Integrated circuit spiral inductor

摘要

High quality factor (Q) spiral and toroidal inductor and transformer are disclosed that are compatible with silicon very large scale integration (VLSI) processing, consume a small IC area, and operate at high frequencies. The spiral inductor has a spiral metal coil deposited in a trench formed in a dielectric layer over a substrate. The metal coil is enclosed in ferromagnetic liner and cap layers, and is connected to an underpass contact through a metal filled via in the dielectric layer. The spiral inductor also includes ferromagnetic cores lines surrounded by the metal spiral coil. A spiral transformer is formed by vertically stacking two spiral inductors, or placing them side-by-side over a ferromagnetic bridge formed below the metal coils and cores lines. The toroidal inductor includes a toroidal metal coil with a core having ferromagnetic strips. The toroidal metal coil is segmented into two coils each having a pair of ports to form a toroidal transformer.