An Experimental Investigation of a Flexible Sintered Silver Joint for Micro-Joining Based on a Design of Experiments

Abstract

The increasing electrification of vehicles requires the use of ever higher voltages and electrical power. The thermal stresses to which the assembly joints of electronic chips are subjected are becoming increasingly severe. As a result, thermal stresses acting on the electronic assembly, and particularly on the electrical interconnections, are becoming increasingly severe. The objective of this study is to create, characterize and optimize the structure and properties of a porous silver sintered joint using the design of experiments (DoE) method. Joints consisting of a porous network of silver particles are obtained, showing remarkable flexibility allowing for thermal stresses accommodation and having sufficient tensile strength to ensure a correct bonding of the components. Depending on the selected levels for the sintering process parameters, the microscopy analysis shows a transition of the mode of rupture from the silver layer to the intermetallic compounds forming at the interface with the substrate.