{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T05:16:25Z","timestamp":1788412585166,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2025M771382"],"award-info":[{"award-number":["2025M771382"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2025M771382"],"award-info":[{"award-number":["2025M771382"]}],"id":[{"id":"https:\/\/ror.org\/0426zh255","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"crossref","award":["2042026kf0041"],"award-info":[{"award-number":["2042026kf0041"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Lamb wave devices have the advantage of monolithic multi-frequency integration and show great application potential in mobile communications. However, their performance is often limited by spurious modes. In this work, an arc-shaped apodization electrode structure is proposed to suppress spurious modes in Sc0.2Al0.8N Lamb wave resonators (LWRs). By shortening the overlap length of the interdigital transducer electrodes at the edges, the energy coupling in the spurious-mode regions is reduced while the main-mode region is largely preserved. Finite element method (FEM) simulations confirm the suppression of spurious responses near the anti-resonant frequency. Based on the optimized design, typical and arc-shaped apodization LWRs and filters were fabricated. The fabricated arc-shaped apodization LWR exhibits an effective electromechanical coupling coefficient (keff2) of 3.9%. The corresponding filter operates at a center frequency of 1.774 GHz, with a \u22123 dB bandwidth of 20 MHz and a minimum insertion loss of 4.50 dB. Compared with the typical filter fabricated on the same wafer, the insertion loss is reduced by 1.22 dB. These results demonstrate the effectiveness of the proposed electrode apodization scheme for suppressing spurious modes in Sc0.2Al0.8N Lamb wave devices.<\/jats:p>","DOI":"10.3390\/mi17091046","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:32:18Z","timestamp":1788258738000},"page":"1046","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Spurious-Mode Suppression in Sc0.2Al0.8N Film Lamb Wave Resonators and Filters with Arc-Shaped Apodization"],"prefix":"10.3390","volume":"17","author":[{"given":"Kai","family":"Cai","sequence":"first","affiliation":[{"name":"School of Mathematics and Computer Sciences, Nanchang University, No. 999 of Xuefu Road, Nanchang 330031, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3456-2274","authenticated-orcid":false,"given":"Haiyang","family":"Li","sequence":"additional","affiliation":[{"name":"Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, School of Integrated Circuits, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tingting","family":"Yang","sequence":"additional","affiliation":[{"name":"Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, School of Integrated Circuits, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qinwen","family":"Xu","sequence":"additional","affiliation":[{"name":"Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, School of Integrated Circuits, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0555-5745","authenticated-orcid":false,"given":"Yao","family":"Cai","sequence":"additional","affiliation":[{"name":"Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, School of Integrated Circuits, Wuhan University, Wuhan 430072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Xiang, W., Zheng, K., and Shen, X. 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Proceedings of the 2022 IEEE International Ultrasonics Symposium (IUS), IEEE.","DOI":"10.1109\/IUS54386.2022.9958311"}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/9\/1046\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T04:34:11Z","timestamp":1788410051000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/9\/1046"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,1]]},"references-count":37,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["mi17091046"],"URL":"https:\/\/doi.org\/10.3390\/mi17091046","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,1]]}}}