{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T05:39:45Z","timestamp":1775367585203,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,4]],"date-time":"2022-02-04T00:00:00Z","timestamp":1643932800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Chemiresistive graphene sensors are promising for chemical sensing applications due to their simple device structure, high sensitivity, potential for miniaturization, low-cost, and fast response. In this work, we investigate the effect of (1) ZnO nanoparticle functionalization and (2) engineered defects onto graphene sensing channel on device resistance and low frequency electrical noise. The engineered defects of interest include 2D patterns of squares, stars, and circles and 1D patterns of slots parallel and transverse to the applied electric potential. The goal of this work is to determine which devices are best suited for chemical sensing applications. We find that, relative to pristine graphene devices, nanoparticle functionalization leads to reduced contact resistance but increased sheet resistance. In addition, functionalization lowers 1\/f current noise on all but the uniform mesa device and the two devices with graphene strips parallel to carrier transport. The strongest correlations between noise and engineering defects, where normalized noise amplitude as a function of frequency f is described by a model of AN\/f\u03b3, are that \u03b3 increases with graphene area and contact area but decreases with device total perimeter, including internal features. We did not find evidence of a correlation between the scalar amplitude, AN, and the device channel geometries. In general, for a given device area, the least noise was observed on the least-etched device. These results will lead to an understanding of what features are needed to obtain the optimal device resistance and how to reduce the 1\/f noise which will lead to improved sensor performance.<\/jats:p>","DOI":"10.3390\/s22031183","type":"journal-article","created":{"date-parts":[[2022,2,6]],"date-time":"2022-02-06T20:40:18Z","timestamp":1644180018000},"page":"1183","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Electrical and Low Frequency Noise Characterization of Graphene Chemical Sensor Devices Having Different Geometries"],"prefix":"10.3390","volume":"22","author":[{"given":"JongBong","family":"Nah","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, George Mason University, Fairfax, VA 22030, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Frank Keith","family":"Perkins","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2426-8493","authenticated-orcid":false,"given":"Evgeniya H.","family":"Lock","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anindya","family":"Nath","sequence":"additional","affiliation":[{"name":"Global Foundries Inc., 1000 River St, Essex Junction, VT 05452, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anthony","family":"Boyd","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rachael L.","family":"Myers-Ward","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David Kurt","family":"Gaskill","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"},{"name":"Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Osofsky","sequence":"additional","affiliation":[{"name":"U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mulpuri V.","family":"Rao","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, George Mason University, Fairfax, VA 22030, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1167","DOI":"10.1021\/es902659d","article-title":"Toward Ubiquitous Environmental Gas Sensors\u2014Capitalizing on the Promise of Graphene","volume":"44","author":"Ratinac","year":"2010","journal-title":"Environ. 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