{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T06:43:47Z","timestamp":1775803427326,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,1,23]],"date-time":"2015-01-23T00:00:00Z","timestamp":1421971200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a novel flexible piezoelectric micro-machined ultrasound transducer, which is based on PZT and a polyimide substrate. The transducer is made on the polyimide substrate and packaged with medical polydimethylsiloxane. Instead of etching the PZT ceramic, this paper proposes a method of putting diced PZT blocks into holes on the polyimide which are pre-etched. The device works in d31 mode and the electromechanical coupling factor is 22.25%. Its flexibility, good conformal contacting with skin surfaces and proper resonant frequency make the device suitable for heart imaging. The flexible packaging ultrasound transducer also has a good waterproof performance after hundreds of ultrasonic electric tests in water. It is a promising ultrasound transducer and will be an effective supplementary ultrasound imaging method in the practical applications.<\/jats:p>","DOI":"10.3390\/s150202538","type":"journal-article","created":{"date-parts":[[2015,1,23]],"date-time":"2015-01-23T11:20:34Z","timestamp":1422012034000},"page":"2538-2547","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":66,"title":["A Flexible Ultrasound Transducer Array with Micro-Machined Bulk PZT"],"prefix":"10.3390","volume":"15","author":[{"given":"Zhe","family":"Wang","sequence":"first","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Qing-Tang","family":"Xue","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Yuan-Quan","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Yi","family":"Shu","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"He","family":"Tian","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Yi","family":"Yang","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Dan","family":"Xie","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]},{"given":"Jian-Wen","family":"Luo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Tsinghua University, Beijing 100084, China"}]},{"given":"Tian-Ling","family":"Ren","sequence":"additional","affiliation":[{"name":"Institute of Microelectronics, Tsinghua University, Beijing 100084, China"},{"name":"Tsinghua National Laboratory for Information Science and Technology (TNList),  Beijing 100084, China"}]}],"member":"1968","published-online":{"date-parts":[[2015,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1016\/j.sna.2003.11.022","article-title":"Development of piezoelectric micromachined ultrasonic transducers","volume":"111","author":"Akasheh","year":"2004","journal-title":"Sens. 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