{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:06:22Z","timestamp":1787029582508,"version":"3.56.0"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2009,4,21]],"date-time":"2009-04-21T00:00:00Z","timestamp":1240272000000},"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>In the study, a MEMS-based benzene gas sensor is presented, consisting of a quartz substrate, a thin-film WO3 sensing layer, an integrated Pt micro-heater, and Pt interdigitated electrodes (IDEs). When benzene is present in the atmosphere, oxidation occurs on the heated WO3 sensing layer. This causes a change in the electrical conductivity of the WO3 film, and hence changes the resistance between the IDEs. The benzene concentration is then computed from the change in the measured resistance. A specific orientation of the WO3 layer is obtained by optimizing the sputtering process parameters. It is found that the sensitivity of the gas sensor is optimized at a working temperature of 300 \u00b0C. At the optimal working temperature, the experimental results show that the sensor has a high degree of sensitivity (1.0 K\u03a9 ppm-1), a low detection limit (0.2 ppm) and a rapid response time (35 s).<\/jats:p>","DOI":"10.3390\/s90402895","type":"journal-article","created":{"date-parts":[[2009,4,21]],"date-time":"2009-04-21T10:25:34Z","timestamp":1240309534000},"page":"2895-2906","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":83,"title":["A MEMS-based Benzene Gas Sensor with a Self-heating WO3 Sensing Layer"],"prefix":"10.3390","volume":"9","author":[{"given":"Ming-Tsun","family":"Ke","sequence":"first","affiliation":[{"name":"Department of Energy and Refrigerating Air-conditioning Engineering, National Taipei University of Technology, Taiwan, Taiwan 106"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mu-Tsun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Energy and Refrigerating Air-conditioning Engineering, National Taipei University of Technology, Taiwan, Taiwan 106"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chia-Yen","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, National Pingtung University of Science and Technology, Pingtung, Taiwan 912"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lung-Ming","family":"Fu","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, National Pingtung University of Science and Technology, Pingtung, Taiwan 912"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2009,4,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1111\/j.1600-0668.2004.00297.x","article-title":"Detection of single and mixed VOCs by small and by sensory irritation","volume":"14","author":"Cain","year":"2004","journal-title":"Indoor Air"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.snb.2004.01.015","article-title":"Pt-loaded Al2O3 catalytic filters for screen-printed WO3 sensors highly selective to benzene","volume":"101","author":"Malysz","year":"2004","journal-title":"Sens. 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