{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T02:07:04Z","timestamp":1768442824675,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2010,3,3]],"date-time":"2010-03-03T00:00:00Z","timestamp":1267574400000},"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>The study presents a micro carbon monoxide (CO) sensor integrated with a readout circuit-on-a-chip manufactured by the commercial 0.35 \u03bcm complementary metal oxide semiconductor (CMOS) process and a post-process. The sensing film of the sensor is a composite cobalt oxide nanosheet and carbon nanotube (CoOOH\/CNT) film that is prepared by a precipitation-oxidation method. The structure of the CO sensor is composed of a polysilicon resistor and a sensing film. The sensor, which is of a resistive type, changes its resistance when the sensing film adsorbs or desorbs CO gas. The readout circuit is used to convert the sensor resistance into the voltage output. The post-processing of the sensor includes etching the sacrificial layers and coating the sensing film. The advantages of the sensor include room temperature operation, short response\/recovery times and easy post-processing. Experimental results show that the sensitivity of the CO sensor is about 0.19 mV\/ppm, and the response and recovery times are 23 s and 34 s for 200 ppm CO, respectively.<\/jats:p>","DOI":"10.3390\/s100301753","type":"journal-article","created":{"date-parts":[[2010,3,3]],"date-time":"2010-03-03T11:01:12Z","timestamp":1267614072000},"page":"1753-1764","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Cobalt Oxide Nanosheet and CNT Micro Carbon Monoxide Sensor Integrated with Readout Circuit on Chip"],"prefix":"10.3390","volume":"10","author":[{"given":"Ching-Liang","family":"Dai","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, National Chung Hsing University, Taichung, 402 Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yen-Chi","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Chung Hsing University, Taichung, 402 Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chyan-Chyi","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Electro-Mechanical Engineering, Tamkang University, Tamsui, 251 Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chin-Fu","family":"Kuo","sequence":"additional","affiliation":[{"name":"Microsystems Technology Center, Industrial Technology Research Institute, Tainan, 709 Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2010,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1016\/j.snb.2003.12.051","article-title":"High sensitivity Pt-doped SnO2 gas sensors fabricated using sol\u2013gel solution on micromachined (1 0 0) Si substrates","volume":"100","author":"Esfandyarpour","year":"2004","journal-title":"Sens. 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