Wire-bonding process suits high-temperature applications

IC Interconnect said its Ni/Au (nickel/gold) pad resurfacing process for automotive and other wire bond applications produces bonds that are stable at high temperatures despite having a thinner gold layer (0.1µ vs. 1 µ or more). The process eliminates the Kirkendall voiding that takes place in an Al/Au interface at 200 °C thermal exposures, the company said.

“Electroless Ni/Immersion Au is an inexpensive method to enable standard gold wire bonding to be extended to the thermal demands required of today’s state-of-the-art electronics,” said company president Curt Erickson. “Products made with our Ni/Au process have been tested and qualified by several customers.”

Erickson added that Nickel/gold pad resurfacing provides benefits for copper-based ICs. Compared with aluminum plating on copper pads to avoid corrosion, nickel/gold plating is maskless, and thus avoids the costs associated with thin film sputter, photo lithography and metal etch.