PDF 0.28 MB CMP Slurry Measurement Using Laser Diffraction Chemical mechanical polishing is the most popular technique for removing the surface irregularities of silicon wafers. Typical CMP slurries consist of a nano-sized abrasive dispersed in acidic or basic solution. A chemical reaction softens the material during mechanical abrasion. The abrasive particles have a size distribution which directly affects critical metrics including rate of removal and wafer defects. Particle size analysis is therefore a key indicator of CMP slurry performance. The popularity and utility of several particle sizing techniques will be discussed within.