The Influence of the Heat after Bonding on the Separability at Gold Wire Bonding Area

Abstract

The influence of the heat after wire bonding on the separability between Au wire and Ag plating on Cu alloy substrate has been investigated, and the position that introduces the separation technique of bonding wire into the packaging process of CSP is examined. Bonding strength decreases with decrease in the bonding temperature and bonding strength and contact area have a linear relation. Furthermore, when heat treatment is performed after wire bonding, the strength tends to saturate after increasing, and the separability in the bonding area bars from an early stage. Based on the above results, wire bonding should be done at temperature as low as possible in the packaging process of CSP, a substrate should be peeled off making wires separable just before the post cure. © 2003, The Japan Institute of Electronics Packaging. All rights reserved.