Influence Of Newly Molding Compound Properties On Package Failure During Reflow Soldering Process

Abstract

Surface mount devices (SMDs) are heated up above solder melting temperature during reflow soldering process. If the plastic encapsulant has absorbed moisture, package cracking may occur. In this study, it is proved that the low crosslinking density to be reflected on the low flexural modulus at high temperature is effective for the improvement of package cracking resistance. In addition, as the method to reduce the crosslinking density without decreasing glass transition temperature, it is confirmed the introduction of rigid structural segments to the molecules of matrix resins is available.