{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T03:50:32Z","timestamp":1763178632349,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2010,8,31]],"date-time":"2010-08-31T00:00:00Z","timestamp":1283212800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>An on-chip transformer with a ferrofluid magnetic core has been developed and tested. The transformer consists of solenoid-type coil and a magnetic core of ferrofluid, with the former fabricated by MEMS technology and the latter by a chemical co-precipitation method. The performance of the MEMS transformer with a ferrofluid magnetic core was measured and simulated with frequencies ranging from 100 kHz to 100 MHz. Experimental results reveal that the presence of the ferrofluid increases the inductance of coils and the coupling coefficient of transformer; however, it also increases the resistance owing to the lag between the external magnetic field and the magnetization of the material.<\/jats:p>","DOI":"10.3390\/s100908161","type":"journal-article","created":{"date-parts":[[2010,9,19]],"date-time":"2010-09-19T09:41:46Z","timestamp":1284889306000},"page":"8161-8172","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Applications of Ferro-Nanofluid on a Micro-Transformer"],"prefix":"10.3390","volume":"10","author":[{"given":"Tsung-Han","family":"Tsai","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan"}]},{"given":"Long-Sheng","family":"Kuo","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8073-9344","authenticated-orcid":false,"given":"Ping-Hei","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan"}]},{"given":"Da-sheng","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Energy and Refrigerating Air-conditioning Engineering, National Taipei University of Technology, No.1, Sec. 3, Chung-hsiao E. Rd., Taipei 10608, Taiwan"}]},{"given":"Chin-Ting","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Computer-Aided Engineering, St. John\u2019s University, No. 499, Sec. 4, Tam-king Rd., Tamsui, Taipei 25135, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2010,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1369","DOI":"10.1109\/20.706551","article-title":"A microfabricated transformer for high-frequency power or signal conversion","volume":"34","author":"Xu","year":"1998","journal-title":"IEEE Trans. Magn"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"7081","DOI":"10.1143\/JJAP.37.7081","article-title":"Monolithic fabrication of electroplated solenoid inductors using three-dimensional photolithography of a thick photoresist","volume":"37","author":"Yoon","year":"1998","journal-title":"Jpn. J. Appl. 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