{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:39:47Z","timestamp":1760243987769,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2009,3,19]],"date-time":"2009-03-19T00:00:00Z","timestamp":1237420800000},"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>For the miniaturization of ISFET sensing systems,the concept of a REFET with low ion sensitivity is proposed to replace the conventional reference electrodes through the arrangement of a quasi reference electrode and a differential readout circuit. In this study, an ion-unblocking membrane was used as the top layer of a REFET. To optimize the REFET performance, the influences of the silylating process, different plasticizers, and the composition of the PVC cocktails were investigated. A low sensitivity (10.4 \u00b1 2.2 mV\/pH) and high linearity (99.7 \u00b1 0.3 %) in the range from pH 2.2 to pH 11.6 was obtained for the REFET with a 60\u02dawt.% DNP\/(DNP + PVC) membrane. To evaluate the long term stability, the drift coefficient was estimated, and for the best REFET, it was \u20130.74 mV\/h. Two criteria for assessing the lifetime of REFETs were used, namely the increase in pH sensitivity to a value higher than 15 mV\/pH and the degradation of linearity below 99 %. For the best REFET, it was approximately 15 days.<\/jats:p>","DOI":"10.3390\/s90302076","type":"journal-article","created":{"date-parts":[[2009,3,20]],"date-time":"2009-03-20T01:52:51Z","timestamp":1237513971000},"page":"2076-2087","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Optimization of a PVC Membrane for Reference Field Effect Transistors"],"prefix":"10.3390","volume":"9","author":[{"given":"Chao-Sung","family":"Lai","sequence":"first","affiliation":[{"name":"Department of Electronic Engineering in Chang Gung University. \/ 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, Taiwan, 333, R.O.C."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-En","family":"Lue","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering in Chang Gung University. \/ 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan, Taiwan, 333, R.O.C."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chia-Ming","family":"Yang","sequence":"additional","affiliation":[{"name":"Device Section, Department of WAT and Devices, Inotera Memories Inc. \/ 667, Fuhsing 3rd Road, Hwa-Ya Technology Park, Kwei-Shan, Tao-Yuan, Taiwan. R.O. C."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marek","family":"Dawgul","sequence":"additional","affiliation":[{"name":"Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences \/ ul. Trojdena 4, 02-109 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dorota G.","family":"Pijanowska","sequence":"additional","affiliation":[{"name":"Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences \/ ul. Trojdena 4, 02-109 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2009,3,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1109\/TBME.1970.4502688","article-title":"Development of an ion-sensitive solid state device for neurophysiological measurements","volume":"BME-17","author":"Bergveld","year":"1970","journal-title":"IEEE Trans. Biomed. 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