Interface Structure and Bonding Properties of Cu/AlN Material Fabricated by Direct Bonded Copper Process

By direct bonded copper (DBC) process, Cu/AlN material was fabricated successfully on AlN ceramic substrate at bonding temperatures of 1 000-1 060℃. The bonding strength, morphology and phase composition of Cu/AlN interface were investigated by mechanic testing equipment, field emission scanning electron microscope and X-ray diffractometer. The results show that the bonding strength of Cu/AlN interface was more than 8.0 N·mm^-1, a transition layer with thickness of 2 μm was found between copper foil and AlN ceramic, the transition layer was mainly composed of Al₂O₃, CuAlO₂ and Cu₂O. The bonding strength of Cu/AlN interface increased as the bonding temperature gradually went up.