Core-Shell Engineered Fillers Overcome the Electrical-Thermal Conductance Trade-Off

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Modern electronics require thermal management materials with tunable electrical properties (conductive, dielectric, insulating).
• A key challenge is the trade-off between high thermal conductivity and high electrical conductivity in existing materials.
• Electrically insulating, yet highly thermally conductive materials are scarce, limiting diverse electronic applications.

Purpose of the Study:

• To overcome the electrical-thermal conductance trade-off in thermal management materials.
• To develop a versatile and robust method for preparing engineered core-shell fillers.
• To create advanced composite materials for thermal management in electronic packaging.

Main Methods:

• A facile Pechini-based method was employed to synthesize multiple core (metal)/shell (metal oxide) engineered fillers.
• Examples include aluminum-oxide-coated and beryllium-oxide-coated silver (Ag) microspheres.
• The method was combined with ultrafast joule heating treatment for versatility with varied filler sizes, including large ones.

Main Results:

• The synthesized core-shell fillers, when compounded into epoxy composites, exhibited high isotropic thermal conductivity (approximately 3.8 W m⁻¹ K⁻¹).
• These composites maintained high electrical resistivity (approximately 10¹² Ω cm) and good flowability.
• The resulting composites demonstrated superior heat dissipation compared to commercial thermally conductive packaging materials.

Conclusions:

• The developed core-shell fillers enable the creation of thermally conductive composites with controlled electrical properties.
• This approach offers a robust solution for emerging electronic packaging applications requiring efficient thermal management.
• Demonstrated applications include circuit board and battery thermal management, highlighting practical utility.