An Experimental Study of the Polishing Process for MgO Single Crystal Substrate

In order to obtain ultra-smooth and damage free substrate surfaces for MgO single-crystal substrate with high polishing efficiency, an experimental investigation based on systemically designed polishing experiments are presented and discussed. Considering the structural characteristics and chemical properties of the MgO single crystal, the experiments use a polishing slurry containing SiO2 abrasives so that the process is performed under a combination of mechanical and chemical actions. The effects of the polishing process parameters, such as polishing pressure, rotational speed of polishing plate, and the flow rate and concentration of the polishing slurry, on the surface roughness and material removal rate (MRR) are analyzed. Finally, a recommendation is made for selecting the appropriate polishing parameters for MgO single crystal substrate, based on which a surface roughness of 0.3nm can be achieved on the MgO substrate in 20min of polishing time.