Ultra thin Extra Large-Sized, Super High Thermal Conductivity Diamond/Copper Composites

Ultra thin Extra Large-Sized, Super High Thermal Conductivity Diamond/Copper Composites

A high-thermal-conductivity diamond/copper (diamond/Cu) composite was fabricated by Diasemi using an improved gas-pressure infiltration process. The method introduces interfacial modification and stepwise cooling to enhance bonding and reduce interfacial thermal resistance.

Diamond particles (90–400 μm) were coated with Ti or W films (50–400 nm) by magnetron sputtering, packed into graphite molds at 60–85% volume fraction, and preheated at 1000–1050°C for 1–5 h under argon to form uniform carbide layers (TiC, WC). Molten Cu or Cu-alloy (Cu–Ti, Cu–Cr, Cu–Zr, Cu–B) was then infiltrated at 1100–1300°C under 0.5–10 MPa for 5 min–3 h, followed by controlled cooling (4°C/min above 300°C, 2°C/min below 300°C).

The resulting composites exhibit uniform interfaces, dense microstructure, and thermal conductivity up to 1500 W/m·K. The process enables thin, large-area plates (0.2–4 mm thick, up to 150 mm wide) suitable for high-power electronics, lasers, and microwave device heat spreaders.