Corrosion inhibition of Cobalt during post-Chemical Mechanical Planarization Cleaning

Inhalt:
Cobalt has been utilized as contact plugs and interconnections, but corrosion easily happens during polishing and cleaning process. This work investigates corrosion inhibition in alkali solution using electrochemical analysis such as static etching corrosion experiments and potentiodynamic polarization measurements. It is found that some surfactants adsorb on the cobalt surface, prevent the oxidation of cobalt and could inhibit the corrosion of cobalt. We also elucidated that strength as a corrosion inhibitor depends on alkyl chain length of surfactants. Keywords: post-Chemical Mechanical Planarization Cleaning, Cobalt, Corrosion