Abstract
Single crystal Silicon Carbide (SiC) is drawing more and more attention as a new semiconductor because of its great properties in terms of heat and voltage resistance. In the manufacturing process of SiC wafers, wire electrical discharge machining (EDM) method is considered better than mechanical saw methods because of its high efficiency and high machined surface quality. But furthermore improvement of Wire EDM method is difficult because of the contradiction between the machining speed and wire diameter. Thus a new slicing method is required. In this study, the basic EDM characteristics of SiC was investigated and compared with that of steel. Then EDM slicing of single crystal SiC ingot by utilizing a foil disc electrode was proposed and the machining performance of this method was experimentally investigated. The effect of machining condition like discharge current, duration and polarity etc. on the machining stability, machining speed, and tool wear ratio were discussed. Experimental results made it clear that there is a big difference between EDM of SiC and steel. The new foil disc EDM method for slicing SiC ingot is feasible and it has potential for application as a new slicing method in the future.
