Planar Power Inductor with Magnetic Film for Embedded LSI Package

Abstract

A power inductor component is relatively very thick and large shape. Therefore, these components are not appropriate feature to be embedded into a LSI package and mounted nearby a LSI chip, it is challengeable to make the embedded application. However, LSI power delivery system is going for low voltage and large current, and losses between power supply and loads impacts on the power supply efficiency characteristic. In order to solve this problem, miniaturization for a power inductor is needed to realize the embedded applications. As one of approaches to realize the power delivery systems, the planar power inductor with Zn-Ferrite film has been studied for the next generations. A structure of planar power inductor was designed to be configured 2-turn inner copper spiral coil covered with top and bottom magnetic core. The Zn-Ferrite film used as a magnetic core has a high resonance frequency around 300MHz and high saturation magnetization of 0.6T or more, and this film can be formed in low temperature, which can be handled in parallel way to fabricate an organic package. We have developed the organic package with employing the power inductors covered with Zn-Ferrite as prototype of the embedded application, and evaluated the electrical and magnetic characterizations. The thickness of embedded planar power inductor covered with Zn-ferrite film is 50um, and the size is 850um squares. Q factor is 10 to 13 in 30MHz to 100MHz. The degradation of inductance caused by the superimposed current does not happen without changing until 3A.

Atomically flat nickel film grown on synthetic mica

“…Recently, a synthetic mica of fluorophlogopite [KMg 3 -(AlSi 3 O 10 )F 2 ] has been used as a substrate of hetero (van der Waals) epitaxy given its atomically smooth surface, chemically inertness, and thermally stability even at a temperature of 1000 °C. [25][26][27] In the present paper, the successful growth of atomically flat Ni(111) films on a synthetic mica substrate is described.…”

Embedded Planar Power Inductor in an Organic Interposer for Package-Level DC Power Grid

“…The POL converter will have an embedded power magnetics in a package, semiconductor switches, and control circuit. To realize the embedded power magnetics, we have developed a Zn-Fe ferrite planar spiral inductor [5], [6] embedded in an organic interposer. In addition, we have developed a carbonyl-iron/epoxy composite core planar spiral inductor as an on-package power magnetics [4].…”