Corrosion, aluminum and copper

A failure mechanism in semiconductor devices. Corrosion failures can occur when ULSI devices are exposed to moisture and contaminants. Corrosion failures are usually classified as one of two broad groups: bonding pad corrosion or internal chip corrosion. Bonding pad corrosion is usually more common simply because the die passivation does not cover the metallization in the bonding pad locations. Internal chip corrosion (internal to the chip, away from the bonding pads) can also occur if some weakness or damage exists in the die passivation, which would permit the moisture and contaminants (e.g., chlorine ions) to reach the metallization. (Reference JEP122F)