Wet particle reduction during filter installation and start-up aligns closely with initiatives to reduce both chemical
consumption and preventative maintenance time. The present study focuses on the effects of filter materials cleanliness
on wet particle defectivity through evaluation of filters that have been treated with a new enhanced cleaning process
focused on organic compounds reduction. Little difference in filter performance is observed between the two filter types
at a size detection threshold of 60 nm, while clear differences are observed at that of 26 nm. It can be suggested that
organic compounds can be identified as a potential source of wet particles. Pall recommends filters that have been
treated with the special cleaning process for applications with a critical defect size of less than 60 nm. Standard filter
products are capable to satisfy wet particle defect performance criteria in less critical lithography applications.