Investigation on inhibition of ruthenium corrosion by glycine in alkaline sodium hypochlorite based solution

Removal of Ru by etching in alkaline sodium hypochlorite (NaClO) based solution is carried out. The glycine on the corrosion of Ru in NaClO based solution is systematically investigated. The results show that in the alkaline NaClO solution, glycine is a good corrosion inhibitor for Ru. Through electrochemical measurements, electrochemical quartz crystal microbalance (EQCM) and X-Ray photoelectron microscopy (XPS) measurements, it is found that the glycine adsorption isotherm on the Ru surface follows TEMKIN's model. Glycine can not only adsorb on the Ru surface to inhibit the corrosion of Ru, but also promote the dissolution of the formed oxide layer through complexing action. Finally, we use glycine and NaClO for chemical mechanical polishing (CMP) of the Cu/Ru interconnect structure and the removal rate selectivity of Cu and Ru can be adjusted to 1:1.