Ion beam modification of ceramic component prior to formation of AlN-Cu joints by direct bonding process

Ion implantation was utilized as a pre-treatment method for direct bonding of ceramics with copper. Aluminum nitride samples were implanted with metallic ions (Ti, Cr, Fe, Cu) and/or with oxygen. The choice of implanted species was based upon thermodynamic considerations. Direct bonding was performed by a conventional method of furnace annealing in nitrogen atmosphere. Shear strength measurements of the joints were used as a method of joint quality verification. The samples were additionally characterized by RBS measurements and the shear fracture surface was analyzed by optical microscopy. It has been concluded that the joints formed on ion implantation pre-treated aluminum nitride exhibit superior quality with respect to conventionally treated (oxidized) material. It has also been found that the optimum properties are exhibited by material in which thin titanium nitride surface layer is formed by low-fluence Ti implantation and that the presence of oxygen has a detrimental effect upon the joint quality, although oxygen implantation is potentially a promising approach. (c) 2007 Elsevier B.V. All rights reserved.