AICu metal line corrosion: a case study

摘要

The evolution of aluminum corrosion (type A) with water content has been reviewed and detailed. The well known behavior of Al etch has been enriched with SEM images of the etch sequence. Chloride is identified as responsible for corrosion type B. A galvanic corrosion through chloride in air is giving a "worm-like" defect. We have shown that the same effect is found in a wet environment, giving a "cave-like" defect. The presence of chloride has been measured by EELS and its role has been proven through AIT inspections. The chloride inside the polymer is way more significant than the one trapped in the Al_2O_3 sidewall passivation.