Title :
Application of nanocrystalline Fe(or Co-Fe)-Hf-O magnetic films with high electrical resistivity to micro DC-DC converters
Author :
Sato, Toshiro ; Komai, Eiichi ; Yamasawa, Kiyohito ; Hatanai, Takashi ; Makino, Akihiro
Author_Institution :
Fac. of Eng., Shinshu Univ., Nagano, Japan
fDate :
9/1/1997 12:00:00 AM
Abstract :
High resistivity magnetic films, such as reactive sputtered Fe-Hf-O and Co-Fe-Hf-O, were applied to multilayered micro reactors for high frequency operation dc-dc converters. For a comparison, an amorphous Co-Ta-Hf film with good soft magnetic properties was also investigated. The micro reactor had the highest quality factor (the lowest loss) when using Co-Fe-Hf-O film with the highest resistivity. In 5 MHz operation of dc-dc converters using these micro reactors, the highest conversion efficiency was obtained when using Co-Fe-Hf-O film
Keywords :
DC-DC power convertors; cobalt compounds; electrical resistivity; hafnium compounds; iron compounds; magnetic multilayers; magnetic thin films; nanostructured materials; soft magnetic materials; sputtered coatings; 5 MHz; Co-Fe-Hf-O; DC-DC converter; Fe-Hf-O; conversion efficiency; electrical resistivity; high frequency operation; loss; multilayered micro reactor; nanocrystalline magnetic film; quality factor; reactive sputtering; soft magnetic properties; Amorphous materials; Coils; Conductivity; DC-DC power converters; Electric resistance; Frequency conversion; Inductors; Magnetic films; Magnetic properties; Magnetization; Permeability; Polyimides; Q factor;
Journal_Title :
Magnetics, IEEE Transactions on
