Effect of chemical activity of bulk and pad materials on the redeposition layer during polishing of glass

Abstract A near-surface redeposition layer is formed in the chemical mechanical polishing process of silicate glasses. In this work, secondary ion mass spectroscopy analyzer and transmission electron microscope are used to investigate the effect of bulk and pad materials on the microstructure and contaminations of the redeposition layer. The results suggest that the polishing materials with higher chemical reactivity will generate a deeper redeposition layer with higher concentration of contaminant elements, which will improve the surface quality by mitigating the mechanical abrasion effect. Then, a more detailed chemical mechanism of the redeposition layer formation has been concluded according to the chemical reaction and arrhenius equation, which can explain the effect of bulk materials and polishing pad on the redeposition layer well. These findings are helpful to understand the chemical process of polishing and improve the lifetime and quality of optical components especially in UV or high-power laser systems.