Mcube, Inc.

Sudheer S Sridharamurthy

Wenhua Zhang

Shingo Yoneoka

Ali J Rastegar

Sanjay Bhandari

Te-Hsi Terrence Lee

Xiao Charles Yang

Daniel N Koury, Jr

Te-Hsi “Terrence” Lee

Terrence Lee

Te-Hse Terrence Lee

Mugurel Stancu

Xiao “Charles” Yang

Tony Maraldo

Joseph Rastegar

Zheng-Yao Sun

A structure for a MEMS device includes a MEMS layer comprising a mass portion and a spring portion, a substrate coupled to the MEMS layer, wherein the substrate comprises a planar region and an stopper region, wherein the MEMS device and the substrate are oriented in a plurality of relative orientations in response to an external force, wherein the spring portion and the stopper region are configured to disengagingly impact when the external force exceeds a first threshold force, wherein the mass portion and the planar region are configured to disengagingly impact when the external force exceeds a second threshold force, and wherein the second threshold force exceeds the first threshold force.

MEMS device with reduced dynamic stress and methods

A method for a MEMS device comprises determining in a computer system, a first driving signal for the MEMS device in response to a first time delay and to a base driving signal, applying the first driving signal to the MEMS device to induce the MEMS device to operate at a first frequency, determining a second driving signal for the MEMS device in response to a second time delay and to the base driving signal, applying the second driving signal to the MEMS device to induce the MEMS device to operate at a second frequency, determining a first quality factor associated with the MEMS device in response to the first frequency and the second frequency, determining a quality factor associated with the MEMS device in response to the first quality factor, and determining whether the quality factor associated with the MEMS device, exceeds a threshold quality factor.

Method to test the quality factor of a MEMS gyroscope at chip probe

A multi-axis integrated MEMS inertial sensor device. The device can include an integrated 3-axis gyroscope and 3-axis accelerometer on a single chip, creating a 6-axis inertial sensor device. The structure is spatially configured with efficient use of the design area of the chip by adding the accelerometer device to the center of the gyroscope device. The design architecture can be a rectangular or square shape in geometry, which makes use of the whole chip area and maximizes the sensor size in a defined area. The MEMS is centered in the package, which is beneficial to the sensor's temperature performance. Furthermore, the electrical bonding pads of the integrated multi-axis inertial sensor device can be configured in the four corners of the rectangular chip layout. This configuration guarantees design symmetry and efficient use of the chip area.

Multi-axis integrated MEMS inertial sensing device on single packaged chip

A CMOS IC substrate can include sense amplifiers, demodulation circuits and AGC loop circuit coupled to the MEMS gyroscope. The AGC loop acts in a way such that generated desired signal amplitude out of the drive signal maintains MEMS resonator velocity at a desired frequency and amplitude. The system can include charge pumps to create higher voltages as required in the system. The system can incorporate ADC to provide digital outputs that can be read via serial interface such as I2C. The system can also include temperature sensor which can be used to sense and output temperature of the chip and system and can be used to internally or externally compensate the gyroscope sensor measurements for temperature related changes. The CMOS IC substrate can be part of a system which can include a MEMS gyroscope having a MEMS sensor overlying the CMOS IC substrate.

Integrated inertial sensing device

A method for fabricating an integrated MEMS-CMOS device. The method can include providing a substrate member having a surface region and forming a CMOS IC layer having at least one CMOS device overlying the surface region. A bottom isolation layer can be formed overlying the CMOS IC layer and a shielding layer and a top isolation layer can be formed overlying a portion of bottom isolation layer. The bottom isolation layer can include an isolation region between the top isolation layer and the shielding layer. A MEMS layer overlying the top isolation layer, the shielding layer, and the bottom isolation layer, and can be etched to form at least one MEMS structure having at least one movable structure and at least one anchored structure.

MEMS structure with improved shielding and method

A MEMS rate sensor device. In an embodiment, the sensor device includes a MEMS rate sensor configured overlying a CMOS substrate. The MEMS rate sensor can include a driver set, with four driver elements, and a sensor set, with six sensing elements, configured for 3-axis rotational sensing. This sensor architecture allows low damping in driving masses and high damping in sensing masses, which is ideal for a MEMS rate sensor design. Low driver damping is beneficial to MEMS rate power consumption and performance, with low driving electrical potential to achieve high oscillation amplitude.

