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 μH and peak quality factors of 15.1 at 8.3 MHz.