{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T12:47:50Z","timestamp":1772455670404,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,5,5]],"date-time":"2022-05-05T00:00:00Z","timestamp":1651708800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Marie Sk\u0142odowska-Curie","award":["101030887"],"award-info":[{"award-number":["101030887"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, different planar inductor topologies were studied to evaluate their characteristic parameters\u2019 variation range upon approaching Fe- and Cu-based shield plates. The use of such materials can differently alter the electrical properties of planar inductors such as the inductance, resonant frequency, resistance, and quality factor, which could be useful in multiple devices, particularly in inductive sensing and radio-frequency (or RF) applications. To reach an optimal design, five different square topologies, including spiral, tapered, non-spiral, meander, and fractal, were built on a printed circuit board (PCB) and assessed experimentally. At the working frequency of 1 MHz, the results showed a decrease in the inductance value when approaching a Cu-based plate and an increase with Fe-based plates. The higher variation range was noticeable for double-layer topologies, which was about 60% with the Cu-based plate. Beyond an intrinsic deflection frequency, the inductance value began to decrease when approaching the ferromagnetic plate because of the ferromagnetic resonance (FMR). It has been shown that the FMR frequency depends on the inductor topology and is larger for the double-layer spiral one. The Q-factor was decreasing for all topologies but was much faster when using ferromagnetic plates because of the FMR, which intensely increases the track resistance. The resonant frequency was increasing for all double-layer topologies and decreasing for single-layer ones, which was mainly due to the percentage change in the stray capacitance compared to the inductance variation. The concept of varying inductors by metal shielding plates has great potential in a wide range of nondestructive sensing and RF applications.<\/jats:p>","DOI":"10.3390\/s22093514","type":"journal-article","created":{"date-parts":[[2022,5,6]],"date-time":"2022-05-06T02:46:39Z","timestamp":1651805199000},"page":"3514","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Variation Range of Different Inductor Topologies with Shields for RF and Inductive Sensing Applications"],"prefix":"10.3390","volume":"22","author":[{"given":"Fares","family":"Tounsi","sequence":"first","affiliation":[{"name":"Sensors, Microsystems and Actuators Laboratory of Louvain (SMALL), Universit\u00e9 Catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium"},{"name":"Systems Integration & Emerging Energies (SI2E), National Engineering School of Sfax, University of Sfax, Route Soukra, BP 1173, Sfax 3038, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohamed Hadj","family":"Said","sequence":"additional","affiliation":[{"name":"Systems Integration & Emerging Energies (SI2E), National Engineering School of Sfax, University of Sfax, Route Soukra, BP 1173, Sfax 3038, Tunisia"},{"name":"Center for Research in Microelectronics and Nanotechnology (CRMN), Sousse 4050, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Margo","family":"Hauwaert","sequence":"additional","affiliation":[{"name":"Sensors, Microsystems and Actuators Laboratory of Louvain (SMALL), Universit\u00e9 Catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sinda","family":"Kaziz","sequence":"additional","affiliation":[{"name":"Systems Integration & Emerging Energies (SI2E), National Engineering School of Sfax, University of Sfax, Route Soukra, BP 1173, Sfax 3038, Tunisia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4683-3916","authenticated-orcid":false,"given":"Laurent A.","family":"Francis","sequence":"additional","affiliation":[{"name":"Sensors, Microsystems and Actuators Laboratory of Louvain (SMALL), Universit\u00e9 Catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Pierre","family":"Raskin","sequence":"additional","affiliation":[{"name":"Sensors, Microsystems and Actuators Laboratory of Louvain (SMALL), Universit\u00e9 Catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Denis","family":"Flandre","sequence":"additional","affiliation":[{"name":"Sensors, Microsystems and Actuators Laboratory of Louvain (SMALL), Universit\u00e9 Catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1109\/TED.2003.810474","article-title":"On the design of RF spiral inductors on silicon","volume":"50","author":"Burghartz","year":"2003","journal-title":"IEEE Trans. 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