Relationships among Carrier, Friction Coefficient and Removal Rate of Double-Sided Polishing: Effect of Carrier on Friction Coefficient between Polishing Pad and Substrate and Correlation of Friction Coefficient and Removal Rate

Double-sided polishing (DSP) method is widely used in manufacturing process of sapphire substrate for LEDs. Since, several studies on the DSP method have been actively reported, however, it is not enough from the practical viewpoint such as the effect of carrier, polishing pad surface asperities and kinematic friction characteristics on the removal rate. This study focuses on the carrier used in the DSP as well as aims to elucidate the carrier characteristics and the kinematic friction coefficient for obtaining the high removal rate. In this paper, the effects of slurry hole area ratio and surface properties of carrier on the removal rate in upper/ lower surfaces of substrate were examined. Moreover, in the kinematic friction characteristics between the polishing pad and the substrate, the friction characteristics in the DSP were observed. As a result, the removal rate and kinematic friction coefficient of the upper/ lower surfaces of substrate change depending on the slurry hole area ratio and surface properties of carrier, and there is a strong relationship between them.