XPS analysis of the groove wearing marks on flank face of diamond tool in nanometric cutting of silicon wafer

Abstract

In nanometric cutting of single-crystal silicon wafers with a diamond tool, minimizing the tool wear is of great significance in order to achieve the satisfied surface quality and dimensional accuracy. For in-depth understanding of the tool wear mechanisms and the associated key factors, an X-ray photoelectron spectroscope (XPS) was employed to detect the chemical compositions of the wafer surface layer generated in the machining. The experimental results reveal that two hard particles, i.e. the silicon carbide (SiC) and diamond-like carbon particles, are generated during cutting, and then those particles scratch and plough on the tool flank face so as to form the groove marks, which lead to the heavy tool wear. The inspections further indicate the carbon diffusion is essential for the formation of SiC and diamond-like carbon particles, and the concentration of diffused carbon left on the machined surface declines along with the increase in cutting distance. Therefore, an efficient solution to suppress the tool wear is much needed, particularly for preventing the diffusion of diamond carbons into silicon wafer. Moreover, the formation of SiC and diamond-like carbon particles has no anisotropy although different crystalline planes of the diamond crystal are used as tool rake and flank faces through orientation arrangements. However, their resistances to the carbon diffusion present visible anisotropy.