Freescale Semiconductor,inc.

Nxp USA, Inc.

Dubravka Bilic

Andrew C McNeil

Chad S Dawson

Lianjun Liu

Stephen Ryan Hooper

Aaron A Geisberger

Margaret Leslie Kniffin

Fengyuan Li

Colin Bryant Stevens

Marco Fuhrmann

Thomas D Ohe

Methods for fabricating crack resistant Microelectromechanical (MEMS) devices are provided, as are MEMS devices produced pursuant to such methods. In one embodiment, the method includes forming a sacrificial body over a substrate, producing a multi-layer membrane structure on the substrate, and removing at least a portion of the sacrificial body to form an inner cavity within the multi-layer membrane structure. The multi-layer membrane structure is produced by first forming a base membrane layer over and around the sacrificial body such that the base membrane layer has a non-planar upper surface. A predetermined thickness of the base membrane layer is then removed to impart the base membrane layer with a planar upper surface. A cap membrane layer is formed over the planar upper surface of the base membrane layer. The cap membrane layer is composed of a material having a substantially parallel grain orientation.

Microelectromechanical system devices having crack resistant membrane structures and methods for the fabrication thereof

A differential capacitive output pressure sensor device includes a pressure sensor diaphragm layer comprising a pressure sensing diaphragm portion, a movable electrode on the pressure sensing diaphragm portion, a fixed electrode, and a device layer electrode. The pressure sensor device further includes a device layer including a fixed element connected to the device layer electrode and a movable element connected to the movable electrode. As the pressure changes, the pressure sensing diaphragm portion including the movable electrode and the movable element move. This changes the capacitance between the movable electrode and the fixed element inversely to the change in capacitance between the fixed electrode and the moveable element. Accordingly, a differential capacitive output is provided that has improved linearity with respect to the pressure change and increased sensitivity allowing the change in pressure to be measured readily and accurately.

Differential capacitive output pressure sensor and method

A structure for preventing charge induced leakage of a semiconductor device includes a shield separated from a first interconnect by at least a first lateral spacing and separated from a second interconnect by at least a second lateral spacing. The first interconnect is connected to a first junction and the second interconnect is connected to a second junction. A shield bias is connected to the shield to terminate an electromagnetic field on the shield. The shield between the first and second lateral spacings has a minimum width to substantially prevent formation of a conductive channel between the first and second junctions. The shield may be formed over a portion of the first junction and over a portion of the second junction to substantially prevent formation of another conductive channel between the first and second junctions at a location that does not have the first and second lateral spacings.

Actively preventing charge induced leakage of semiconductor devices

During a first cycle of operation, first and second bottom electrodes of a split bottom electrode are electrically connected together. A total capacitance between the split bottom electrode and a top electrode layer is measured to determine the ambient pressure. Accordingly, pressure, e.g., tire pressure, is measured during the first cycle of operation. In a second cycle of operation, the first and second bottom electrodes are electrically disconnected. A first capacitance between the first bottom electrode and top electrode layer and a second capacitance between second bottom electrode and top electrode layer are measured. The difference between the first capacitance and the second capacitance is calculated and compared to a fault indicating capacitance variation to determine if the pressure sensor device is operating normally or malfunctioning. Accordingly, a self-test of the pressure sensor device is performed during the second cycle of operation.

Self test for capacitive pressure sensors

A microelectromechanical system (MEMS) sensor device includes a substrate, a support structure supported by the substrate, a membrane supported by the support structure and spaced from the substrate, and a polymer layer covering the membrane.

Sensor protective coating

A method of fabricating a sensor device includes forming a plurality of sensor structures on a wafer, covering the plurality of sensor structures with a polymer layer, and dicing the wafer into a plurality of die while each sensor structure remains covered by the polymer layer.

A combination sensor and corresponding method of measuring a plurality of environmental parameters uses a pressure sensor disposed on an integrated circuit die; a humidity sensor disposed on the integrated circuit die; and a circuit coupled to and shared by the pressure sensor and the humidity sensor to facilitate pressure and humidity sensing.

Combined environmental parameter sensor

A pressure sensor includes a first set of electrodes, a second set of electrodes, and a common electrode. The first and second sets of electrodes overlie an insulative surface, wherein the first set of electrodes represent sense capacitor bottom electrodes and the second set of electrodes represent reference capacitor bottom electrodes. The second set of electrodes is configured in an interleaved arrangement with the first set of electrodes, wherein the geometry of individual electrodes of the first set of electrodes substantially matches the geometry of individual electrodes of the second set of electrodes. In addition, the common electrode represents a sense and reference capacitor top electrode that is (i) overlying, (ii) spaced from, and (iii) configured in connection with the first and second sets of electrodes to form a common pressure cavity, wherein the common electrode includes first portions corresponding to sense membrane portions and second portions corresponding to reference membrane portions, further wherein an area of a sense membrane portion is greater than an area of a reference membrane portion.

Pressure sensor featuring offset cancellation and method of making

A capacitor assembly () is formed on a substrate (). The capacitor assembly a first conductive plate () and a second conductive plate () formed over the substrate such that the second conductive plate is separated from the first conductive plate by a distance. A conductive trace () is formed over the substrate that is connected to the first conductive plate and extends away from the capacitor assembly. A conductive shield () is formed over at least a portion of the conductive trace that is separated from the first and second conductive plates to control a fringe capacitance between the second conductive plate and the conductive trace.

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Scottsdale, AZ, United States of America

Dubravka Bilic