Lithography

Lithography coating needs to be free of particles, metals, organic materials and bubbles. To achieve defect free coatings, filters must have very high retention while minimizing any source for contamination. Pall lithography filters use a variety of membrane materials to effectively eliminate contaminants and defects in lithography process chemicals. They reduce chemical waste and start-up time associated with filter changes, and offer finer removal characteristics and superior initial cleanliness over previous products.

Several factors must be considered in the selection of the appropriate microlithographic filter. Bulk filters and point-of-use (POU) dispense filters prevent the deposition of unwanted particles. The POU filter is an integral part of any precision dispense system; therefore, careful selection of this filter is necessary to reduce defects on the wafer surface. Optimized design for point of use dispense, a swept flow path design, and excellent purging characteristics are all crucial.

In addition to particle and gel removal, minimization of microbubble formation, reduced chemical consumption and good compatibility are all key for POU filter selection. Chemically compatible with various lithography solvents, including PGMEA, PGME, EL, GBL and cyclohexanone, Pall’s optimized filter designs reduce chemical usage during start-up and use large surface areas. As a result, low differential pressures maximize gel removal efficiency and minimize microbubble formation. Low operating pressure ensures the filter will not cause photochemicals to outgas as they are dispensed from high pressure to low pressure during process.

Benefits:

• Decreased equipment downtime
• Higher yields
• Increased chemical and dispense nozzle life
• Variety of membranes for any photolithography application
• Rapid Venting Design (Minimal Microbubble Production)
• Reduced chemical waste

Our lithography filter technologies streamline manufacturing operations, decrease downtime of dispense systems, and decrease wafer surface defects. For more information, contact a Pall expert for purchase information.