A study on inter-metallic compound formation and structure of lead free SnAgCu solder system

Abstract

This paper characterizes the effect of various Sn-Ag-Cu solder compositions towards shear strength and melting behavior. Shear strength is measured by Dage which is representative of the inter-metallic compound (IMC) strength between the solder and solder clad of a C5 bump. Further study on melting properties will be obtained by Differential Scanning Calorimetry (DSC). It was found that 1wt%Ag 0.5wt%Cu has larger melting range compared to 3 & 4wt%Ag 0.5wt%Cu which could contribute to IMC growth. Relatively, ball shear results shows that shear strength increases with Ag wt% content. A correlation between melting range and shear results made in this study pointed to 3.8wt%Ag0.5wt%Cu having the most favorable results. © 2006 IEEE.