The effect of contact types on SiC polishing process

Abstract

To better understand the effects of different contact types on polishing characteristics of SiC wafer, the different contact types during polishing are simplified as the self-rotation of diamond abrasives. Through molecular dynamics simulation, three different material removal modes are proposed and graphite structure after the wear of diamond was displayed. It is found that the material removal mode of 3C–SiC changes from cutting removal to adhesion removal via compression removal, and finally returns to cutting removal, with the increase of the abrasive linear velocity. The wear of diamond abrasive is the most serious when there is no self-rotation, and graphite will form after diamond is worn. When the abrasive only rolls forward, the wear of diamond abrasive is the least, and the material removal rate is also the least. The self-rotation of diamond abrasives can significantly reduce the structural damage of the workpiece and the increment of system temperature and potential energy. Also, the self-rotation of abrasives can reduce the tangential force, which leads to the decrease of friction coefficient. Based on the above results, it is proved that the self-rotation of abrasive particles in the polishing process cannot be ignored.