Perspectives on MEMS in bioengineering: a novel capacitive position microsensor.

A Pedrocchi; S Hoen; G Ferrigno; A Pedotti

doi:10.1109/10.817612

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Perspectives on MEMS in bioengineering: a novel capacitive position microsensor.

A Pedrocchi·S Hoen·G Ferrigno·A Pedotti

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Abstract

We describe a novel capacitive position sensor using micromachining to achieve high sensitivity and large range of motion. These sensors require a new theoretical framework to describe and optimize their performance. Employing a complete description of the electrical fields, the sensor should deviate from the standard geometries used for capacitive sensors. By this optimization, the sensor gains a twofold increase in sensitivity. Results on a PC board 10x model imply that the micromachined sensor should achieve a sensitivity of less than 10 nm over 500-micron range of travel. Some bioengineering applications are addressed, including positioning of micromirrors for laser surgery and dose control for implantable drug delivery systems.

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A Pedrocchi, S Hoen, G Ferrigno, A Pedotti. 2000. Perspectives on MEMS in bioengineering: a novel capacitive position microsensor.. https://doi.org/10.1109/10.817612

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