Method of producing a sheet comprising through pores and the application thereof in the production of micronic and submicronic filters

摘要

The method comprises the following steps: preparing a sheet having thickness of 5 mum to a few tens of micrometers, suitable for being etched by a lithographic operation; making a mask on a face of the sheet, the mask presenting etching selectivity S of at least 5; depositing a layer of photosensitive resin on the mask; making through holes in the layer of resin by photolithography; etching through the mask via the pores in the layer of resin; and anisotropically etching through the sheet from the pores in the mask in order to make pores in the sheet having an aspect ratio greater than 5. The invention is applicable to fabricating micron and sub-micron filters.