Patent ID: 8749054
Filing Date: 2014-06-10
Classification: H01F,H01L,H02M,Y10T

Abstract:
1. A monolithic power management module, comprising: a first electrode; a semiconductor layer disposed upon the first electrode; a vertical power FET formed in the semiconductor layer to modulate currents through the semiconductor layer; the FET having a second electrode disposed upon a surface of the semiconductor layer opposing the first electrode, and an insulated gate electrode inserted between the semiconductor layer and the first electrode; and a toroidal inductor with a ceramic magnetic core formed on the semiconductor layer around the FET and the inductor having a first winding around the core and connected to the FET second electrode; wherein windings of the toroidal inductor coil are in contact with an adjacent dielectric and comprise thin layers of electrical conductivity material that envelopes a mechanical constraining member including a low-expansion elemental metal having a measured hardness greater than 2× the measured hardness of the electrical conductivity material and a coefficient of thermal expansion that is within 25% of the coefficient of thermal expansion of the adjacent dielectric; and wherein the power FET includes an elongated gate electrode comprising a conductor that forms a resonant transmission line by configuring the conductor to form a serpentine electrode that contains a capacitive element determined by the charge collected beneath the gate, a resistive element determined by the conductor, length and cross-sectional area of the conductor used to form the serpentine gate electrode, and an inductive element formed by the half-turns that loop the serpentine winding back upon itself.