{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T00:18:04Z","timestamp":1782951484838,"version":"3.54.5"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,2]],"date-time":"2018-08-02T00:00:00Z","timestamp":1533168000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003693","name":"Korea Institute of Science and Technology","doi-asserted-by":"publisher","award":["2E27910"],"award-info":[{"award-number":["2E27910"]}],"id":[{"id":"10.13039\/501100003693","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R01HL117740"],"award-info":[{"award-number":["R01HL117740"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Capacitive micromachined ultrasonic transducers (CMUTs) with substrate-embedded springs offer highly efficient output pressure performance over conventional CMUTs, owing to their nonflexural parallel plate movement. The embedded silicon springs support thick Si piston plates, creating a large nonflexural average volume displacement efficiency in the operating frequency range from 1\u20133 MHz. Static and dynamic volume displacements of the nonflexural parallel plates were examined using white light interferometry and laser Doppler vibrometry. In addition, an output pressure measurement in immersion was performed using a hydrophone. The device showed a maximum transmission efficiency of 21 kPa\/V, and an average volume displacement efficiency of 1.1 nm\/V at 1.85 MHz with a low DC bias voltage of 55 V. The device element outperformed the lead zirconate titanate (PZT) ceramic HD3203, in the maximum transmission efficiency or the average volume displacement efficiency by 1.35 times. Furthermore, its average volume displacement efficiency reached almost 80% of the ideal state-of-the-art single-crystal relaxor ferroelectric materials PMN-0.33PT. Additionally, we confirmed that high-efficiency output pressure could be generated from the CMUT device, by quantitatively comparing the hydrophone measurement of a commercial PZT transducer.<\/jats:p>","DOI":"10.3390\/s18082520","type":"journal-article","created":{"date-parts":[[2018,8,3]],"date-time":"2018-08-03T03:03:15Z","timestamp":1533265395000},"page":"2520","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["High-Efficiency Output Pressure Performance Using Capacitive Micromachined Ultrasonic Transducers with Substrate-Embedded Springs"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7702-716X","authenticated-orcid":false,"given":"Byung Chul","family":"Lee","sequence":"first","affiliation":[{"name":"Center for BioMicrosystems, Korea Institute of Science and Technology, Seoul 02792, Korea"},{"name":"Department of Biomedical Engineering, University of Science and Technology, Daejeon 34113, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amin","family":"Nikoozadeh","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Stanford University, CA 94305, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5117-5853","authenticated-orcid":false,"given":"Kwan Kyu","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Butrus T.","family":"Khuri-Yakub","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Stanford University, CA 94305, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1109\/MSPEC.2009.4907385","article-title":"Next-gen ultrasound","volume":"46","author":"Oralkan","year":"2009","journal-title":"IEEE Spectr."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"796","DOI":"10.1109\/TBCAS.2014.2298197","article-title":"Integrated circuits for volumetric ultrasound imaging with 2-D CMUT arrays","volume":"7","author":"Bhuyan","year":"2013","journal-title":"IEEE Trans. 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