Abstract: based on the examination and analysis of the morphology and mean size of abrasives as well as abrasive size distribution by scanning electron microscope (SEM) and high resolution particle analyzer, the influence of the abrasives and chemical compositions on the material removal rate and surface roughness during chemo-mechanical polishing of MgO single crystal substrate was studied. The results showed that high material removal rate and better surface roughness could be achieved with the slurry containing phosphorous acid and SiO2 abrasive particle in spherical shape and in a narrow size distribution. Optimized parameters, including down force 42 kPa, carrier speed 100 r/min, slurry flow rate 30mL/min, were selected during the chemo-mechanical polishing of MgO single crystal substrate. The material removal rate could reach 400nm/min and the surface roughness Ra as low as 0.4nm. the polishing parameters and the slurry developed and presented in this paper could be used as a reference for the practical production.

Keyword: single crystal MgO substrate chemo-mechanical polishing material removal rate