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PrFET energy transduction is capable of detecting acoustic signals by adopting an acoustically responsive sensing structure. However, it has not been investigated whether PrFET acoustic sensors can exhibit signal-response characteristics that differ from those previously reported. To investigate whether the sensor response could be enhanced at a specific frequency, this study adopted a sector-shaped cantilever diaphragm. The sector-shaped cantilever has a free end at the center, allowing for greater stress to be induced in the piezoresistive channel under acoustic excitation. The acousto-mechanical response of the proposed structure was characterized in terms of its displacement under acoustic excitation and the resulting stress induced in the PrFET at the support. A PrFET acoustic sensor incorporating the designed diaphragm was then fabricated, and the sensitivity enhancement and the formation of a specific resonance frequency was experimentally validated.<\/jats:p>","DOI":"10.3390\/s26196274","type":"journal-article","created":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T10:57:46Z","timestamp":1791197866000},"page":"6274","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Study on a Sector-Shaped Cantilever Diaphragm for Frequency-Response Improvement of an Acoustic Sensor Based on Piezoresistive Effect in MOSFET"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7645-7010","authenticated-orcid":false,"given":"Chayeong","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang-si 37673, Republic of Korea"},{"name":"Construction Equipment Technology Center, Advanced Mobility & Robot System Group, Korea Institute of Industrial Technology (KITECH), Gyeongsan-si 38408, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-0637-1906","authenticated-orcid":false,"given":"Eunsik","family":"Noh","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang-si 37673, Republic of Korea"},{"name":"Construction Equipment Technology Center, Advanced Mobility & Robot System Group, Korea Institute of Industrial Technology (KITECH), Gyeongsan-si 38408, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Wonkyu","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang-si 37673, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-8577-6905","authenticated-orcid":false,"given":"Kumjae","family":"Shin","sequence":"additional","affiliation":[{"name":"Construction Equipment Technology Center, Advanced Mobility & Robot System Group, Korea Institute of Industrial Technology (KITECH), Gyeongsan-si 38408, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Szymoniak, S., and Kuczy\u0144ski, \u0141. 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