Patent ID: 6402876
Filing Date: 2002-06-11
Classification: G03F,H01L,H01R,H05K

Abstract:
A method of forming an anisotropic conductive film comprising a monolayer non-random array of substantive particles, said method comprising the steps of:(a) applying to a substrate a curable ferrofluid composition, comprising: (i) a colloidal suspension of ferromagnetic particles in a non-magnetic carrier liquid, and (ii) substantive particles, said substantive particles having a particle size on at least one dimension thereof of at least 1 micrometer, so as to form a monolayer of substantive particles on the substrate; (b) exposing the substantive particle-containing ferrofluid composition to a source of energy suitable and for a sufficient time to polymerize a layer of the curable ferrofluid composition having a thickness of no more than 50% of the height of the largest substantive particles, while the substantive particles are exposed to a magnetic field to form a non-random array thereof; (c) removing uncured curable ferrofluid composition; (d) applying an adhesive film over the surface of the non-random arrayed substantive particles, opposite to the layer of cured ferrofluid composition; (e) pressing the substantive particles into the adhesive film; (g) separating away from the layer of cured ferrofluid composition the adhesive film with the non-random arrayed substantive particles adhered thereto; and (h) applying a penetrable film-forming material, to fill the interstitial spaces in the non-random arrayed substantive particles adhered to the adhesive film, and to cover the substantive particles.