| 摘要 |
<p>An underfill encapsulant is provided to be used to apply a chip scale package to a substrate, to be B-stageable or to be capable of being formed into film, and to have sufficient flowability to form fillet and to impart good adhesion between a chip and a substrate. The expandable thermoplastic or thermosetting underfill encapsulant is used to encapsulate at least one electronic part(1) adhered to at least one substrate(4) with solders(2) reflowable at reflow temperature. The underfill encapsulant comprises (a) a high-molecular-weight solid resin system including a thermoplastic polymer resin or thermosetting resin, at least one catalyst, and optionally at least one phenoxy-containing compound, (b) at least one expandable filler, and (c) optionally at least one material selected from the group consisting of a surfactant, a coupling agent, a reactive diluent, an air release agent, a flow additive, an adhesion accelerator, a solvent, and mixtures thereof. The underfill encapsulant is expanded at the reflow temperature of the solders or the temperature higher than the reflow temperature.</p> |
