Integration of magnetic materials into package RF and power inductors on organic substrates for system in package (SiP) applications

In this paper, soft ferromagnetic materials were deposited on organic packaging substrates to explore their potential applications in in-package inductors. Amorphous cobalt alloy, Co-Zr-Ta-B, was chosen due to its high saturation magnetization, low coercivity and small magnetostriction. As-deposited films were characterized by vibrating sample magnetometer (VSM) showing comparable magnetic properties in comparison to the films on quartz and silicon wafers. Stripline and spiral inductors with Co-Zr-Ta-B films were fabricated on package substrates to explore their potential in-package RF and power inductor applications.