Power semiconductors using SiC wafers are superior to Si semiconductors with regard to low loss of electrical power, miniaturization and high efficiency of the power converter, realization of simplified cooling systems, etc. Therefore, SiC power semiconductors are expected to be applied in many fields. However, SiC is a hard and brittle material compared to cubic boron nitride or diamond. The process for slicing of SiC involves use of a multi-wire saw. This study examined the process of SiC slicing with a rocking vibration type wire saw using diamond slurry and resin-coated wire. This method sliced wafers by ductile mode and the damage layer on the surface of the SiC wafer was reduced to 58 nm.

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Precision slicing tests were performed for single-crystal silicon using a newly developed dicing wire saw system and diamond wires. The developed dicing wire saw enabled the slicing of thick workpieces composed of hard and brittle materials, which could not be sliced by conventional dicing machines. To achieve high precision and efficiency, the dicing wire saw system used tension control and high speed control technologies, which provide a maximum wire feeding speed of 2000 m/min. In this study, the diamond wire was driven in a single direction at a speed of 750 - 1750 m/min and the slicing force, wire wear, and workpiece surface roughness after slicing were investigated experimentally. The results showed that as a new slicing system, the developed dicing wire saw was useable for high-precision slicing of thick workpieces.

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