Patent ID: 7041771
Filing Date: 2006-05-09
Classification: B23K,C08G,C08L,H01L,H05K,Y10T

Abstract:
1. An encapsulant for electrically connecting a metal bond site of a first electrical component to a metal bond site of a second electrical component with solder and for forming an encapsulant encased electrical solder connection between said first and second components at solder reflow conditions, comprising: a) a thermosetting epoxy resin; b) a cross-linking agent for said resin that also acts as a fluxing agent that removes oxide coatings from the surface of said first and second electrical components below the solder melt temperature of said solder, and c) a tin octoate catalyst for catalyzing cross-linking of said thermosetting resin with said cross-linking agent, the peak exotherm of said mixture of catalyst, thermosetting resin, and cross-linking agent as measured using DSC at a ramp rate of 10° per minute being at or above the solder melting point whereby the gel point of said cross-linked thermosetting resin is reached after solder melt, wherein the exothermic activity as measured using DSC is initiated at a temperature no lower than 40° C. below the solder melting point.