Effects of K3[Fe(CN)6] slurry's pH value and applied potential on tungsten removal rate for chemical-mechanical planarization application

In this work, in order to determine effects of corrosion and wear on tungsten removal rate, attempts were made to investigate corrosion, wear, and corrosive wear behavior of tungsten in K3[Fe(CN)6] slurries. Electrochemical and tribological experiments were carried out for different slurry pH values and potentials using a rotating pin-on-disc tribometer. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to characterize surface films formed at the different pH levels and potentials. It was demonstrated that the tungsten removal rate increased with increasing slurry pH and potential. Mechanisms involved are discussed.