Invensense, Inc.

Leland Stanford Junior University

Goksen G Yaralioglu

Joseph Seeger

Steven Saeed Nasiri

Butrus Thomas Khuri-Yakub

Babak A Taheri

Martin Lim

Baris Cagdaser

Hasan Akyol

Arif Sanli Ergun

Fahrettin Levent Degertekin

Ilya Gurin

Igor Tchertkov

Alexander Castro

Bruno Borovic

Hemanth Jagannathan

A rotational sensor for measuring rotational acceleration is disclosed. The rotational sensor comprises a sense substrate; at least two proof masses, and a set of two transducers. Each of the at least two proof masses is anchored to the sense substrate via at least one flexure and electrically isolated from each other; and the at least two proof masses are capable of rotating in-plane about a Z-axis relative to the sense substrate, wherein the Z-axis is normal to the substrate. Each of the transducers can sense rotation of each proof mass with respect to the sense substrate in response to a rotation of the rotational sensor.

MEMS rotation sensor with integrated electronics

A system and method for controlling temperature of a MEMS sensor are disclosed. In a first aspect, the system comprises a MEMS cap encapsulating the MEMS sensor and a CMOS die vertically arranged to the MEMS cap. The system includes a heater integrated into the MEMS cap. The integrated heater is activated to control the temperature of the MEMS sensor. In a second aspect, the method comprises encapsulating the MEMS sensor with a MEMS cap and coupling a CMOS die to the MEMS cap. The method includes integrating a heater into the MEMS cap. The integrated heater is activated to control the temperature of the MEMS sensor.

Integrated heater on MEMS cap for wafer scale packaged MEMS sensors

Sensors for measuring angular acceleration about three mutually orthogonal axes, X, Y, Z or about the combination of these axes are disclosed. The sensor comprises a sensor subassembly. The sensor subassembly further comprises a base which is substantially parallel to the X-Y sensing plane; a proof mass disposed in the X-Y sensing plane and constrained to rotate substantially about the X, and/or Y, and/or Z, by at least one linkage and is responsive to angular accelerations about the X, and/or Y, and/or Z directions. Finally, the sensor includes at least one electrode at the base plate or perpendicular to the base plate and at least one transducer for each sensing direction of the sensor subassembly responsive to the angular acceleration. Multi-axis detection is enabled by adjusting a configuration of flexures and electrodes.

Vertically integrated 3-axis MEMS angular accelerometer with integrated electronics

A system and method is disclosed that provides a technique for generating an accurate time base for MEMS sensors and actuators which has a vibrating MEMS structure. The accurate clock is generated from the MEMS oscillations and converted to the usable range by means of a frequency translation circuit.

Method and system for using a MEMS structure as a timing source

In a method and system in accordance with the present invention, solder balls are added on top of vertically integrated MEMS with CMOS by using wafer scale fabrication compatible with existing chip scale packaging capabilities. In the present invention, both the MEMS and the CMOS dies are fabricated in equal dimensions. On the MEMS level, silicon islands are defined by DRIE etching to be bonded on top of CMOS pads. These conducting silicon islands later provide electrical connections between the CMOS pads and the conducting traces that lead to solder balls on top.

Wafer scale chip scale packaging of vertically integrated MEMS sensors with electronics

A system and method in accordance with the present invention provides for a low cost, bulk micromachined accelerometer integrated with electronics. The accelerometer can also be integrated with rate sensors that operate in a vacuum environment. The quality factor of the resonances is suppressed by adding dampers. Acceleration sensing in each axis is achieved by separate structures where the motion of the proof mass affects the value of sense capacitors differentially. Two structures are used per axis to enable full bridge measurements to further reduce the mechanical noise, immunity to power supply changes and cross axis coupling. To reduce the sensitivity to packaging and temperature changes, each mechanical structure is anchored to a single anchor pillar bonded to the top cover.

Vertically integrated 3-axis MEMS accelerometer with electronics

An anchoring assembly for anchoring MEMS device is disclosed. The anchoring assembly comprises: a top substrate; a bottom substrate substantially parallel to the top substrate; and a first portion of the anchor between the top substrate and the bottom substrate. The first portion of the anchor is rigidly connected to the top substrate; and the first portion of the anchor is rigidly connected to the bottom substrate. A second portion of the anchor is between the top substrate and the bottom substrate. The second portion of the anchor is rigidly connected to the top substrate; the second portion of the anchor being an anchoring point for the MEMS device. A substantially flexible mechanical element coupling the first portion of the anchor and the second portion of the anchor; the flexible element providing the electrical connection between the first portion of the anchor and the second portion of the anchor.

Performance-enhancing two-sided MEMS anchor design for vertically integrated micromachined devices

A mechanical resonator capable of providing an intrinsically high mechanical quality factor in immersion is provided. The resonator includes a membrane attached at its perimeter to a frame, such that a front side of the membrane is in contact with the liquid, and the back side of the membrane is not in contact with the liquid or the frame. The membrane can act as a mechanical resonator. The quality factor of this resonator is enhanced by providing a pressure release boundary region on the frame in proximity to the membrane and in contact with the liquid. The pressure release boundary region provides a soft boundary condition, in the sense that a mechanical impedance on the solid side of the solid-liquid interface is less than the liquid mechanical impedance. Providing such a soft boundary condition reduces the mechanical energy loss due to excitation of waves in the liquid, thereby improving resonator quality factor. Such high-Q resonators are particularly useful for sensor applications.

High quality factor resonators for liquid immersion biological and chemical sensors

A capacitive membrane ultrasonic transducer which includes a membrane supported by a substrate in which ultrasonic bulk waves at the frequency of operation of the transducers are suppressed by configuring the substrate and a method of suppressing the ultrasonic bulk waves.

Capacitive membrane ultrasonic transducers with reduced bulk wave generation and method

There is described a method and apparatus for measuring temperature of a fluid in a microchannel of the type having spaced walls. An ultrasonic transducer transmits ultrasonic waves transmitted from one wall to the opposite wall. A processor determines the time-of-flight of the ultrasonic waves from the one wall and reflected to the opposite wall to the one wall. The processor converts the time-of-flight to velocity by dividing the distance between walls by the time-of-flight. The processor converts velocity to temperature from the relationship of velocity to temperature in the fluid.

Microfluidic channels with integrated ultrasonic transducers for temperature measurement and method

An optical displacement sensor is provided for optically measuring the static and dynamic displacement of one or more reflectors that can be integrated in electronics and optics applications. The sensor includes an optically transparent substrate and a reflective grating deposited on the substrate. A light source provides optical illumination on the reflector through the substrate and the reflective grating. The reflector is positioned over the substrate and over the reflective grating. Furthermore, one or more photo-detectors are included to monitor reflected and diffracted light from the reflector and the reflective grating. The position of the reflector can be adjusted by applying at least one DC voltage. An AC signal could be added to at least one DC bias voltage for calibration of the sensor. The present invention also includes an array of reflectors as well as a transmission grating to deflect the optical illumination to the array of reflectors.

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Mountain View, CA, United States of America

Goksen G Yaralioglu