Micro-fabricated thin-film inductors for on-chip power conversion

Conference: CIPS 2012 - 7th International Conference on Integrated Power Electronics Systems
03/06/2012 - 03/08/2012 at Nuremberg, Germany

Proceedings: CIPS 2012

Pages: 6Language: englishTyp: PDF

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Authors:
Harburg, Daniel V.; Levey, Christopher G.; Sullivan, Charles R. (Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, USA 03755)
Yu, Xuehong; Herrault, Florian; Allen, Mark G. (School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA 30332)

Abstract:
This paper reports an optimized design and micro-fabrication approach for silicon-integrated elongated-spiral inductors for on-chip power conversion. The inductors are designed for high-power-density and high-efficiency DC-DC converters which transfer 25 W of power at frequencies between 5 and 30 MHz. The predicted power density of the inductors is close to 1 W/mm2 with predicted overall converter efficiencies exceeding 90%. A Co-Zr-O multilayer thin-film magnetic material surrounds the planar copper windings of the inductor within etched silicon trenches. Materials and most processing steps have been experimentally verified. The miniaturization and integration of high-efficiency inductors on silicon can enable radical reductions in the size and cost of power converters for a myriad of applications.