Patent ID: 7037399
Filing Date: 2006-05-02
Classification: C08G,H01L,Y10T

Abstract:
1. A B-stageable underfill encapsulant, wherein the encapsulant solidifies at a first temperature during the B-stage process to produce a smooth, non-tacky surface on a semiconductor wafer or silicon chip and wherein substantially the entire encapsulant cures at a second temperature that is higher than the first temperature, wherein the encapsulant comprises: a) a thermal curable resin; b) an imidazole-anhydride adduct; c) at least one solvent; d) one or more fluxing agents; and e) optionally, one or more of the group consisting of surfactants, wetting agents, defoaming agents, coupling agents, inorganic fillers, adhesion promoters, flow additives, air release agents, and mixtures thereof, wherein the imidazole-anhydride adduct comprises an adduct of 2-phenyl-4-methyl imidazole and pyromellitic dianhydride.