality of compensation structures. The proof mass may be connected to one or more anchors through springs. The compensation structures may be coupled to the substrate of the MEMS accelerometer through a rigid connection to respective anchors. A compensation structure may comprise at least one compensation electrode forming one or more lateral compensation capacitors. The compensation capacitor(s) may be configured to sense displacement of the anchor to which the compensation structures is connected.

Anchor tracking apparatus for in-plane accelerometers and related methods

In one aspect, the disclosure is directed to a MEMS device. The MEMS device includes a silicon-based movable MEMS sensor element. The MEMS device also includes a plurality of wells formed into at least one surface of the movable MEMS sensor element. Each well is filled with at least one metal so as to increase the effective mass of the movable MEMS sensor element. The metal may be tungsten or tantalum, or an alloy with tungsten or tantalum.

Silicon-based MEMS devices including wells embedded with high density metal

An encapsulated MEMS device includes stress-relief trenches in a region of its substrate that surrounds the movable micromachined structures and that is covered by a cap, such that the trenches are fluidly exposed to a cavity between the substrate and the cap. A method of fabricating a MEMS device includes fabricating stress-relief trenches through a substrate and fabricating movable micromachined structures, and capping the device prior art encapsulating the device.

MEMS device with stress relief structures

An MEMS device has a dynamically variable reference capacitor that provides a reference to a sense capacitance. In some embodiments, a 3-axis accelerometer includes a proof mass suspended above a substrate from an anchor, and a cantilevered Z-axis reference capacitor arm suspended above the substrate from the same anchor. In some embodiments, the proof mass is suspended from a plurality of anchors, and each anchor also supports one or more cantilevered arms, the cantilevered arms forming a dynamically variable reference capacitance.

MEMS sensor with dynamically variable reference capacitance

A single-axis tilt-mode microelectromechanical accelerometer structure. The structure includes a substrate having a top surface defined by a first end and a second end. Coupled to the substrate is a first asymmetrically-shaped mass suspended above the substrate pivotable about a first pivot point on the substrate between the first end and the second end and a second asymmetrically-shaped mass suspended above the substrate pivotable about a second pivot point on the substrate between the first end and the second end. The structure also includes a first set of electrodes positioned on the substrate and below the first asymmetrically-shaped mass and a second set of electrodes positioned on the substrate and below the second asymmetrically-shaped mass.

Tilt mode accelerometer with improved offset and noise performance

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Wakefield, MA, United States of America

Michael W Judy