{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T06:21:15Z","timestamp":1774765275581,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,13]],"date-time":"2019-09-13T00:00:00Z","timestamp":1568332800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present the design, fabrication, and response of a polymer-based Laterally Amplified Chemo-Mechanical (LACM) humidity sensor based on mechanical leveraging and parametric amplification. The device consists of a sense cantilever asymmetrically patterned with a polymer and flanked by two stationary electrodes on the sides. When exposed to a humidity change, the polymer swells after absorbing the analyte and causes the central cantilever to bend laterally towards one side, causing a change in the measured capacitance. The device features an intrinsic gain due to parametric amplification resulting in an enhanced signal-to-noise ratio (SNR). Eleven-fold magnification in sensor response was observed via voltage biasing of the side electrodes without the use of conventional electronic amplifiers. The sensor showed a repeatable and recoverable capacitance change of 11% when exposed to a change in relative humidity from 25\u201385%. The dynamic characterization of the device also revealed a response time of ~1 s and demonstrated a competitive response with respect to a commercially available reference chip.<\/jats:p>","DOI":"10.3390\/s19183954","type":"journal-article","created":{"date-parts":[[2019,9,13]],"date-time":"2019-09-13T10:32:41Z","timestamp":1568370761000},"page":"3954","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Parametrically Amplified Low-Power MEMS Capacitive Humidity Sensor"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3138-118X","authenticated-orcid":false,"given":"Rugved","family":"Likhite","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aishwaryadev","family":"Banerjee","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Apratim","family":"Majumder","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohit","family":"Karkhanis","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6576-5125","authenticated-orcid":false,"given":"Hanseup","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carlos H.","family":"Mastrangelo","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1016\/0250-6874(86)80055-5","article-title":"Humidity sensors: Principles and applications","volume":"10","author":"Yamazoe","year":"1986","journal-title":"Sens. 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