Patent ID: 7442303

Claim:
A method for making a monolithic polymeric filter membrane comprising at least a filter layer including micron-scale precision-shaped pores and a support layer including a precision-shaped support structure for the filter layer, the method comprising: providing a polymeric film having first and second sides; forming the filter membrane layer by removing selected material from the first side of the polymeric film to define the precision-shaped micron-scale pores of the filter layer; and forming the support structure layer by removing selected material from the second side of said polymeric film to define the precision-shaped porous support structure, the pores communicating with the porous support structure to allow the passage of filtrate therethrough, and further comprising at least one of said filter layer and support layer being formed by: providing a polymeric film that is of polyimide material applying a metallic film to one surface of said polyimide film, applying a photoresist material to said metallic film, creating a first pattern on said photoresist layer to define micron scale pores or support structure and removing selected material from said photoresist layer; removing material from said metallic film in the areas where said photoresist material has been removed; and removing selected material from the polyimide film in the areas where the metallic film has been removed to define the pores or support structure; removing any remaining photoresist material and the metallic film from the polyimide film.