Here is the abstract you requested from the Wirebond_2009 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Copper Wirebonding without the Plasma|
|Keywords: wirebonding, copper, cleaning|
|Wirebonding to copper has always been problematic due to the formation of oxides. Unlike aluminum pads which can be plasma cleaned and remain wirebondable for significant times, the oxide that quickly forms on copper is difficult to wirebond. Unlike aluminum and gold pads where adding heat makes the more difficult pads manageable, adding heat to the copper pads only compounds the problem. A process is under initial stages of development that show promise for wirebonding copper pads. Pad that were not bondable at time zero were effectively cleaned and made wirebondable without using a plasma etch or compromising the integrity of the copper layer. Even 23 hours latter over 95 percent of the pads maintain a +13 gram shear force. All at room temperature!|
|Terence Collier, Owner