{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,20]],"date-time":"2026-06-20T03:27:57Z","timestamp":1781926077244,"version":"3.54.5"},"reference-count":22,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2014,9,3]],"date-time":"2014-09-03T00:00:00Z","timestamp":1409702400000},"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>An oxygen gas microsensor based on nanostructured sol-gel TiO2 thin films with a buried Pd layer was developed on a silicon substrate. The nanostructured titania thin films for O2 sensors were prepared by the sol-gel process and became anatase after heat treatment. A sandwich TiO2 square board with an area of 350 \u03bcm \u00d7 350 \u03bcm was defined by both wet etching and dry etching processes and the wet one was applied in the final process due to its advantages of easy control for the final structure. A pair of 150 nm Pt micro interdigitated electrodes with 50 nm Ti buffer layer was fabricated on the board by a  lift-off process. The sensor chip was tested in a furnace with changing the O2 concentration from 1.0% to 20% by monitoring its electrical resistance. Results showed that after several testing cycles the sensor\u2019s output becomes stable, and its sensitivity is 0.054 with deviation 2.65 \u00d7 10\u22124 and hysteresis is 8.5%. Due to its simple fabrication process, the sensor has potential for application in environmental monitoring, where lower power consumption and small size are required.<\/jats:p>","DOI":"10.3390\/s140916423","type":"journal-article","created":{"date-parts":[[2014,9,3]],"date-time":"2014-09-03T11:04:54Z","timestamp":1409742294000},"page":"16423-16433","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["A Micro Oxygen Sensor Based on a Nano Sol-Gel TiO2 Thin Film"],"prefix":"10.3390","volume":"14","author":[{"given":"Hairong","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University , Xi'an 710049, Shaanxi, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University , Xi'an 710049, Shaanxi, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaxin","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University , Xi'an 710049, Shaanxi, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quantao","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University , Xi'an 710049, Shaanxi, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yulong","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi'an Jiaotong University , Xi'an 710049, Shaanxi, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0925-4005(00)00639-0","article-title":"Micromachined metal oxide gas sensors: Opportunities to improve sensor performance","volume":"73","author":"Simon","year":"2001","journal-title":"Sens. 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