Numerical Investigation on Self-Organized Interconnection Using Anisotropic Conductive Adhesive with Low Melting Point Alloy Filler

Abstract

The present study is devoted to develop a new simulation code for the numerical investigation on coalescence characteristics in self-organized interconnection using anisotropic conductive adhesive (ACA) with low melting point alloy (LMPA) fillers. In particular, this article examines the coalescence mechanism during ACA process for different resin viscosity, particle volume fractions, and provides estimated results of conduction path growth fraction for different conditions. Starting from the motion equation of filler particles, moreover, a theoretical approach is presented to find out dominant factors affecting the formation of interconnection. The new simulation code is based on the finite volume method with the use of the continuum surface force (CSF) model and the cubic interpolated propagation (CIP) method. It is confirmed that conduction path formation depends on volume fraction, viscosity, and surface tension during the process. It is also found that the pressure-driven force effect becomes not dominant in the path formation at high resin viscosity and high filler density, the particle drift velocity becomes slow due to the increase in resin viscosity, conduction path growth fraction increases with the volume fraction, and the time for path formation is shorter with the increase of the volume fraction.