Three-Dimensional Integrated GaN-based DC-DC Converter with an Inductor Substrate

Generally, the improvement of power density is achieved by increasing switching frequency and using three dimensional (3D) integration technology. The emergence of gallium nitride (GaN) devices can increase switching frequency dramatically and facilitate the realization of 3D integration. By using the 3D integration technology, the structure of power converter can be reconfigured to realize a high space filling rate, and thus to improve the power density. However, the space reconfiguration also changes the magnetic flux distribution and has an impact on the thermal performance of power converter. This paper takes one of the 3D integrated structures as the example for demonstration, which uses a planar inductor as the substrate for the rest parts of power converter. By using finite element analysis (FEA) tool, in-depth study on parasitic inductance and thermal performance of 3D integrated GaN-based power converter was conducted, and experimental prototype was built for verification.