Patent ID: 8597785
Filing Date: 2013-12-03
Classification: C08L,C09D,C09J,H05K,Y10T

Abstract:
1. An adhesive film comprising a flux-active compound having a carboxyl group and/or a phenolic hydroxyl group, an epoxy-resin, a phenol novolac curing agent, and a film-forming resin; wherein the flux-active compound is present in an amount of from 1% by weight or more and 30% by weight or less based on the total weight of the adhesive film; wherein the phenol novolac curing agent is present in an amount of from 5% by weight or more and 30% by weight or less based on the total weight of the adhesive film; wherein said film-forming resin comprises acrylic rubber having at least one functional group selected from the group consisting of a nitrile group, an epoxy group, a hydroxy group, and a carboxyl group, wherein said adhesive film has a copper-oxide reduction rate of 70% or more, the copper-oxide reduction rate being represented by equation (1), and being measured by attaching said adhesive film to the surface of a copper plate which is oxidized and by reducing the copper plate at 230° C. for one minute in the air, and wherein said adhesive film has a solder wet spread rate of 40% or more, the solder wet spread rate being represented by equation (2), and being measured by placing a solder ball which consists of Sn-3.0Ag-0.5Cu and which has a diameter of 500 μm over said adhesive film, by heating the solder ball at a temperature of 30° C. higher than a melting point of said solder ball for 20 seconds following ASTM B 545 to wet-spread the solder ball, and by measuring a thickness of the solder ball after the wet-spreading,