Multi-axis MEMS rate sensor device

An integrated circuit includes a substrate member having a surface region and a CMOS IC layer overlying the surface region. The CMOS IC layer has at least one CMOS device. The integrated circuit also includes a bottom isolation layer overlying the CMOS IC layer, a shielding layer overlying a portion of the bottom isolation layer, and a top isolation layer overlying a portion of the bottom isolation layer. The bottom isolation layer includes an isolation region between the top isolation layer and the shielding layer. The integrated circuit also has a MEMS layer overlying the top isolation layer, the shielding layer, and the bottom isolation layer. The MEMS layer includes at least one MEMS structure having at least one movable structure and at least one anchored structure. The at least one anchored structure is coupled to a portion of the top isolation layer, and the at least one movable structure overlies the shielding layer.

A method for fabricating an integrated MEMS-CMOS device uses a micro-fabrication process that realizes moving mechanical structures (MEMS) on top of a conventional CMOS structure by bonding a mechanical structural wafer on top of the CMOS and etching the mechanical layer using plasma etching processes, such as Deep Reactive Ion Etching (DRIE). During etching of the mechanical layer, CMOS devices that are directly connected to the mechanical layer are exposed to plasma. This sometimes causes permanent damage to CMOS circuits and is termed Plasma Induced Damage (PID). Embodiments of the present invention presents methods and structures to prevent or reduce this PID and protect the underlying CMOS circuits by grounding and providing an alternate path for the CMOS circuits until the MEMS layer is completely etched.

Methods and structures of integrated MEMS-CMOS devices

A system can include a MEMS gyroscope having a MEMS resonator overlying a CMOS IC substrate. The CMOS IC substrate can include an AGC loop circuit coupled to the MEMS gyroscope. The AGC loop acts in a way such that generated desired signal amplitude out of the drive signal maintains MEMS resonator velocity at a desired frequency and amplitude. A benefit of the AGC loop is that the charge pump of the HV driver inherently includes a 'time constant' for charging up of its output voltage. The system incorporates the Low pass functionality in to the AGC loop without requiring additional circuitry.

An improved MEMS transducer apparatus and method is provided. The apparatus has a movable base structure including an outer surface region and at least one portion removed to form at least one inner surface region. At least one intermediate anchor structure is disposed within the inner surface region. The apparatus includes an intermediate spring structure operably coupled to the central anchor structure, and at least one portion of the inner surface region. A capacitor element is disposed within the inner surface region.

Transducer structure and method for MEMS devices

An integrated MEMS inertial sensor device. The device includes a MEMS inertial sensor overlying a CMOS substrate. The MEMS inertial sensor includes a drive frame coupled to the surface region via at least one drive spring, a sense mass coupled to the drive frame via at least a sense spring, and a sense electrode disposed underlying the sense mass. The device also includes at least one pair of quadrature cancellation electrodes disposed within a vicinity of the sense electrode, wherein each pair includes an N-electrode and a P-electrode.

Method and structure of an integrated MEMS inertial sensor device using electrostatic quadrature-cancellation

A method and structure for fabricating an inertial sensing device using tilt conversion to sense a force in the out-of-plane direction. The method can include forming anchor structure(s) coupled to portions of a surface region of a substrate member. Also, the method can include forming flexible anchor members coupled to portions of the anchor structures and frame structures, which can be formed overlying the substrate. The method can also include forming flexible frame members coupled to portions of the frame structures and movable structures, which can also be formed overlying the substrate. Forming the movable structures can include forming peripheral and central movable structures, which can be coupled to flexible structure members. Peripheral movable structures having flexible tilting members can convert a pure tilting out-of-plane motion to a pure translational out-of-plane motion. The forming of these elements can include performing an etching process on a single silicon material.

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Menlo Park, CA, United States of America

Sudheer S Sridharamurthy