WINCHESTER TECHNOLOGIES LLC STTR Phase II Award, September 2023

State-of-the-art power electronics use discrete components such as power magnetic inductors and transformers operating at < 1MHz, which suffer from a large SWAP-C (size, weight, power consumption, and cost). It has been challenging to achieve simultaneously high inductance, compact size, and high quality factors at 1~300MHz for integrated power electronics. In the completed Phase II Army STTR Phase II project on Topic A16-020, “Low-Loss Commercial Deposition Technology for Thick Ferrite and Ferrite/Insulator Film on Printed Circuit Boards” (09/28/2018 ~ 09/27/2020), we have successfully demonstrated (1) a new custom-made spin-spray deposition system for depositing on 24” diameter large-scale PCB; (2) High-quality low-loss thick ferrite film deposition on large-scale thin (100µm) PCB panels (12” × 12”) with a high relative permeability of over 3000; compact HF (30~300MHz) coil antennas and UHF (300~3000MHz) patch antennas on ferrite coated PCBs which show significantly size miniaturization, enhanced radiation efficiency, enhanced bandwidth, and enhanced impedance matching. Based on the completed Phase II project, we propose this Sequential Phase II project to (1) tailor the spin spray deposited ferrites for integrated power inductors and transformers; and (2) develop integrated magnetic inductors and transformers with our low-loss spin-spray ferrite films on PCBs for power supply in package (PwrSiP) for 1~30MHz, and on Si substrates for power supply on chip (PwrSoC) for 30~300 MHz for modernizing integrated power electronics with ultra-low SWAP-C. The innovations of this Sequential Phase II project include (I) Spin-spray deposited thick ferrites are the only low-cost synthesis process at a low temperature of 90°C for integration on Si and PCBs; (II) the project team is the only one in the US having a successful demonstration; and (III) integrated magnetic inductors and transformers enable integrated power electronics such as (PwrSoC and PwrSiP) with >10x enhanced operation frequency and significantly reduced SWAP-C. Because switching at higher frequency enables the use of smaller inductors, the evolution of an integrated power supply is highly correlated to an increase in the switching frequency, i.e., 1–30MHz for co-packaged or stacked power supply in package (PwrSiP) and to the very high frequency (VHF) range of 30–300 MHz for PwrSoC. These low-loss thick ferrite films with a high relative permeability µr >3000 coated on Si and ultra-thin 100µm PCBs lead to novel magnetic PCBs with a high equivalent relative permeability of µr ~150 for a 106µm thick ferrite/PCB/ferrite sandwich structure. These high-permeability ferrite/PCB/ferrite sandwiches have been laminated to achieve thick (0.1~2mm) magnetic PCBs with relative permeabilities of µr >100, which is ~20x of the best commercially available magnetic PCBs and will enable power systems with significantly reduced SWAP-C with improved performance.