High-frequency magnetic properties of FeCoBSi/SiO/sub 2/ and (FeCo/CoB)/SiO/sub 2/ multilayer thin films

Applications of soft magnetic magnetostrictive thin films in high-frequency devices such as inductors, transmission lines, or stress sensors require low magnetic losses. Samples of about 2-(mu)m thick FeCoBSi/SiO/sub 2/ and (FeCo/CoB)/SiO/sub 2/ multilayers with varying SiO/sub 2/ thickness between 10 and 100 nm have been fabricated. The magnetic properties of these samples have been characterized by vibrating sample magnetometry. Impedance measurements in the kilohertz to megahertz range and permeameter measurements up to 8 GHz were carried out to determine the high-frequency behavior. The measurements showed an improvement in the quality factor of the films due to the dielectric lamination.