Silicon Laboratories Inc.

Semiconductor Manufacturing International (Shanghai) Corporation

Mehrnaz Motiee

Emmanuel Philippe Quevy

David H Bernstein

Jeremy R Hui

Carrie Wing-Zin Low

Jeffrey Lee Sonntag

Roger T Howe

Aaron J Caffee

Manu Seth

Brian G Drost

David A Bernstein

Methods and structures that may be implemented in one example to co-integrate processes for thin-film encapsulation and formation of microelectronic devices and microelectromechanical systems (MEMS) such as sensors and actuators. For example, structures having varying characteristics may be fabricated using the same basic process flow by selecting among different process options or modules for use with the basic process flow in order to create the desired structure/s. Various process flow sequences as well as a variety of device design structures may be advantageously enabled by the various disclosed process flow sequences.

Methods and structures for thin-film encapsulation and co-integration of same with microelectronic devices and microelectromechanical systems (MEMS)

An apparatus includes a microelectromechanical system (MEMS) device. The MEMS device includes a resonator suspended from a substrate, an anchor disposed at a center of the resonator, a plurality of suspended beams radiating between the anchor and the resonator, a plurality of first electrodes disposed about the anchor, and a plurality of second electrodes disposed about the anchor. The plurality of first electrodes and the resonator form a first electrostatic transducer. The plurality of second electrodes and the resonator form a second electrostatic transducer. The first electrostatic transducer and the second electrostatic transducer are configured to sustain rotational vibrations of the resonator at a predetermined frequency about an axis through the center of the resonator and orthogonal to a plane of the substrate in response to a signal on the first electrode.

Rotational MEMS resonator for oscillator applications

A microelectromechanical system (MEMS) device includes a resonator anchored to a substrate. The resonator includes a first strain gradient statically deflecting a released portion of the resonator in an out-of-plane direction with respect to the substrate. The resonator includes a first electrode anchored to the substrate. The first electrode includes a second strain gradient of a released portion of the first electrode. The first electrode is configured to electrostatically drive the resonator in a first mode that varies a relative amount of displacement between the resonator and the first electrode. The resonator may include a resonator anchor anchored to the substrate. The first electrode may include an electrode anchor anchored to the substrate in close proximity to the resonator anchor. The electrode anchor may be positioned relative to the resonator anchor to substantially decouple dynamic displacements of the resonator relative to the electrode from changes to the substrate.

Out-of-plane resonator

A method of forming a microelectromechanical systems (MEMS) device includes forming an electrode on a substrate. The method includes forming a structural layer on the substrate. The structural layer is disposed about a perimeter of the electrode and has a residual film stress gradient. The method includes releasing the structural layer to form a resonator coupled to the substrate. The residual film stress gradient deflects a first portion of the resonator out of a plane defined by a surface of the electrode.

Out-of plane MEMS resonator with static out-of-plane deflection

A MEMS oscillator includes a resonator body and primary and secondary drive electrodes to electrostatically drive the resonator body. Primary and secondary sense electrodes sense motion of the resonator body. The primary and secondary drive and sense electrodes are configured to be used together during start-up of the MEMS oscillator. The secondary drive electrode and secondary sense electrode are disabled after start-up, while the primary drive and sense electrodes remain enabled to maintain oscillation.

Switchable electrode for power handling

A microelectromechanical systems (MEMS) device includes a tuning electrode, a drive electrode, and a resonator. The resonator is anchored to a substrate and is configured to resonate in response to a signal on the drive electrode. The MEMS device includes a tuning plate coupled to the resonator and positioned above the tuning electrode. The tuning plate is configured to adjust a resonant frequency of the resonator in response to a voltage difference between the resonator and the tuning electrode. In at least one embodiment of the MEMS device, the tuning plate and the tuning electrode are configured to adjust the resonant frequency of the resonator substantially independent of the signal on the drive electrode.

Out-of-plane MEMS resonator with static out-of-plane deflection

A residual stress gradient in a structural layer is employed to form a resonator deflected out of plane when at rest and the resulting strain gradient is utilized in out-of-plane transduction. Use of the strain gradient enables out-of-plane (e.g., vertical) transduction without yield and reliability problems due to stiction (e.g., the sticking of the resonator to the substrate) when the resonator is driven by an electrode to dynamically deflect out-of-plane. In particular embodiments, out-of-plane transduction is utilized to achieve better transduction efficiency as compared to lateral resonator designs of similar linear dimensions (i.e. footprint) results in a lower motional resistance.

A MEMS structure having a temperature-compensated resonator member is described. The MEMS structure comprises an asymmetric stress inverter member coupled with a substrate. A resonator member is housed in the asymmetric stress inverter member and is suspended above the substrate. The asymmetric stress inverter member is used to alter the thermal coefficient of frequency of the resonator member by inducing a stress on the resonator member in response to a change in temperature.

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San Francisco, CA, United States of America

Mehrnaz Motiee