An investigation on Cu wire bond corrosion and mitigation technique for automotive reliability

The increase of gold price had pushed industrial to develop copper wire in order to stay competitive. However, copper is not precious material like gold, there are numerous challenges in bonding & reliability risk associated with stringent automotive reliability requirements. Corrosion associated with copper wire bonding is considered one of the hard to solve reliability risk as the occurrence is in very low ppm and there was no specific pattern observed on the corroded bondpad location. This paper is focusing on the copper wire interconnect with Aluminum pad corrosion in humidity test including autoclave and temperature humidity bias test.