Conduction Path Formation Mechanism of Solderable Polymer Composites with Low-Melting-Point Alloy/High-Melting-Point Alloy Mixed Filler

Abstract

A novel interconnection mechanism using a solderable polymer composite (SPC) with a low-melting-point alloy (LMPA)/high-melting-point alloy (HMPA) mixed filler was proposed to enhance the properties of the LMPA filler and establish a conduction path containing the HMPA filler. To investigate the feasibility of the proposed interconnection mechanism, three types of SPC with a different mixing ratios of LMPA/HMPA filler (100:0, 50:50, and 0:100) were formulated. The SPC with only an HMPA filler showed weak conduction path formation due to excessive curing of the polymer composite before melting of the HMPA filler. In contrast, the SPC with an LMPA/HMPA mixed filler formed a stable and wide conductive path due to the suitable flow-coalescence-wetting behaviors of the molten LMPA filler containing solid-state HMPA filler, which came into effect before excessive curing of the polymer composite.