Formation of CuAlO_2 at the Cu/Al_2O_3 Interface and its Influence on Interface Strength and Thermal Conductivity

摘要

The criteria for the formation of a CuAlO_2 reaction phase at the Cu/Al_2O_3 interface are explored. Oxygen solutes up to 2 wt% were introduced into the copper first. The bonding was carried out at 1075℃. The reaction phase was observed only when the oxygen solute in copper before bonding was higher than 1.3 wt%. The CuAlO_2 phase is polycrystalline and covers only part of the interface. The CuAlO_2 grains interact with the crack, which improves the interface strength. As CuAlO_2 is not continuous at the interface, the thermal conductivity of the Al_2O_3/Cu/Al_2O_3 laminate is affected little.