{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T02:47:16Z","timestamp":1775011636553,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,25]],"date-time":"2022-07-25T00:00:00Z","timestamp":1658707200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100019956","name":"Nanomedical Devices Development Project of NNFC","doi-asserted-by":"publisher","award":["1711160154"],"award-info":[{"award-number":["1711160154"]}],"id":[{"id":"10.13039\/501100019956","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019956","name":"Nanomedical Devices Development Project of NNFC","doi-asserted-by":"publisher","award":["2019R1A2C2002084"],"award-info":[{"award-number":["2019R1A2C2002084"]}],"id":[{"id":"10.13039\/501100019956","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019956","name":"Nanomedical Devices Development Project of NNFC","doi-asserted-by":"publisher","award":["2021M3F3A2A01037365"],"award-info":[{"award-number":["2021M3F3A2A01037365"]}],"id":[{"id":"10.13039\/501100019956","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019956","name":"Nanomedical Devices Development Project of NNFC","doi-asserted-by":"publisher","award":["202013B05"],"award-info":[{"award-number":["202013B05"]}],"id":[{"id":"10.13039\/501100019956","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["1711160154"],"award-info":[{"award-number":["1711160154"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["2019R1A2C2002084"],"award-info":[{"award-number":["2019R1A2C2002084"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["2021M3F3A2A01037365"],"award-info":[{"award-number":["2021M3F3A2A01037365"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["202013B05"],"award-info":[{"award-number":["202013B05"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Korea Medical Device Development Fund","award":["1711160154"],"award-info":[{"award-number":["1711160154"]}]},{"name":"Korea Medical Device Development Fund","award":["2019R1A2C2002084"],"award-info":[{"award-number":["2019R1A2C2002084"]}]},{"name":"Korea Medical Device Development Fund","award":["2021M3F3A2A01037365"],"award-info":[{"award-number":["2021M3F3A2A01037365"]}]},{"name":"Korea Medical Device Development Fund","award":["202013B05"],"award-info":[{"award-number":["202013B05"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>An acoustic matching layer is an essential component of an ultrasound transducer to achieve maximum ultrasound transmission efficiency. Here, we develop a flexible printed circuit board (FPCB) with a composite structure consisting of multiple polyimide and copper layers and demonstrate it as a novel acoustic matching layer. With a flexible substrate and robust ACF bonding, the FPCB not only serves as an acoustic matching layer between piezoelectric elements and the surrounding medium but also as a ground for the electrical connection between the transducer array elements and the folded substrate. A 1D linear ultrasound transducer array with the FPCB matching layer exhibits larger output pressure, wider -3dB bandwidth, and higher ultrasound beam intensity compared to that of an ultrasound transducer array with the alumina\/epoxy matching layer, which is one of the most commonly applied composite matching layers. The enhanced transmission performance verifies that the proposed FPCB is an excellent matching layer for 1D linear ultrasound transducer arrays.<\/jats:p>","DOI":"10.3390\/s22155557","type":"journal-article","created":{"date-parts":[[2022,7,26]],"date-time":"2022-07-26T00:17:27Z","timestamp":1658794647000},"page":"5557","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["FPCB as an Acoustic Matching Layer for 1D Linear Ultrasound Transducer Arrays"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8217-6752","authenticated-orcid":false,"given":"Taemin","family":"Lee","sequence":"first","affiliation":[{"name":"School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2604-2626","authenticated-orcid":false,"given":"Joontaek","family":"Jung","sequence":"additional","affiliation":[{"name":"Office of Nano Convergence Technology, National NanoFab Center, Daejeon 34141, Korea"}]},{"given":"Sang-Mok","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4606-0036","authenticated-orcid":false,"given":"Jongcheol","family":"Park","sequence":"additional","affiliation":[{"name":"Office of Nano Convergence Technology, National NanoFab Center, Daejeon 34141, Korea"}]},{"given":"Jae-Hyeong","family":"Park","sequence":"additional","affiliation":[{"name":"Samsung Foundry, Samsung Electronics Co., Ltd., Hwaseong 18448, Korea"}]},{"given":"Kyung-Wook","family":"Paik","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea"}]},{"given":"Hyunjoo J.","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1007\/s13534-017-0021-8","article-title":"Ultrasonic transducers for medical diagnostic imaging","volume":"7","author":"Lee","year":"2017","journal-title":"Biomed. 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