The Wire Sawing Process of Silicon Wafers Studied by Hardness Indentations

Wire sawing of silicon wafers using a cutting fluid consisting of PEG and SiC has developed into a mature technology in the PV industry. Further progress in improving cutting speed and wafer quality may require a detailed understanding of the material removal process. This work employs Vickers indentations to simulate the SiC – Si interaction in wire sawing. The size, shape and frequency of chipping are found to be highly dependent on the indenter’s orientation relative to the [100] direction on a (001) surface. The authors propose that this anisotropy is founded partly in cracking behavior during loading, and partly in the formation, and relaxation, of dislocations generated in phase transformed structures of pressure induced silicon.