Nxp B.v.

Other

Twan Van Lippen

Remco Henricus Wilhelmus Pijnenburg

Iris Bominaar-Silkens

Geert Langereis

Klaus Reimann

Peter Dirksen

Peter G Steeneken

Jozef Thomas Martinus Van Beek

Robert Hendrikus Margaretha Van Veldhoven

Martijn Goossens

Hilco Suy

Reinout Woltjer

Frank Pasveer

Franz Felberer

Rodolf Herfst

Andres Felipe Vasquez Quintero

Sima Tarashioon

A capacitive micro-electromechanical system (MEMS) microphone includes a semiconductor substrate having an opening that extends through the substrate. The microphone has a membrane that extends across the opening and a back-plate that extends across the opening. The membrane is configured to generate a signal in response to sound. The back-plate is separated from the membrane by an insulator and the back-plate exhibits a spring constant. The microphone further includes a back-chamber that encloses the opening to form a pressure chamber with the membrane, and a tuning structure configured to set a resonance frequency of the back-plate to a value that is substantially the same as a value of a resonance frequency of the membrane.

Micro-electromechanical system microphone

A read out circuit for a sensor uses a feedback loop to bias the sensor to a desired operating point, such as the maximal possible sensitivity, but without the problem of an instable sensor position as known for the conventional read-out with constant charge. The reference bias to which the circuit is controlled is also varied using feedback control, but with a slower response than the main bias control feedback loop.

Sensor circuit and calibration method

The present invention provides a capacitive MEMS device comprising a first electrode lying in a plane, and a second electrode suspended above the first electrode and movable with respect to the first electrode. The first electrode functions as an actuation electrode. A gap is present between the first electrode and the second electrode. A third electrode is placed intermediate the first and second electrode with the gap between the third electrode and the second electrode. The third electrode has one or a plurality of holes therein, preferably in an orderly or irregular array. An aspect of the present invention integration of a conductive, e.g. metallic grating as a middle (or third) electrode. An advantage of the present invention is that it can reduce at least one problem of the prior art. This advantage allows an independent control over the pull-in and release voltage of a switch.

RF MEMS switch with a grating as middle electrode

A MEMS device, such as a microphone, uses a fixed perforated plate. The fixed plate comprises an array of holes across the plate area. At least a set of the holes adjacent the outer periphery comprises a plurality of rows of elongate holes, the rows at different distances from the periphery. This design improves the mechanical robustness of the membrane and can additionally allow tuning of the mechanical behavior of the plate.

Acoustic transducers with perforated membranes

A MEMS device, such as a microphone, uses a perforated plate. The plate comprises an array of holes across the plate area. The plate has an area formed as a grid of polygonal cells, wherein each cell comprises a line of material following a path around the polygon thereby defining an opening in the center. In one aspect, the line of material forms a path along each side of the polygon which forms a track which extends at least once inwardly from the polygon perimeter towards the center of the polygon and back outwardly to the polygon perimeter. This defines a meandering hexagon side wall, which functions as a local spring suspension.

The invention relates to a method for manufacturing a micromachined microphone and an accelerometer from a waferhaving a first layer, the method comprising the steps of dividing the first layerinto a microphone layerand into an accelerometer layer, covering a front side of the microphone layerand a front side of the accelerometer layerwith a continuous second layer, covering the second layerwith a third layer, forming a plurality of trenchesin the third layer, removing a partof the waferbelow a back side of the microphone layer, forming at least two wafer trenchesin the waferbelow a back side of the accelerometer layer, and removing a partof the second layerthrough the plurality of trenchesformed in the third layer. The micromachined microphone and the accelerometer according to the invention is advantageous over prior art as it allows for body noise cancellation in order to minimize structure borne sound.

Microphone and accelerometer

A MEMS manufacturing method and device in which a spacer layer is provided over a side wall of at least one opening in a structural layer which will define the movable MEMS element. The opening extends below the structural layer. The spacer layer forms a side wall portion over the side wall of the at least one opening and also extends below the level of the structural layer to form a contact area.

MEMS device and manufacturing method

A capacitive sensor is configured for collapsed mode, e.g. for measuring sound or pressure, wherein the moveable element is partitioned into smaller sections. The capacitive sensor provides increased signal to noise ratio.

Collapsed mode capacitive sensor

A MEMS accelerometer uses capacitive sensing between two electrode layers. One of the electrode layers has at least four independent electrodes arranged as two pairs of electrodes, with one pair aligned orthogonally to the other such that tilting of the membrane can be detected as well as normal-direction movement of the membrane. In this way, a three axis accelerometer can be formed from a single suspended mass, and by sensing using a set of capacitor electrodes which are all in the same plane. This means the fabrication is simple and is compatible with other MEMS manufacturing processes, such as MEMS microphones.

MEMS accelerometer using capacitive sensing and production method thereof

A microphone and a method for manufacturing the same. The microphones includes a substrate die; and a microphone and an accelerometer formed from the substrate die. The accelerometer is adapted to provide a signal for compensating mechanical vibrations of the substrate die.

Microphone

Proximity sensor, particularly for usage in an electronic mobile device, comprising at least one acoustic transducer adapted for receiving acoustic signals at least in parts of the frequency range of human audible sound and emitting and/or receiving ultrasonic signals for proximity estimation. The acoustic transducer preferably is a Micro-Electro-Mechanical-Systems (MEMS) microphone. Further, a method in an electronic device comprising an acoustic transducer is provided comprising the steps of generating at least one electric signal in the frequency range of ultrasonic sound, emitting at least one ultrasonic signal by means of the acoustic transducer; receiving at least one ultrasonic signal by means of the acoustic transducer; deducing from the at least one emitted ultrasonic signal and the at least one received ultrasonic signal at least the delay between emission of the emitted ultrasonic signal and reception of the corresponding ultrasonic signal.

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Bladel, Netherlands

Twan Van Lippen