SLICING MECHANISM OF MULTI-WIRE SAWING USING ELECTROPLATED DIAMOND WIRE

Multi-wire sawing, with fixed diamond abrasives, has been widely used for wafer mass production. However, the slicing mechanism has not been clarified completely, and the optimum slicing conditions are still determined through trial and error. In this study, the slicing mechanism of fixed abrasive wire sawing, using an electroplated diamond wire, was investigated experimentally. First, the diamond wire stiffness, and the relationship between normal cutting force and wire deflection, were discussed. Second, the influence of slicing conditions on cutting forces and the surface topography of the sliced wafer were investigated in detail. Third, a new analysis model based on a material removal method was proposed. The average abrasive cutting depth and the specific cutting energy were calculated at various slicing conditions namely, the wire speed, the feeding speed and the wire tension. Finally, the relationship of the average abrasives cutting depth to slicing characteristics and wafer quality were discussed. It was clarified that the average abrasive cutting depth is closely related to wafer quality and cutting characteristics. The material removal behavior changes with the average abrasives cutting depth. The size effect appears at a small cutting depth and brittle mode cutting becomes dominant at a large cutting depth.