Patent ID: 6774493
Filing Date: 2004-08-10
Classification: B23K,B32B,C09J,H01L,H05K

Abstract:
An integrated, circuit and substrate assembly comprising:a) an electrical circuit substrate, b) an integrated circuit, coated with a first portion thermosetting polymer encapsulated said coated integrated circuit electrically interconnected to the electrical circuit substrate through solder bumps; and c) a hardened underfill encapsulant which comprises intermixed reaction products of (i) the first portion thermosetting polymer and (ii) a second portion, distinct first the first portion, comprising a fluxing agent, the underfill encapsulant being a hardened adhesive polymer, that chemically immobilizes the fluxing agent mid flux reaction byproducts such thaw the second portion does not appreciably degrade reliability of the integrated circuit assembly.