Platinum wire wedge bonding: a new IC and microsensor interconnect

We describe a new means of making electrical connections between die and chip header. Interconnects are made by using a conventional wire bonder to ultrasonically wedge bond 0.032 mm diameter Pt wires to both Pt and Al thin films. Interconnects made in this manner are remarkably strong. Electrical measurements show contact resistances of less than or equal to 0.05 Omega . Annealing tests show that bonds made to thin metal films of Pt on Ti on sapphire show no appreciable signs of electrical or mechanical degradation after anneals at 900 degree C for 1 h in pure oxygen.