{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T04:19:07Z","timestamp":1777436347268,"version":"3.51.4"},"reference-count":29,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2014,3,3]],"date-time":"2014-03-03T00:00:00Z","timestamp":1393804800000},"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 humidity microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 \u03bcm CMOS (complementary metal oxide semiconductor) process was presented. The integrated sensor chip consists of a humidity sensor and a readout circuit. The humidity sensor is composed of a sensitive film and interdigitated electrodes. The sensitive film is titanium dioxide prepared by the sol-gel method. The titanium dioxide is coated on the interdigitated electrodes. The humidity sensor requires a post-process to remove the sacrificial layer and to coat the titanium dioxide. The resistance of the sensor changes as the sensitive film absorbs or desorbs vapor. The readout circuit is employed to convert the resistance variation of the sensor into the output voltage. The experimental results show that the integrated humidity sensor has a sensitivity of  4.5 mV\/RH% (relative humidity) at room temperature.<\/jats:p>","DOI":"10.3390\/s140304177","type":"journal-article","created":{"date-parts":[[2014,3,3]],"date-time":"2014-03-03T11:27:10Z","timestamp":1393846030000},"page":"4177-4188","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Titanium Dioxide Nanoparticle Humidity Microsensors Integrated with Circuitry on-a-Chip"],"prefix":"10.3390","volume":"14","author":[{"given":"Yu-Chih","family":"Hu","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, National Chung Hsing University, Taichung 402, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ching-Liang","family":"Dai","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Chung Hsing University, Taichung 402, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Chih","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Electro-Optical Engineering, Yuan Ze University, Taoyuan 320, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Gardner, J.W., Varadan, V.K., and Awadelkarim, O.O. 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