Electromigration Response of Microjoints in 3DIC Packaging Systems

TL;DR

This paper investigates electromigration effects in microjoints of 3DIC packaging, analyzing vacancy clustering, intermetallic growth, and potential failure mechanisms through kinetic and computational modeling.

Contribution

It introduces a multi-phase-field approach to study electromigration-induced intermetallic growth and vacancy clustering in low-volume solder microjoints in 3DICs.

Findings

Faster intermetallic growth in the anode layer.

Vacancy saturation leads to microvoid formation.

Electromigration can cause ductile failure in microjoints.

Abstract

In multilevel 3D integrated packaging, three major microstructures are viable due to the application of low volume of solders in different sizes, and/or processing conditions. Thermodynamics and kinetics of binary compounds in Cu/Sn/Cu low volume interconnection is taken into account. We show that current crowding effects can induce a driving force to cause excess vacancies saturate and ultimately cluster in the form of microvoids. A kinetic analysis is performed for electromigration mediated intermetallic growth using multi-phase-field approach. Faster growth of intermetallic compounds (IMCs) in anode layer in the expense of shrinkage of cathode IMC layer in shown. This work paves the road for computationally study the ductile failure due to formation of microvoids in low volume solder interconnects in 3DICs.