Nanoscale friction and wear properties of silicon wafer under different lubrication conditions

The nanoscale friction and wear properties of single crystal silicon wafer under different lubrication conditions are studied in this paper. The experiments were performed with Si3N4 ball sliding on the surface of silicon wafer under four different lubrication conditions: dry friction, water lubrication, hydrogen peroxide lubrication and the static hydrogen peroxide dry friction. The results from the experiments have been analyzed showing the different friction and wear properties of the silicon wafer in different lubrication conditions. It is concluded that the wear rates under the water lubrication and under the hydrogen peroxide lubrication are both small, the chemical reactions are facilitated by the mechanical processes when the load and the sliding speed reach certain levels. This is mainly resulted by the enhanced lubricant performance with the formed silicon hydroxide Si(OH)4 film. Under the water lubrication, the wear is found in a way of material removed in molecule scale. Under the hydrogen peroxide lubrication, the wear is mainly caused by the spalling of micro-cracks. Under the dry friction condition, the wear is found being adhesive wear. And under the static peroxide dry friction, the wear is prevailing adhesive wear. These results are essential and valuable to the development of the efficient and environmental-friendly slurry for the chemical mechanical polishing (CMP) process.