Nanometric ductile cutting characteristics of silicon wafer using single crystal diamond tools

Abstract

In current wafer fabrication, most machining processes, such as slicing, edge grinding, finishing, lapping, polishing, back thinning, and dicing, are based on grinding or abrasive process, which always generated microcracks and subsurface damage. In this article, theoretical analysis on ductile mode cutting of silicon wafer showed that the machined silicon surface with free of fracture and nanometer scale surface roughness can be achieved when dislocation dominated the chip formation rather than crack propagation. Nanometric cutting on silicon wafers using an ultraprecision lathe with a single crystal diamond tool has been carried out to verify ductile cutting performance of silicon wafer. The machined workpiece surfaces and diamond tools used were examined using scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The experimental results are found to well substantiate the analytical findings, and nanometric ductile mode cutting of silicon wafer has been successfully achieved under the critical cutting conditions.