Suppliers to OEMs (original equipment manufacturers) and photochemical manufacturers are constantly innovating to ensure their solutions address new defect challenges. In the 1980s, when the minimum feature size was approaching 1.0 μm, 0.2 μm filters were used to eliminate the largest particles in photochemical manufacturing. As the industry pursues the sub-7 nm node, conventional filtration technology is challenged to meet industry needs. Membrane pore size reduction alone is no longer a tenable approach to meet evolving process requirements, and creative approaches to eliminate defects must be developed to meet these challenges.
This overview will provide process engineers insight into the complexity of filtration to reduce defect variability and downtime. The many factors that impact filtration efficacy will be reviewed, including complete filter design, material selection, membrane morphology, wettability, and fluid dynamics. New technological approaches under consideration will be discussed. Data will be presented to demonstrate promise of these new approaches and where they could lead us in the future.