Betapure™ CMP Capsules DatasheetSource: 3M Purification Inc.
Betapure™ CMP filter capsules are high capacity depth filters optimized for oxide and metal slurries used in chemical mechanical planarization (CMP) applications. Betapure CMP filters are composed of all-poly propylene components and features a multi-zone "graded-porosity" design for the optimum level of particle classification. This novel construction provides enhanced flow characteristics, including low pressure drop, to minimize shearing of the slurry while providing superior service life.
The objective of a slurry filter is for the majority of particles to pass through it unchanged, while only removing the undesired or "oversized" particles. The over sized particle population is commonly referred to as large particle counts (LPC) and they typically form over time when the suspended particles in the slurry settle forming aggregates, agglomerates, and gels. Large particles can also be the result of adverse shipping conditions, shearing, slurry drying, and interaction with other distribution loop components such as fittings, tanks, piping, valves, and pumps. These large particles can scratch metal and interlevel dielectrics potentially causing wafer defects.