A New Copper Wire Ball Bonding Process Methodology

Copper wire bonding as a replacement to the long established gold wire process has gained significant momentum in the last years. Wire bonding specialists have struggled with copper's mechanical, physical and chemical differences to gold, in developing robust processes that are able to maintain similar yield, output and quality levels of gold wire bonded products. This article shows the results obtained in a new wire bonding process concept, in terms of key requirements that are used to guard Cu wire bonded products against the two most common failures in such products: inter-Metallic Compound (I MC) corrosion and bond pad cratering damage. The new process concept is compared, in terms of the same metrics, to the more traditionally used Double Load [1,2] process principle commonly used for Cu wire processes.