Miniaturized 3D Glass Package for High-Efficiency and High-Power Density 48V DC-DC Converters

A 3D glass packaging solution has been developed as a power brick module for high-efficiency, high-power density 48 V DC-DC converters, which are essential for applications such as data centers, telecommunications, and autonomous driving. As compute power demands increase, transitioning from 12 V to 48 V architectures significantly reduces power distribution losses. By leveraging 3D heterogeneous integration, the presented design features vertical stacking of passive and active components, including an isolated supply, a digital signal isolator and a GaN half-bridge, within a modular power brick. The top placement allows for various cooling options for the thermal management, as the half-bridge is designed for high currents up to 35 A. The package employs three precisely structured glass substrates, utilizing selective laser-induced etching and laser ablation to form complex glass geometries and conductive paths. The electrical functionality of the circuit is validated in an 48 V application with an isolated ground. With the 3D integration in a glass-based package, a footprint reduction of 56% compared to a traditional planar PCB implementation is achieved. These advancements underscore the potential of glass substrates for enhancing power density and facilitating the integration of glass packages in future 48 V applications.