Assessing the wear degradation of tungsten in acidic solutions using a lubricated tribocorrosion model

The tribocorrosion property of tungsten plays a great role in the chemical mechanical polishing of tungsten plugs used in integrated circuits. This study applied a lubricated tribocorrosion model to tungsten, verified and calibrated the model using results from laboratory tribocorrosion experiments, and predicted the effect of the key parameters on the mechanical and chemical wear behavior of tungsten. The results showed that the model could be successfully applied to the tribocorrosion of tungsten considering that the prevailing wear mechanism and the electrochemical corrosion property of tungsten fulfills the model's basic concepts. The model was able to predict the influence of the material, mechanical, electrochemical and rheological parameters on the mechanical wear and chemical wear behavior of tungsten. The model could clearly distinguish the contribution of the mechanical wear and chemical wear to the total wear degradation of tungsten, which provides useful instructions on how to control the related parameters in order to obtain tailored removal rate and surface quality in tungsten's chemical mechanical polishing process.