Inhibition effect of glycine on molybdenum corrosion during CMP in alkaline H2O2 based abrasive free slurry

The inhibitory effect of glycine on corrosion and chemical mechanical polishing (CMP) of Mo in hydrogen peroxide (H2O2) based abrasive-free alkaline slurry has been investigated. Results show that, in H2O2 based slurry, both static etching rate (SER) and removal rate (RR) of Mo during chemical mechanical polishing were reduced by adding glycine and the inhibition efficiency was around 50%. From ex-situ and in-situ open circuit potential (OCP), current density transient and potentiodynamic polarization measurements, it is found that formation of oxides was delayed due to blocked contact between oxidizer and the sample surface by electrostatic adsorption of glycine zwitterion on the surface. Glycine can form complex with MoO3 and promote dissolution of surface oxide, MoO3, resulting in a reduced passivation layer. The slowed oxidation reaction dominates the whole process, resulting inhibited Mo corrosion and leading to a smoother Mo surface. (C) 2017 Published by Elsevier B.V.