Integrated Magnetic Inductor Technology on Silicon

This work presents a CMOS back-end-of-line (BEOL) compatible thin-film magnetic inductor technology to realize fully integrated on-chip power conversion. The conventional way of realizing on-chip inductors results in poor inductance density. The utilization of magnetic core helped to boost the inductance. The measured electrical performance confirms that a high inductance density of 140 nH/mm
²
can be achieved, which is 30 times more than its air-core counterparts. Due to the inductance boost, large value inductance can be realized without sacrificing its DC resistance, and the inductance to DC resistance ratio reaches up to 320 nH/Ohm. These values translate into more than 95% inductor efficiency, and eventually, it will facilitate to realize fully integrated, high efficiency, Power Supply On-Chip (PwrSoC).