Title :
Thin-film inductor for gigahertz band with CoFeSiO-SiO2 multilayer granular films and its application for power amplifier module
Author :
Ikeda, K. ; Kobayashi, K. ; Ohta, K. ; Kondo, R. ; Suzuki, T. ; Fujimoto, M.
Author_Institution :
R&D Center, Taiyo Yuden Co. Ltd., Gunma, Japan
Abstract :
The thin-film power amplifier module for wide-band code division multiple access was designed and fabricated using the magnetic thin film as magnetic core of choke inductors. CoFeSiO-SiO2 multilayer granular films showing high resistivity and good magnetic properties were applied to the module. Inductance value increased about 30% by application of magnetic films, and occupation area and series resistance were also reduced by 20%. The obtained module size was 3.0 mm × 3.5 mm, which was much smaller than the conventional power amplifier module, since the bias circuit was formed on the same silicon substrate.
Keywords :
MMIC power amplifiers; cobalt compounds; code division multiple access; electrical resistivity; granular materials; iron compounds; magnetic cores; magnetic multilayers; magnetic thin film devices; microwave materials; modules; silicon compounds; thin film inductors; 3.0 mm; 3.5 mm; CoFeSiO-SiO2; CoFeSiO-SiO2 multilayer granular films; Si; bias circuit; choke inductors; gigahertz band; high resistivity; magnetic core; magnetic properties; magnetic thin film; module size; occupation area; power amplifier module; series resistance; silicon substrate; thin-film inductor; wide-band code division multiple access; Broadband amplifiers; Conductivity; Inductance; Magnetic cores; Magnetic films; Magnetic multilayers; Magnetic properties; Multiaccess communication; Power amplifiers; Thin film inductors;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.815893
