DIASEMI Insulated Diamond–Copper Composite
May13, 2026
DIASEMI Insulated Diamond–Copper Composite
DIASEMI develops an advanced insulated diamond–copper (Cu/diamond) composite by applying a dense Al₂O₃ coating via aerosol deposition. This approach transforms a highly thermally conductive but electrically conductive material into an electrically insulating heat spreader suitable for high-voltage applications.
The conformal Al₂O₃ layer (~9 μm) preferentially deposits on the Cu matrix and extends across diamond surfaces, enabling full surface insulation with electrical resistivity ~10¹² Ω·cm. The composite achieves a dramatic increase in electrical resistance (from ~10⁻⁶ to 10⁹ Ω) while maintaining ultra-high thermal conductivity (~800 W/m·K), with minimal degradation.
Compared to diamond–SiC composites, the DIASEMI insulated Cu/diamond platform delivers significantly higher thermal conductivity (≈800 vs 200–500 W/m·K) and superior heat spreading, while maintaining comparable thermal expansion and electrical insulation.
This technology enables a new class of high-performance substrates for power electronics, RF systems, and laser applications, combining the thermal advantages of metals with the electrical functionality of ceramics.
Key Comparison
Thermal conductivity: Cu/Diamond (~800) >> Diamond/SiC (200–500 W/m·K)
Electrical property: Both insulating (DIASEMI via coating)
Thermal spreading: Cu/Diamond superior
Application: Cu/Diamond better for ultra-high heat flux devices