Double-sided <111>-oriented nanotwinned copper foils for thermal interface materials in high power electronics

Double-sided <111>-oriented nanotwinned copper foils with 99% highly <111> orientation and low roughness on both surfaces are fabricated for diffusion bonding. We succeed to use them to bond copper substrates and silicon substrates at 300 °C for 30 min with excellent bonding quality and bonding strength. With the high melting point, thermal conductivity, and bonding strength, the Cu foils show great potential for thermal interface materials in high power electronics.