High performance tri-axial piezoresistive accelerometer

摘要

The invention is on a bulk-micromachining tri-axial piezoresistive accelerometer characterised by highly symmetric mechanical structure with four surrounding beams. New mechanical structure (figure 3) and measurement circuit (figure 4) have been developed, respect to prior state-of-art technology, which maximize sensor measurement accuracy. The combination of both novelty allows increasing the device sensitivity and simultaneously reducing the total cross-axis sensitivity (0.4%), hence improving the measurement accuracy of current state-of-art technology of similar devices. Moreover the sensitivity remains constant for any in-plane acceleration (acceleration on X-Y plane, uniaxial or biaxial), therefore improving the static device response.;The benefits of the invention are independent from the device size features, therefore the invention can be used for designing accelerometer for various purposes.