Study on the subsurface microcrack damage depth in electroplated diamond wire saw slicing SiC crystal

Abstract

At present, the fixed-abrasive wire saw machining technology is widely used in the slicing process of SiC single crystal. And the subsurface microcrack damage depth of wire sawn SiC wafer is an important quality control parameter. In this paper, experimental and numerical analysis of the subsurface microcrack damage depth of single-crystal SiC in wire sawing is presented. A finite element model (FEM) which was used for simulation and calculation of subsurface microcrack damage depth in wire saw slicing SiC crystal wafer was established. The variations of maximum principal stress and stress change rate of sawn crystal and slice in wire sawing were analyzed, and the validity of the FEM was verified by sawing experiment. Further, microcrack damage depths under different ingot feed speeds and wire speeds were predicted and the influence of process parameters on microcrack damage depth was discussed. Research results show that the microcrack damage depth values of simulation are lower than the experimental measurement, but with a consistent change trend of a relative error is less than 15.92%. The subsurface microcrack damage depths of sawn wafer decrease with the increase of wire speed and decrease of feed speed. The research results can be helpful to develop precision and high quality slicing technology of SiC single crystal.