The large demand for fabrication of magnetic-based microsystems such as on-chip DC/DC power converters can be satisfied using microinductors as basic magnetic components.In this paper,a scheme of encapsulated spiral microinductors is described using a fully integratable post-CMOS fabrication process.The microinductor is composed of a copper spiral conductor sandwiched between two layers of a magnetic alloy,as shown in Fig.1.This structure is placed on top of a silicon wafer that already contains the power CMOS electronic circuits.Via openings in the bottom magnetic layer allow connection between the CMOS power circuit and the micromagnetic components.The thick electroplated Cu spiral windings have low resistance and are suitable for high power applications.
展开▼
