A series of nano scale scratching experiments on the surface of single crystalline silicon wafer was designed to simulate the process of Chemical Mechanical Polishing(CMP), and the damage of surface and subsurface of single crystalline silicon wafer after was studied by the modern analysis instruments and technology. The results indicate that, under certain working condition with the proper parameters when the mechanical effects matching the chemical effects, the optimized material removal rate can be obtained with the best polished surface quality, that is, the minimized damage of surface and subsurface. The material removal rate is raised with the enhancement of mechanical effects, but the damage of the surface and subsurface is increased after the mechanical effects reach a certain level; the chemical effects improve the material removal rate by the mechanical effects, but the polishing surface may be damaged by the chemical effects. By adjusting mechanical parameters of pressure and speed the heat from the tribological chemical reaction can be controlled, so as to realize the control of the tribological diffusing chemical reactions by the mechancial effects, decrease the use of chemicals in the superprecision polishing of the single crystalline silicon wafer and realize the green polishing.