Ion implantation as a pre-treatment method of AlN substrate for direct bonding with copper

Ion implantation was examined as a pre-treatment procedure for AlN substrates used for direct bonding with Cu. It replaces the conventional process of thermal oxidation. Ti, Fe and O ions were used at acceleration voltages of 15 and 70 kV in the dose range between 1016 and 1018 ions/cm2. Shear strength measurements of the prepared joints have shown that the optimum results are obtained for Ti implanted at 15 kV to a dose of 5×1016 ions/cm2. The bond strength attained for such conditions exceeds that of conventionally prepared joints by a factor of 5. The morphology of fractured joints was studied by SEM and discussed in terms of changes induced by the implanted ions.