High Q CoFeSiB/SiO_2 Composite Multilayer Film

摘要

In recent advanced high frequency electro-magnetic devices, such as portable telephones and multifunctional devices, both high efficiency and downsizing are required. For this purpose, more highly efficient micro DC/DC convertors and resultant high quality micro inductors for use at high frequencies have been developed. The following factors for energy-saving have been targeted: micro size, small area, short process, cost efficiency and high quality. However, with the downsizing of such devices, their operating frequencies have been increased, resulting in a serious problem, namely, increased magnetic core loss. To overcome this, high quality and high inductance are required for thin film inductors employing thin film soft magnetic materials which are smaller in size and have a higher frequency material than ferrite.