Filter sheet and process for purifying photoresist composition employing the filter sheet
AssigneeCuno Incorporated
InventorsKenneth C. Hou, Eugene A. Ostreicher, Richard D. Sale
Life of this patent
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Abstract
A filter sheet is provided which comprises a self-supporting fibrous matrix having immobilized therein particulate filter aid and particulate ion exchange resin, wherein said particulate filter aid and particulate ion exchange resin are distributed substantially uniformly throughout a cross-section of said matrix. A process for removing ionic impurities from a photoresist solution is also provided which comprises passing the photoresist solution through said filter sheet to remove ionic impurities therefrom.
Claims32
A process for removing dissolved ionic impurities from a photoresist, the photoresist consisting essentially of a light-sensitive compound and a film-forming polymer, the process comprising:
- passing the photoresist through a filter sheet comprising a self-supporting fibrous matrix having immobilized therein particulate filter aid and ion exchange resin particles, wherein said particulate filter aid and ion exchange resin particles are distributed substantially uniformly throughout a cross-section of said matrix.
Dependencies are inferred from the claim text.