{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T14:33:58Z","timestamp":1770561238302,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,1,26]],"date-time":"2018-01-26T00:00:00Z","timestamp":1516924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001711","name":"Schweizerischer Nationalfonds zur F\u00f6rderung der Wissenschaftlichen Forschung","doi-asserted-by":"publisher","award":["200021E-160347\/1"],"award-info":[{"award-number":["200021E-160347\/1"]}],"id":[{"id":"10.13039\/501100001711","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a gas sensitive thin-film transistor (TFT) based on an amorphous Indium\u2013Gallium\u2013Zinc\u2013Oxide (a-IGZO) semiconductor as the sensing layer, which is fabricated on a free-standing flexible polyimide foil. The photo-induced sensor response to NO2 gas at room temperature and the cross-sensitivity to humidity are investigated. We combine the advantages of a transistor based sensor with flexible electronics technology to demonstrate the first flexible a-IGZO based gas sensitive TFT. Since flexible plastic substrates prohibit the use of high operating temperatures, the charge generation is promoted with the help of UV-light absorption, which ultimately triggers the reversible chemical reaction with the trace gas. Furthermore, the device fabrication process flow can be directly implemented in standard TFT technology, allowing for the parallel integration of the sensor and analog or logical circuits.<\/jats:p>","DOI":"10.3390\/s18020358","type":"journal-article","created":{"date-parts":[[2018,1,26]],"date-time":"2018-01-26T07:31:51Z","timestamp":1516951911000},"page":"358","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":68,"title":["Photo-Induced Room-Temperature Gas Sensing with a-IGZO Based Thin-Film Transistors Fabricated on Flexible Plastic Foil"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2946-3992","authenticated-orcid":false,"given":"Stefan","family":"Knobelspies","sequence":"first","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benedikt","family":"Bierer","sequence":"additional","affiliation":[{"name":"Laboratory for Gas Sensors, Department of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7461-3756","authenticated-orcid":false,"given":"Alwin","family":"Daus","sequence":"additional","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alain","family":"Takabayashi","sequence":"additional","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giovanni","family":"Salvatore","sequence":"additional","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6398-601X","authenticated-orcid":false,"given":"Giuseppe","family":"Cantarella","sequence":"additional","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alvaro","family":"Ortiz Perez","sequence":"additional","affiliation":[{"name":"Laboratory for Gas Sensors, Department of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00fcrgen","family":"W\u00f6llenstein","sequence":"additional","affiliation":[{"name":"Laboratory for Gas Sensors, Department of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany"},{"name":"Fraunhofer Institute for Physical Measurement Techniques, Freiburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2109-1936","authenticated-orcid":false,"given":"Stefan","family":"Palzer","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Universidad Aut\u00f3noma de Madrid, Francisco Tom\u00e1s y Valiente 11, 28049 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gerhard","family":"Tr\u00f6ster","sequence":"additional","affiliation":[{"name":"Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Z\u00fcrich, Gloriastrasse 35, 8092 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"WHO (2009). 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