SiC wafer bonding by modified suface activated bonding method

3-inch 4H-SiC wafer bonding has been achieved by the modified surface activated bonding (SAB) method without any chemical-clean treatment and high temperature annealing. Strong bonding of the SiC wafers, greater than 32MPa (tensile strength), was demonstrated at room temperature under 5kN force for 300 seconds. Almost the entire wafer has been bonded very well except the small outermost region and few voids. The interface structure was analyzed to explore the bonding mechanism. An amorphous layer was found to be as the intermediate layer at the interface. Furthermore, to verify the stability of the interface, the interface changes after annealing were studied.