In described examples, a cavity is formed between a substrate and a cap. One or more access holes are formed through the cap for removing portions of a sacrificial layer from within the cavity. A cover is supported by the cap, where the cover is for occulting the one or more access holes along a perspective. An encapsulant seals the cavity, where the encapsulant encapsulates the cover and the one or more access holes.

A microelectromechanical systems (MEMS) sensor, a capacitive MEMS motor sensing circuit and a method are provided. The present application provides a microelectromechanical systems (MEMS) sensor. The MEMS sensor includes a housing having electrical contacts disposed on an exterior of the housing. The MEMS sensor further includes a capacitive MEMS motor disposed in the housing, and an electrical circuit disposed in the housing and being electrically coupled to the electrical contacts. The electrical circuit includes a bias voltage source having an output coupled to an input of the MEMS motor. The electrical circuit further includes a buffer circuit including an amplifier input stage having an input coupled to an output of the MEMS motor. The electrical circuit still further includes a frequency dependent input attenuator including a feedback capacitor and an input attenuator low pass filter, the input attenuator low pass filter having an input coupled to the output of the amplifier input stage and an output coupled to a first terminal of the feedback capacitor, where a second terminal of the feedback capacitor is coupled to the input of the amplifier input stage.

The present invention generally relates to an RF MEMS DVC and a method for manufacture thereof. To ensure that undesired grain growth does not occur and contribute to an uneven RF electrode, a multilayer stack comprising an AlCu layer and a layer containing titanium may be used. The titanium diffuses into the AlCu layer at higher temperatures such that the grain growth of the AlCu will be inhibited and the switching element can be fabricated with a consistent structure, which leads to a consistent, predictable capacitance during operation.

Devices and methods of operating partitioned actuator plates to obtain a desirable shape of a movable component of a micro-electro-mechanical system (MEMS) device. The subject matter described herein can in some embodiments include a micro-electro-mechanical system (MEMS) device including a plurality of actuation electrodes attached to a first surface, where each of the one or more actuation electrode being independently controllable, and a movable component spaced apart from the first surface and movable with respect to the first surface. Where the movable component further includes one or more movable actuation electrodes spaced apart from the plurality of fixed actuation electrodes.

A sensor having a particle barrier is described. In an example, a sensor includes: first and second electrode sets respectively disposed upon a planar support surface and a proof mass that is compliantly displaceable along a first axis substantially parallel to the planar support surface; and a first barrier disposed on the planar support around the first electrode set having a height less than a gap between the planar support and the proof mass to mitigate particle migration into the first or second electrode set.

A method for forming a MEMS device may include performing a silicon-on-nothing process to form a cavity in a monocrystalline silicon substrate at a first depth relative to a top surface of the monocrystalline silicon substrate; forming, in an electrically conductive electrode region of the monocrystalline silicon substrate, an electrically insulated region extending to a second depth that is less than the first depth relative to the top surface of the monocrystalline silicon substrate; and etching the monocrystalline silicon substrate to expose a gap between a first electrode and a second electrode, wherein the second electrode is separated from the first electrode, within a first depth region, by a first distance defined by the electrically insulated region and the gap, and wherein the second electrode is separated from the first electrode, within a second depth region, by a second distance defined by the gap.

A system includes a sensor device, a circuit driving he sensor device at a drive frequency, a receiver, and a low pass filter. The sensor device is configured to change its electrical characteristics in response to external stimuli. The sensor device generates a modulated signal proportional to the external stimuli. The receiver is configured to receive the modulated signal and further configured to demodulate the modulated signal to generate a demodulated signal. The demodulation signal has a guard band. The receiver consumes power responsive to receiving the modulated signal. The low pass filter is configured to receive the demodulated signal and further configured to generate a sensor output.

A MEMS device includes a backplate electrode and a membrane disposed spaced apart from the backplate electrode. The membrane includes a displaceable portion and a fixed portion. The backplate electrode and the membrane are arranged such that an overlapping area of the fixed portion of the membrane with the backplate electrode is less than maximum overlapping.

A button device includes a MEMS sensor having a MEMS strain detection structure and a deformable substrate configured to undergo deformation under the action of an external force. The MEMS strain detection structure includes a mobile element carried by the deformable substrate via at least a first and a second anchorage, the latter fixed with respect to the deformable substrate and configured to displace and generate a deformation force on the mobile element in the presence of the external force; and stator elements capacitively coupled to the mobile element. The deformation of the mobile element causes a capacitance variation between the mobile element and the stator elements. Furthermore, the MEMS sensor is configured to generate detection signals correlated to the capacitance variation.

A method for forming a MEMS device may include performing a silicon-on-nothing process to form a cavity in a monocrystalline silicon substrate at a first depth relative to a top surface of the monocrystalline silicon substrate; forming, in an electrically conductive electrode region of the monocrystalline silicon substrate, an electrically insulated region extending to a second depth that is less than the first depth relative to the top surface of the monocrystalline silicon substrate; and etching the monocrystalline silicon substrate to expose a gap between a first electrode and a second electrode, wherein the second electrode is separated from the first electrode, within a first depth region, by a first distance defined by the electrically insulated region and the gap, and wherein the second electrode is separated from the first electrode, within a second depth region, by a second distance defined by the gap.