This paper introduces a series of single pass reflow encapsulantsthat requires no post curing after solder bump reflow. Acting as a fluxand an encapsulant, this product performs two functions. First, thematerial activates the solder bump and metallic bond pad during solderreflow to establish the interconnection between the die and substrate.Second, while this material is being cured, it forms a mechanical bondbetween the surface of the die and substrate. This product allowsprocessing normal surface mount component packages concurrently withflip chip, CSPs or BGAs under the standard surface mount reflow-profile.Such a process eliminates capillary underfilling and curing time. Theproduct's solderability is robust and high yield; the parts are reliableafter thermal shock testing. We have employed DSC, TMA, DMA and sheartest techniques to investigate the properties of the material. Theseproperties include influence of filler loading level, curing reflowprofile, percentage cure, glass transition temperature (Tg), coefficientof thermal expansion (CTE), modulus and die shear adhesion
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