title: Applications of ferro-nanofluid on a micro-transformer.
abstract: 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.
authors.affiliation: Department of Mechanical Engineering, National Taiwan University, No 1, Sec 4, Roosevelt Rd, Taipei 10617, Taiwan. f91522531@ntu.edu.tw
authors.forename: Tsung-Han
authors.initials: TH
authors.lastname: Tsai
authors.forename: Long-Sheng
authors.initials: LS
authors.lastname: Kuo
authors.forename: Ping-Hei
authors.initials: PH
authors.lastname: Chen
authors.forename: Da-Sheng
authors.initials: DS
authors.lastname: Lee
authors.forename: Chin-Ting
authors.initials: CT
authors.lastname: Yang
mesh_terms: D004553:Electric Conductivity; D004574:Electromagnetic Fields; D004867:Equipment Design; D005290:Ferric Compounds / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D055616:Microtechnology / Q000295:instrumentation*; D036103:Nanotechnology / Q000295:instrumentation; D009821:Oils / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D009821:Oils; D013501:Surface-Active Agents; C000499:ferric oxide