Chemical mechanical polishing performances by filtering and retreatment of used silica abrasives slurry

In order to reduce the high cost of ownership and cost of consumables, we have collected the silica abrasive powders by filtering method after subsequent chemical mechanical polishing (CMP) process for the recycling of abrasives. From this, we have studied the possibility of recycling reused silica abrasive through the analysis of particle size distribution and field emission scanning electron microscope measurements of abrasive powders. We annealed the collected abrasive powders to promote the mechanical strength of reduced abrasion force. Finally, we compared the CMP characteristics between self-developed KOH-based silica abrasive slurry and original slurry. Our experimental results show removal rate and planarity comparable to commercial products. Consequently, we can expect the saving of high cost slurry.