{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:33:11Z","timestamp":1760239991636,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,2,6]],"date-time":"2019-02-06T00:00:00Z","timestamp":1549411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund and regional government (JCCLM)","award":["SBPLY\/17\/180501\/000139"],"award-info":[{"award-number":["SBPLY\/17\/180501\/000139"]}]},{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["FPU-AP2010-6069","FPI-BES-2013-063743"],"award-info":[{"award-number":["FPU-AP2010-6069","FPI-BES-2013-063743"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 \u00b5m and thicknesses between 10 and 60 \u00b5m is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 \u00d7 900 \u00d7 10 \u00b5m3 cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10\u22126 g\/mL and 10\u22124 mPa\u00b7s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.<\/jats:p>","DOI":"10.3390\/s19030658","type":"journal-article","created":{"date-parts":[[2019,2,6]],"date-time":"2019-02-06T11:51:12Z","timestamp":1549453872000},"page":"658","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["A Geometrical Study on the Roof Tile-Shaped Modes in AlN-Based Piezoelectric Microcantilevers as Viscosity\u2013Density Sensors"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0568-2974","authenticated-orcid":false,"given":"V\u00edctor","family":"Ruiz-D\u00edez","sequence":"first","affiliation":[{"name":"Microsystems, Actuators and Sensors Group, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8114-7252","authenticated-orcid":false,"given":"Javier","family":"Toledo","sequence":"additional","affiliation":[{"name":"Microsystems, Actuators and Sensors Group, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jorge","family":"Hernando-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Microsystems, Actuators and Sensors Group, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdallah","family":"Ababneh","sequence":"additional","affiliation":[{"name":"Electronic Engineering Department, Hijjawi Faculty for Engineering Technology, Yarmouk University, 21163 Irbid, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Helmut","family":"Seidel","sequence":"additional","affiliation":[{"name":"Chair of Micromechanics, Microfluidics\/Microactuators, Faculty of Natural Sciences and Technology II, Saarland University, 66123 Saarbr\u00fccken, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8605-0321","authenticated-orcid":false,"given":"Jos\u00e9 Luis","family":"S\u00e1nchez-Rojas","sequence":"additional","affiliation":[{"name":"Microsystems, Actuators and Sensors Group, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"291","DOI":"10.1016\/j.snb.2017.07.096","article-title":"Flow-through sensor based on piezoelectric MEMS resonator for the in-line monitoring of wine fermentation","volume":"254","author":"Toledo","year":"2018","journal-title":"Sens. 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