화학공학소재연구정보센터
Solid-State Electronics, Vol.51, No.3, 405-413, 2007
Integrated RF inductors with micro-patterned NiFe core
Integrated radio-frequency solenoids with micro-patterned magnetic cores for reduced dimensions and compatibility with CMOS/ BiCMOS process technology are presented and discussed. It is demonstrated that the use of a ferromagnetic (FM) core leads to a more than 20-fold enhanced inductance per area. This is achieved by tailoring the anisotropy of the FM core and the design of the metal coil structure. Both a higher operating frequency and a larger inductance are obtained by increasing the shape aspect ratio of the FM core and by depositing the magnetic film under an external magnetic field. A reference to an optimum shape anisotropy has been created by measuring the FM core inductors with an external DC magnetic field. An optimum practical trade-off of inductance and operating frequency results from patterning of the FM core. (C) 2007 Elsevier Ltd. All rights reserved.