{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T22:18:53Z","timestamp":1772230733639,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,2,29]],"date-time":"2020-02-29T00:00:00Z","timestamp":1582934400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program of China","award":["No.2018YFB2002500"],"award-info":[{"award-number":["No.2018YFB2002500"]}]},{"name":"Zhejiang Province Key R &amp; D programs","award":["No.2018C01037"],"award-info":[{"award-number":["No.2018C01037"]}]},{"name":"Zhejiang Lab","award":["No.2018EB0ZX01"],"award-info":[{"award-number":["No.2018EB0ZX01"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No.61801158"],"award-info":[{"award-number":["No.61801158"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No.21703204"],"award-info":[{"award-number":["No.21703204"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper reports a novel flexible film bulk acoustic resonator (FBAR) based on    \u03b2   -phase polyvinylidene fluoride (PVDF) piezoelectric polymer. The proposed device was simulated and evaluated; then, a low-temperature photolithography process with a double exposure method was developed to pattern the electrodes for the device, which enabled the device to retain the piezoelectric properties of the    \u03b2   -phase PVDF film. Results showed that the \u03b2-phase PVDF FBARs had a resonant frequency round 9.212     MHz     with a high electromechanical coupling coefficient (     k 2     ) of 12.76% \u00b1 0.56%. The device performed well over a wide bending-strain range up to 2400      \u03bc \u03b5      owing to its excellent flexibility. It showed good stability as a strain sensor with a sensitivity of 80     Hz \/  \u03bc \u03b5     , and no visible deterioration was observed after cyclic bending tests. The PVDF FBAR also exhibited an exceptionally large temperature coefficient of frequency (TCF) of \u22124630     ppm \/ K    , two orders of magnitude larger than those of other FBARs based on common inorganic piezoelectric materials, extraordinarily high sensitivity for temperature sensing. All results showed that    \u03b2   -phase PVDF FBARs have the potential to expand the application scope for future flexible electronics.<\/jats:p>","DOI":"10.3390\/s20051346","type":"journal-article","created":{"date-parts":[[2020,3,3]],"date-time":"2020-03-03T03:13:28Z","timestamp":1583205208000},"page":"1346","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["A Flexible Film Bulk Acoustic Resonator Based on \u03b2-Phase Polyvinylidene Fluoride Polymer"],"prefix":"10.3390","volume":"20","author":[{"given":"Ting","family":"Wu","sequence":"first","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9798-5149","authenticated-orcid":false,"given":"Hao","family":"Jin","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"},{"name":"ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8715-7072","authenticated-orcid":false,"given":"Shurong","family":"Dong","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"},{"name":"ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China"}]},{"given":"Weipeng","family":"Xuan","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China"}]},{"given":"Hongsheng","family":"Xu","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Leihe","family":"Lu","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Zijing","family":"Fang","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Shuyi","family":"Huang","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Xiang","family":"Tao","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Lin","family":"Shi","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Shuting","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"}]},{"given":"Jikui","family":"Luo","sequence":"additional","affiliation":[{"name":"Key Lab. of Advanced Micro\/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China"},{"name":"ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China"},{"name":"Ministry of Education Key Laboratory of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,29]]},"reference":[{"key":"ref_1","unstructured":"William, W., and Salleo, A. 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