Abstract
In CMP, the polishing variables affect the removal rate as shown in Preston′s equation. Furthermore, the characteristics of consumables (slurry, pad and conditioner) also affect the removal rate. Additionally, there is a need for high removal rate in sapphire-CMP. The objective of this study is to investigate the effect of the polishing variables on the removal rate in sapphire-CMP. This paper discusses following three experiments; (I) relationship between the mechanical polishing variables (polishing pressure, rotation speed of platen/ wafer) and the removal rate, (II) relationship between the slurry concentration and the removal rate, and (III) the effect of slurry dropping point on the removal rate. In experiment (III), we also observe the quantitative evaluation results of the slurry flow. As a result, the following points were observed. (1) The removal rate increase with increase in the polishing pressure and the rotational speed of platen/ wafer. (2) The removal rate reaches saturation with the increase of the slurry concentration. (3) The slurry dropping point affects the slurry flow between the wafer and the pad and the removal rate.
