Silicon Microstructures, Inc.

Elmos Semiconductor Ag

Michael B Doelle

Bernd Burchard

Richard John August

Zhou Ningning

Joachim Bergmann

Pressure sensors having components with reduced variations due to stresses caused by various layers and components that are included in the manufacturing process. In one example, a first stress in a first direction causes a variation in a component. A second stress in a second direction is applied, thereby reducing the variation in the component. The first and second stresses may be caused by a polysilicon layer, while the component may be a resistor in a Wheatstone bridge.

Compensation of stress effects on pressure sensor components

Circuits, methods, and systems that calibrate or account for packaging and related stress components in a pressure sensor. Further examples provide an improved sensor element or device. One example provides one or more sensing elements on the diaphragm and near the diaphragm-bulk boundary. Sensors near the diaphragm-bulk are used to estimate package-induced stress. This estimation can then be used in calibrating package stress from pressure measurements.

Sensor element placement for package stress compensation

Circuits, methods, and systems to compensate pressure sensor readings for changes in temperature. An example measures temperature in a field-effect-transistor-based pressure sensor or micro-electromechanical system by measuring the device's threshold voltage. This threshold voltage is linearly dependent on the temperature but shows negligible sensitivity to mechanical stress. This allows the pressure sensor's temperature to be determined in an environment of changing pressure. Once the temperature is known, the pressure sensor's pressure readings can be adjusted. The threshold voltage can be extracted by measuring the turn-on transistor characteristic of the device and using device models. Alternately, the threshold voltage can be extracted using threshold voltage extraction circuits.

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Mountain View, CA, United States of America

Michael B Doelle