Abstract:
A method of manufacturing an integrated circuit including a MEMS device includes forming a structural layer above a substrate including at least one semiconductor device. The method includes forming an attachment to a first portion of the structural layer, the attachment having a thickness substantially greater than a thickness of the structural layer. In at least one embodiment of the method, the attachment is conjoined with the first portion of the structural layer and the first portion of the structural layer and the attachment are operative to mechanically move in unison. In at least one embodiment of the method, forming the attachment includes forming a patterned filler layer of a first material above the structural layer and forming a patterned conformal layer of a second material on the patterned filler layer. The filler layer has a thickness substantially greater than the thickness of the structural layer.
Abstract:
In at least one embodiment of the invention, a method of manufacturing an integrated circuit including a microelectromechanical system (MEMS) device includes forming a first structural layer above at least one semiconductor device formed on a substrate. The method includes forming a second structural layer above the first structural layer. The second structural layer has a thickness substantially greater than a thickness of the first structural layer. The MEMS device comprises at least one portion of at least one of the first and second structural layers. In at least one embodiment of the invention, the method is carried out at one or more temperatures less than a tolerable threshold temperature for the at least one semiconductor device.
Abstract:
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.
Abstract:
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.
Abstract:
A dual in-situ mixing approach for extended tuning range of resonators. In one embodiment, a dual in-situ mixing device tunes an input radio-frequency (RF) signal using a first mixer, a resonator body, and a second mixer. In one embodiment, the first mixer is coupled to receive the input RF signal and a local oscillator signal. The resonator body receives the output of the first mixer, and the second mixer is coupled to receive the output of the resonator body and the local oscillator signal to provide a tuned output RF signal as a function of the frequency of local oscillator signal.
Abstract:
A magnetic sensor utilizes a MEMS device that has at least one vibrating member and at least one conductive path integral with the vibrating member so that a current flows along the vibrating member and in the presence of a magnetic field interaction of the magnetic field and the point charges in the current on the conductive path due to the Lorentz force causes a change in vibration of the vibrating member. That change can be used to provide a measure of the magnetic field.
Abstract:
Low temperature, multi-layered, planar microshells for encapsulation of devices such as MEMS and microelectronics. The microshells include a planar perforated pre-sealing layer, below which a non-planar sacrificial layer is accessed, and a sealing layer to close the perforation in the pre-sealing layer after the sacrificial material is removed. In an embodiment, the pre-sealing layer has perforations formed with a damascene process to be self-aligned to the chamber below the microshell. The sealing layer may include a nonhermetic layer to physically occlude the perforation and a hermetic layer over the nonhermetic occluding layer to seal the perforation. In a particular embodiment, the hermetic layer is a metal which is electrically coupled to a conductive layer adjacent to the microshell to electrically ground the microshell.
Abstract:
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.
Abstract:
An apparatus and a method for compensating for a mismatch in temperature coefficients of two oscillator frequencies to match a desired frequency ratio between the two oscillator frequencies over a temperature range. In one embodiment of a temperature sensor, first and second oscillators of different temperature characteristics are coupled to a differential frequency discriminator (DFD) circuit. The DFD circuit compensates for the different characteristics in order to match a frequency difference between the first and second frequencies over a temperature range.
Abstract:
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.