Experimental study on micro grinding of silicon wafer using polycrystalline diamond tool
摘要
Silicon is widely used as a substrate material in semiconductors, electronic IC chips, memory devices, sensors, etc. In addition, the demand for micro patterning method on silicon is increasing. However, silicon is a difficult-to-machine material to machine due to its high hardness and brittleness. Various patterning methods for silicon wafer such as lithography, etching, laser machining and micro grinding have been studied. Among these, micro grinding is efficient machining process for fabrication of micro patterns. In this study, D-shaped polycrystalline diamond (PCD) tool was fabricated by wire electrical discharge grinding (WEDG) and the machining characteristics of silicon wafer were analyzed. As feed per revolution decreased, critical depth of cut increased. Also, areal surface roughness (Sa) and grinding force (Fz) were decreased. As tool rotational speed increased, surface roughness and grinding force were decreased. Under the analyzed machining conditions of roughing and finishing, ductile mode machining was conducted on silicon wafer with crack-free surface. Also, micro feature was machined on silicon wafer.