A Novel Silicon-Embedded Toroidal Power Inductor With Magnetic Core

Abstract

In this letter, a novel post-CMOS silicon-embedded toroidal power inductor with an MnZn ferrite composite core is proposed and demonstrated. The inductor is accommodated within the groove at the backside of a Si chip and connected to the front-side IC through vias for area saving, electromagnetic interference suppression, and large power-handling capability. A 2.9- <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\hbox{mm}^{2}$</tex></formula> embedded inductor with an inductance of 43.6 nH and a peak <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$Q$</tex></formula> -factor of 16.2 is fabricated. It achieves a saturation current of 10 A, making it promising for on-chip light-emitting diode driver applications.