April 23, 2010 – A seminar held at last month’s SEMICON China reiterated points made earlier in the year by an industry group that there are still questions about using copper bonding wire vs. gold in semiconductor packaging applications.

Feedback from participants at the seminar on wire bonding and wire bond reliability, which sponsored by the London-based World Gold Council — an organization focused on creating demand for gold — echo results from a SEMI survey in January that seemed to suggest reservations about Cu wire reliability and yield. "About 50% of the attendees at the event have encountered problems with copper wire bonding in production, including low production yields," according to Richard Holliday, director of the Council’s industrial interests.

Acknowledging that the high price of gold necessitates some kind of change in its use for packaging, he instead suggested that wire suppliers and their customers still leverage "the inherent reliability" of the metal, while seeking to offset gold costs in ways — e.g., minimize wire usage through optimizing the loop height, smaller diameters, and making design changes. The WGC’s message is that despite a fledgling industry migration to replacing gold wire bonds with copper, Cu is "a cost-effective choice in many applications," with "material properties [that] are best suited to the wire bonding process."