A comparative study on the material removal mechanisms of 6H-SiC polished by semi-fixed and fixed diamond abrasive tools

Comparative experiments involving processing SiC substrates with the semi-fixed and the fixed diamond abrasive polishing tool have been conducted in this study. The material removal mechanisms of SiC substrates are investigated by the surface topography of substrate, the wear appearance of abrasives in tools and the analysis of wear debris. The results indicate that the removal scale of diamond grits in the fixed abrasive polishing film is much larger because of the higher abrasive protrusion heights. Moreover, the unequal protrusion height of diamond abrasives can also easily create deep scratches and damages on the substrate surface. However, the removal scale of diamond grits in the semi-fixed abrasive polishing film is smaller due to the effect of abrasive yielding. The obtained smooth and scratch-free surface with nanoscale roughness can shorten the total processing time and cut the cost.