3D Power Packaging for Green Energy

Power semiconductors are vital components of all electronic systems, from smartphones to automobiles, and improvements in power semiconductors accelerate the transition toward a green economy.

Newer, more sophisticated DC/DC converter designs are helping reduce energy consumption through increased power conversion efficiency. The best DC/DC converters have conversion efficiencies greater than 95%, leveraging design innovations and access to new materials such as silicon carbide (SiC) and gallium nitride (GaN). Green technology product designers have noted that the number of power semiconductors used in the global renewable energy market is expected to grow at a compound annual growth rate (CAGR) of 8–10% between now and 2027.

Efficiency is one piece of the puzzle; improved power density is another because it allows designers to fit more power into the same volume. A new application can provide more functionality in the same space as its predecessor or equivalent functionality in a smaller space. This is particularly important as many green applications replace mechanical devices with electronic counterparts. For example, electric vehicles (EVs) replace belt-driven mechanical HVAC units and power steering pumps with electronic versions that must still fit into the limited space under the hood. Additionally, reduced size leads to lower weight, which increases vehicle range.

Maximizing system performance includes optimizing the power subsystem, which consists of power supplies, power conversion devices, filters, protection devices, and interconnects such as connectors, wires, cables, and circuit board traces.

Key metrics include size, weight, and power (SWaP) or SWaP-C when cost is included. Three-dimensional power packaging (3DPP) is an advanced packaging technique that enables high-density integration while optimizing SWaP-C. 3DPP employs advanced assembly processes to achieve maximum power density with a minimal footprint. When applied to surface-mount DC/DC converters, 3DPP allows for best-in-class performance while maintaining small footprints. This results in power products that are smaller than conventional power conversion modules while remaining highly efficient without increasing footprint cost.

3DPP eliminates the need for an internal printed circuit board (PCB) by directly mounting components onto a lead frame, significantly reducing module space requirements. This enables streamlined PCB profiles with integrated power conversion—eliminating the need for a custom converter design.

Numerous manufacturing advancements contributed to 3DPP technology, including:

• Embedded passive and active components
• Flip-chip technology
• Reduction of inductive and capacitive parasitics from internal package interconnects
• Planar magnetics, such as inductors and transformers, for compact, controlled, and repeatable power designs