Enpirion, Inc. has developed a new magnetic alloy, which enables the miniaturization of passive magnetic components and their assimilation with integrated circuits at wafer level. So-called wafer level magnetics (WLM) present a leap in traditional technology, which will take magnetic components from their 3-dimensional discrete shape to a planar 2-dimensional thin-film form that can be deposited with standard wafer processes on top of CMOS wafers.
Enpirion developed a turnkey process module, which features low cost of ownership plating equipment to deposit FCA on 6 inch or 8 inch wafers. The technology has been successfully transferred and embedded in a volume wafer production facility earlier this year, where Enpirion is producing the world's lowest cost, noise sensitive, low power POL dc-dc converters, the 1 Amp EL711 and the 1,5 Amp EL712, the industry's first Power System-on-Chips based on electroplated wafer level magnetics.
Enpirion's WLM technology is fully qualified for full-scale mass production in a high volume foundry and enables the industry's first ever Power System-on-Chips based on electroplated wafer level magnetics. Developed with a view to achieving monolithic Power System-on-Chips, the WLM technology can be easily transferred to other micro-magnetic applications, for example micro-transformers for signal isolation, micro-electromagnets for life sciences, integrated magnetic sensors for navigation and PMICs for portable consumer applications.
"Increasing the switching frequency allows the use of smaller inductors utilizing electroplated WLM materials that can be post-CMOS processed. We developed an amorphous Fe-Co based alloy called FCA, which is capable of operating at frequencies higher than 20MHz with minimal attenuation of magnetic properties," explains Dr. Trifon Liakopoulos, Director of MEMS technology and Enpirion's co-founder. "With wafer electroplating methods, it is possible to cost-effectively deposit photo-lithographically defined FCA magnetic cores on silicon wafers."
FCA has high resistivity, low coercivity and maintains high effective permeability at frequencies higher than 20MHz. FCA's high magnetic saturation makes it suitable for use as single or multiple layers in power circuits, where it is compatible with flip-chip, wire-bonding and solder re-flow packaging methods.
