Measured performance and micro-fabrication of racetrack power inductors

This paper presents micro-fabrication results and electrical performance measurements for chip-scale racetrack power inductors. Magnetic components with sputtered Co-Zr-O magnetic cores are demonstrated in a multi-megahertz dc-dc converter for solid-state lighting applications. The dc-dc converter achieves an 89% conversion efficiency at 5 MHz with an inductor power density of 1 W/mm(2) of substrate area. Small-signal measurements of the inductors are compared with modeled predictions to validate the design optimization approach. Fabricated components achieved inductance values of 1.2 mu H and peak quality factors of 15.1 at 8.3 MHz.