Susceptibility of Microweids in Hybrid Microcincuits to Corrosion Degradation

Analysis of broken ultrasonic Al-Ag bonds involving SEM electron microprobe, ion microprobe, and Auger electron spectroscopy indicated that failure was due to corrosion. Subsequent environmental tests demonstrated that Al-Ag bonds are highly susceptible to corrosion, but Al-Au and Au-Al bonds are less so. No evidence of corrosion of Au-Ag bonds was found.