{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,12]],"date-time":"2026-07-12T06:29:04Z","timestamp":1783837744406,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,6,14]],"date-time":"2017-06-14T00:00:00Z","timestamp":1497398400000},"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>A square piezoelectric composite diaphragm was analyzed by the finite element method to enhance the sensitivity of a piezoelectric micromachined ultrasound transducer (pMUT). The structures of electrode and piezoelectric film were optimized and a centric electrode was designed to avoid the counteraction of stress in the centre and edges. In order to further improve the sensitivity; a pMUT with partially-etched piezoelectric film was adopted. The receive and transmit sensitivities of the pMUT were analyzed in details. The receive sensitivity of pMUT with partially-etched ZnO film is 3.3 dB or 6.8 dB higher than those with a centric and whole electrode, respectively; and the amplitude of a partially-etched ZnO film pMUT under a certain voltage is 5.5 dB and 30 dB higher than those with centric and whole electrode separately. Two pMUT-based ZnO films were fabricated by micromachining technology and their receive and transmit sensitivities were tested. The ZnO films deposited by direct current (DC) magnetron sputtering exhibit a densely packed structure with columnar crystallites. The test results show that the structure of the square diaphragm with partially-etched piezoelectric layer can significantly improve the transducer sensitivity. The receive sensitivity and transmit sensitivity are \u2212238.35 dB (ref. 1 V\/\u03bcPa) and 150.42 dB (ref. 1 \u03bcPa\/V); respectively.<\/jats:p>","DOI":"10.3390\/s17061381","type":"journal-article","created":{"date-parts":[[2017,6,14]],"date-time":"2017-06-14T10:49:53Z","timestamp":1497437393000},"page":"1381","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Design and Fabrication of Piezoelectric Micromachined Ultrasound Transducer (pMUT) with Partially-Etched ZnO Film"],"prefix":"10.3390","volume":"17","author":[{"given":"Junhong","family":"Li","sequence":"first","affiliation":[{"name":"State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Science, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Ren","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Science, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guoxiang","family":"Fan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Science, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chenghao","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Science, Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1470","DOI":"10.1109\/TUFFC.2010.1566","article-title":"Fabrication of High-Frequency pMUT Arrays on Silicon Substrates","volume":"57","author":"Pedersen","year":"2010","journal-title":"IEEE Trans. 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