Research on the fretting wear behavior of silicon wafers before and after carbon ions implantation

Carbon ions with different doses of 2×1015 and 2×1016 ions/cm2 were implanted into single crystal silicon wafers under an energy level of 80 keV. The nanohardness and elastic modulus of silicon wafers were studied on the nano-mechanical testing system. The fretting wear tests were performed on the UMT-2 Micro-tribometer to evaluate the fretting wear resistance of C+ implanted silicon wafer and to investigate its micro-tribological properties. The results demonstrate that the nanohardness and elastic modulus of silicon wafer with dose of 2×1015 ions/cm2 decreased and those of 2×1016 ions/cm2 changed little. Implanted silicon wafer with dose of 2×1016 ions/cm2 had much lower coefficient of friction and wear volume under low loads, which suggests a significant effect of friction-reducing and anti-wear. The results also indicate that abrasive wear was the main wear mechanism for both virgin silicon and C+ implanted silicon with dose of 2×1015 ions/cm2. However, adhesive wear played a significant role in the wear mechanism of the C+ implanted silicon with dose of 2×1016 ions/cm2 under the low loads, while the abrasive wear dominated the wear mechanism under high loads.