{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T01:13:29Z","timestamp":1760404409236,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2011,1,19]],"date-time":"2011-01-19T00:00:00Z","timestamp":1295395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A small, highly sensitive, and electromagnetic interference (EMI)-immune refractive index (RI) sensor based on the Fabry-Perot (FP) interferometer is presented. The sensor\u2019s FP cavity was fabricated by aligning two metal-deposited, single-mode optical fiber endfaces inside a microchannel on a silicon chip. The mirrors on the fiber endfaces were made of thermal-deposited metal films, which provided the high finesse necessary to produce a highly sensitive sensor. Microelectromechanical systems (MEMS) fabrication techniques, specifically photolithography and deep dry etching, were used to precisely control the profile and depth of the microchannel on the silicon chip with an accuracy of 2 \u03bcm. The RI change within the FP cavity was determined by demodulating the transmission spectrum phase shift. The sensitivity and finesse of the transmission spectrum were controlled by adjusting the cavity length and the thickness of the deposited metal. Our experimental results showed that the sensor\u2019s sensitivity was 665.90 nm\/RIU (RI Unit), and the limit of detection was 6 \u00d7 10\u22126 RIU. Using MEMS fabrication techniques to fabricate these sensors could make high yield mass production a real possibility. Multiple sensors could be integrated on a single small silicon chip to simultaneously measure RI, temperature, and biomolecule targets.<\/jats:p>","DOI":"10.3390\/s110101078","type":"journal-article","created":{"date-parts":[[2011,1,19]],"date-time":"2011-01-19T12:16:40Z","timestamp":1295439400000},"page":"1078-1087","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["A Miniature Fiber Optic Refractive Index Sensor Built in a MEMS-Based Microchannel"],"prefix":"10.3390","volume":"11","author":[{"given":"Ye","family":"Tian","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenhui","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaotian","family":"Zou","sequence":"additional","affiliation":[{"name":"Biomedical Engineering and Biotechnology Doctoral Program, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charles","family":"Guthy","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xingwei","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"},{"name":"Biomedical Engineering and Biotechnology Doctoral Program, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1016\/j.snb.2005.09.006","article-title":"High-resolution refractive index sensing by means of a multiple-peak surface plasmon resonance optical fiber sensor","volume":"115","author":"Villatoro","year":"2006","journal-title":"Sens. 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