Bohr Materials

Single-Crystal Heat Sinks

Five square single-crystal diamond plates arranged on a white background.

Grain-boundary-free single-crystal diamond, the highest thermal conductivity available in a heat sink.

Removing the grain boundaries of the polycrystalline grade takes thermal conductivity above 1800 W·m⁻¹·K⁻¹ at 300 K, the highest available in any heat sink material.

The trade is area. Single-crystal pieces run to 24×19 mm, where the polycrystalline grade goes to 150 mm in diameter.

  • Ultra-high thermal conductivity
  • Low thermal expansion coefficient
  • Excellent electrical insulation
  • Chemical stability and mechanical strength
  • Polycrystalline gives the larger size capability; single-crystal gives the higher thermal conductivity

Specifications

Thermal conductivity at 300 K> 1800 W·m⁻¹·K⁻¹
Thermal diffusivity at 300 K> 1000 mm²·s⁻¹
Thermal expansion coefficient at 300 K1.0 ± 0.1 ppm·K⁻¹
Specific heat capacity at 300 K0.502 J·g⁻¹·K⁻¹
Hardness70 – 120 GPa
Young's modulus1050 GPa
Poisson's ratio0.1
Density3.52 g·cm⁻³
Resistivity1.0×10¹² – 1.0×10¹³ Ω·m
Surface roughness Ra< 5 nm
Reference sizes24×19, 15×15, 10×10, 9×9, 8×8, 7×7 mm (customisable)
Thickness0.1 – 5 mm (customisable)

Reference values from the producer datasheet. Dimensions marked customisable are set per order. Request a quote to have a specification confirmed against your drawing.

Applications

Single-crystal sinks are specified where the die is small, the flux is extreme and there is no room to spread heat laterally.

  • High-power semiconductor devices, including EV traction power modules
  • Optoelectronics: high-power LED lighting and solid-state lasers
  • Quantum technology: quantum chips and quantum sensors
  • Aerospace

See all Thermal Management or browse all products.