Effect of Abrasive Particle Size Distribution on Removal Rate of Silicon Wafers

The effects of silica abrasives of five different particle sizes (10 nm, 40 nm, 60 nm, 80 nm and 100 nm) on the removal rate of silicon wafers were studied. The experiments were performed under two conditions, by taking the abrasive particles of uniform size and of two different sizes. The mixture of abrasive particles of two sizes increased the removal rate of the silicon wafer, and this improvement was more apparent when 10 nm particles were mixed with any other particle size. According to the stability of the slurry, the size pair of 10 nm and 60 nm presented the optimal result for the particle size mixing of abrasives. The physical model of the abrasive distribution between the silicon wafer and the polishing pad was established. The mechanism of the effect of mixed abrasive on the increase of silicon wafer removal rate was presented. Further, the contact area between the abrasive and silicon wafer was calculated by MATLAB. Based on this, the removal rate of the silicon wafer by the abrasive with mixed-sized particles was predicted with an error value of less than 10%.