{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T23:36:06Z","timestamp":1781652966167,"version":"3.54.5"},"reference-count":50,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2020,8,4]],"date-time":"2020-08-04T00:00:00Z","timestamp":1596499200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MTEC Global Co.","award":["OSP196189"],"award-info":[{"award-number":["OSP196189"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Piezoelectric micromachined ultrasound transducers (PMUT) incorporating lead zirconate titanate PbZr0.52Ti0.48O3 (PZT) thin films were investigated for miniaturized high-frequency ultrasound systems. A recently developed process to remove a PMUT from an underlying silicon (Si) substrate has enabled curved arrays to be readily formed. This research aimed to improve the design of flexible PMUT arrays using PZFlex, a finite element method software package. A 10 MHz PMUT 2D array working in 3-1 mode was designed. A circular unit-cell was structured from the top, with concentric layers of platinum (Pt)\/PZT\/Pt\/titanium (Ti) on a polyimide (PI) substrate. Pulse-echo and spectral response analyses predicted a center frequency of 10 MHz and bandwidth of 87% under water load and air backing. A 2D array, consisting of the 256 (16 \u00d7 16) unit-cells, was created and characterized in terms of pulse-echo and spectral responses, surface displacement profiles, crosstalk, and beam profiles. The 2D array showed: decreased bandwidth due to protracted oscillation decay and guided wave effects; mechanical focal length at 2.9 mm; 3.7 mm depth of field for -6 dB; and -55.6 dB crosstalk. Finite element-based virtual prototyping identified figures of merit\u2014center frequency, bandwidth, depth of field, and crosstalk\u2014that could be optimized to design robust, flexible PMUT arrays.<\/jats:p>","DOI":"10.3390\/s20154335","type":"journal-article","created":{"date-parts":[[2020,8,4]],"date-time":"2020-08-04T05:56:46Z","timestamp":1596520606000},"page":"4335","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["10 MHz Thin-Film PZT-Based Flexible PMUT Array: Finite Element Design and Characterization"],"prefix":"10.3390","volume":"20","author":[{"given":"Jeong Nyeon","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianning","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas N.","family":"Jackson","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyusun","family":"Choi","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7267-9281","authenticated-orcid":false,"given":"Susan","family":"Trolier-McKinstry","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard L.","family":"Tutwiler","sequence":"additional","affiliation":[{"name":"Applied Research Laboratory, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judith A.","family":"Todd","sequence":"additional","affiliation":[{"name":"Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Mina, I.G., Kim, H., Kim, I., Park, S.K., Choi, K., Jackson, T.N., Tutwiler, R.L., and Trolier-McKinstry, S. 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