Room-temperature direct bonding of diamond and Al

Direct bonding of diamond and Al is achieved by surface activated bonding at room temperature. The interfacial structures of the diamond/Al bonding interface with annealing at different temperatures are investigated under in-situ annealing in a transmission electron microscope (TEM). An amorphous layer with a thickness of 4 ± 0.5 nm is formed at the bonding interface without annealing, the thickness of the amorphous layer decreases with increasing annealing temperature, the amorphous layer vanished after annealing at 600 °C. No structural defects are observed at the bonding interface with annealing at different temperatures.