{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:11:11Z","timestamp":1760209871269,"version":"build-2065373602"},"reference-count":85,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2017,6,30]],"date-time":"2017-06-30T00:00:00Z","timestamp":1498780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008231","name":"Arkansas Biosciences Institute","doi-asserted-by":"publisher","award":["Arkansas Tobacco Settlement Proceeds Act of 2000"],"award-info":[{"award-number":["Arkansas Tobacco Settlement Proceeds Act of 2000"]}],"id":[{"id":"10.13039\/100008231","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000930","name":"NSF","doi-asserted-by":"publisher","award":["1460754"],"award-info":[{"award-number":["1460754"]}],"id":[{"id":"10.13039\/501100000930","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Iraqi Ministry of Higher Education and Scientific Research","award":["MoHESR"],"award-info":[{"award-number":["MoHESR"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work investigates a new design for a plasmonic SERS biosensor via computational electromagnetic models. It utilizes a dual-width plasmonic grating design, which has two different metallic widths per grating period. These types of plasmonic gratings have shown larger optical enhancement than standard single-width gratings. The new structures have additional increased enhancement when the spacing between the metal decreases to sub-10 nm dimensions. This work integrates an oxide layer to improve the enhancement even further by carefully studying the effects of the substrate oxide thickness on the enhancement and reports ideal substrate parameters. The combined effects of varying the substrate and the grating geometry are studied to fully optimize the device\u2019s enhancement for SERS biosensing and other plasmonic applications. The work reports the ideal widths and substrate thickness for both a standard and a dual-width plasmonic grating SERS biosensor. The ideal geometry, comprising a dual-width grating structure atop an optimal SiO2 layer thickness, improves the enhancement by 800%, as compared to non-optimized structures with a single-width grating and a non-optimal oxide thickness.<\/jats:p>","DOI":"10.3390\/s17071530","type":"journal-article","created":{"date-parts":[[2017,6,30]],"date-time":"2017-06-30T10:04:58Z","timestamp":1498817098000},"page":"1530","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Substrate Oxide Layer Thickness Optimization for a Dual-Width Plasmonic Grating for Surface-Enhanced Raman Spectroscopy (SERS) Biosensor Applications"],"prefix":"10.3390","volume":"17","author":[{"given":"Stephen","family":"Bauman","sequence":"first","affiliation":[{"name":"Microelectronics-Photonics Graduate Program, 731 W. Dickson St., University of Arkansas, Fayetteville, Arkansas, AR 72701, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zachary","family":"Brawley","sequence":"additional","affiliation":[{"name":"Department of Physics, 825 W. Dickson St., University of Arkansas, Fayetteville, Arkansas, AR 72701, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmad","family":"Darweesh","sequence":"additional","affiliation":[{"name":"Microelectronics-Photonics Graduate Program, 731 W. Dickson St., University of Arkansas, Fayetteville, Arkansas, AR 72701, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2441-6169","authenticated-orcid":false,"given":"Joseph","family":"Herzog","sequence":"additional","affiliation":[{"name":"Microelectronics-Photonics Graduate Program, 731 W. Dickson St., University of Arkansas, Fayetteville, Arkansas, AR 72701, USA"},{"name":"Department of Physics, 825 W. Dickson St., University of Arkansas, Fayetteville, Arkansas, AR 72701, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"484","DOI":"10.1038\/nature10016","article-title":"Probing cellular protein complexes using single-molecule pull-down","volume":"473","author":"Jain","year":"2011","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1002\/adfm.200901993","article-title":"Enhanced Fluorescence Microscopic Imaging by Plasmonic Nanostructures: From a 1D Grating to a 2D Nanohole Array","volume":"20","author":"Cui","year":"2010","journal-title":"Adv. Funct. 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