Freescale Semiconductor,inc.

Nxp USA, Inc.

Stmicroelectronics Gmbh

Bruno J Debeurre

Raimondo P Sessego

Tehmoor M Dar

Danielle A Thomas

Peter J Thoma

Aaron A Geisberger

Peter T Jones

Richard A Deken

Krithivasan Suryanarayanan

Chad S Dawson

William DeWitt McWhorter

A system includes a MEMS sensor having dual proof masses capable of moving independently from one another in response to forces imposed upon the proof masses. Each proof mass includes an independent set of sense contacts configured to provide output signals corresponding to the physical displacement of the corresponding sense mass. A switch system is in communication with the sense contacts. The switch system is configured to enable a sense mode and various test modes for the MEMS sensor. When the switch system enables a sense mode, output signals from the sense contacts can be combined to produce sense signals. When the switch system enables a test mode, the second contacts are electrically decoupled from one another to disassociate the output signals from one another. The independent sense contacts and switch system enable the concurrent compensation and calibration of the proof masses along two different sense axes.

Compensation and calibration of multiple mass MEMS sensor

A sensor system includes a microelectromechanical systems (MEMS) sensor, processing circuitry, measurement circuitry, stimulus circuitry and memory. The system is configured to provide an output responsive to physical displacement within the MEMS sensor to the measurement circuitry. The stimulus circuitry is configured to provide a stimulus signal to the MEMS sensor to cause a physical displacement within the MEMS sensor. The measurement circuitry is configured to process the output from the MEMS sensor and provide it to the processing circuitry, which is configured to generate stimulus signals and provide them to the stimulus circuitry for provision to the MEMS sensor. Output from the measurement circuitry corresponding to the physical displacement occurring in the MEMS sensor is monitored and used to calculate MEMS sensor characteristics. Methods for monitoring and calibrating MEMS sensors are also provided.

Compensation and calibration for MEMS devices

A method for testing a plurality of pressure sensors on a device wafer includes placing a diaphragm of one of the pressure sensors on the device wafer in proximity to a nozzle of a test system. A pneumatic pressure stimulus is applied to the diaphragm via an outlet of the nozzle and a cavity pressure is measured within a cavity associated with the pressure sensor in response to application of the pneumatic pressure stimulus. The pneumatic pressure stimulus within the cavity corresponds to the pressure applied to the diaphragm. Methodology is executed to test the strength and/or stiffness of the diaphragm. Additionally, the methodology and test system can be utilized to determine an individual calibration factor for each pressure sensor on the device wafer.

Methodology and system for wafer-level testing of MEMS pressure sensors

A sensor system includes a microelectromechanical systems (MEMS) sensor, control circuit, signal evaluation circuitry, a digital to analog converter, signal filters, an amplifier, demodulation circuitry and memory. The system is configured to generate high and low-frequency signals, combine them, and provide the combined input signal to a MEMS sensor. The MEMS sensor is configured to provide a modulated output signal that is a function of the combined signal. The system is configured to demodulate and filter the modulated output signal, compare the demodulated, filtered signal with the input signal to determine amplitude and phase differences, and determine, based on the amplitude and phase differences, various parameters of the MEMS sensor. A method for determining MEMS sensor parameters is also provided.

MEMS parameter identification using modulated waveforms

A sensor system includes a microelectromechanical systems (MEMS) sensor, a processor, measurement circuitry, stimulus circuitry and memory. The MEMS sensor is configured to provide an output responsive to physical displacement within the MEMS sensor to the measurement circuitry. The stimulus circuitry is configured to provide a stimulus signal to the MEMS sensor to cause a physical displacement within the MEMS sensor. The measurement circuitry is configured to process the output from the MEMS sensor and provide it to the processor. The processor is configured to generate stimulus signals and provide them to the stimulus circuitry for provision to the MEMS sensor. The processor is configured to monitor the output from the measurement circuitry corresponding to the physical displacement occurring in the MEMS sensor, calculate MEMS sensor characteristics based on the output, and update calibration values based on the output. Methods for monitoring and calibrating MEMS sensors are also provided.

MCU-based compensation and calibration for MEMS devices

A test structure includes two capacitor structures, wherein one of the capacitor structures has conductor plates spaced apart by a cavity, and the other capacitor structure does not include a cavity. Methodology entails forming the test structure and a pressure sensor on the same substrate using the same fabrication process techniques. Methodology for estimating the sensitivity of the pressure sensor includes detecting capacitances for each of the two capacitor structures and determining a ratio of the capacitances. A critical dimension of the cavity in one of the capacitor structures is estimated using the ratio, and the sensitivity of the pressure sensor is estimated using the critical dimension.

Test structure and methodology for estimating sensitivity of pressure sensors

Sensor cells are arranged in an array in an organic semiconductor layer. Row and column select circuitry addresses the cells of the array one cell at a time to determine the presence of an object, such as a fingerprint ridge or valley, contacting or proximate to a sensing surface above each cell. Control circuitry can be provided in a companion silicon chip or in a second layer of organic semiconductor material to communicate with the array and an associated system processor. The array of sensor cells can be fabricated using a flexible polymer substrate that is peeled off and disposed of after contacts have been patterned on the organic semiconductor layer. The organic semiconductor layer can be used with a superimposed reactive interface layer to detect specific chemical substances in a test medium.

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Phoenix, AZ, United States of America

Bruno J Debeurre