Guidelines for improving intermetallic reliability

As wire bonding continues to advance, new challenges are resolved. In ultra-fine pitch bonding (<50/spl mu/m pitch), efforts to maximize wire diameter have resulted in specialized contained inner chamfer (CIC) capillaries, that reduce friction between the wire and feed hole, allowing the use of larger diameter wire without feed and interference problems. New wires have been developed that provide significantly improved intermetallic reliability after thermal aging of small diameter ball bonds. Bonders with improved z-axis control provide greater control of impact forces for improved intermetallic formation and coverage.