Patent ID: 6187248
Filing Date: 2001-02-13
Classification: C08J,H01B,H01L

Abstract:
A process for producing a nanoporous polymer film of no greater than 10 micron thickness having low dielectric constant value, comprising the steps of:(a) providing a polymer in a solution with at least two solvents for said polymer in which a lowest boiling solvent and a highest boiling solvent have a difference in their respective boiling points of approximately 50.degree. C. or greater;(b) forming a film of said polymer in solution with at least said two solvents on a substrate;(c) removing a predominant amount of said lowest boiling solvent;(d) contacting said film with a fluid which is a non-solvent for said polymer, but which is miscible with said at least two solvents to induce phase inversion in said film;(e) forming an average pore size in said film in the range of less than 30 nanometers.