2D thin film cores are first to feature wafer level magnetics technology

Fully qualified for full scale mass production in a high volume foundry, the wafer level magnetics (WLM) technology is aimed at taking magnetic components from their 3d discrete shape to a planar 2d thin film that can be deposited with standard wafer processes on top of cmos wafers. Developed with a view to achieving monolithic power SocS, Enpirion says the 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 utilising electroplated WLM materials that can be post cmos processed," said Enpirion's director of MEMS technology, Dr Trifon Liakopoulos. "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. With wafer electroplating methods, it is possible to cost effectively deposit photo lithographically defined FCA magnetic cores on silicon wafers." According to Dr Liakopoulos, the FCA module has high resistivity, low coercivity and maintains high effective permeability at frequencies higher than 20MHz. It also has a high magnetic saturation, making it suitable for use as single or multiple layers in power circuits.