Anand constitutive model of lead free solder joints in 3D IC device
Anand constitutive relation of SnAgCu and SnAgCu nano Al solders were studied under uniaxial tension, and the constitutive model was used in the finite element simulation to analyze the stress strain response of lead free solder joints in 3D IC devices. The results showed that the nine parameters of the Anand model can be determined from separated constitutive relations and experimental results. Based on Anand model, the finite element method was selected to calculate the stress strain response of lead free solder joints, it was found that in the 3D IC device the maximum stress strain concentrated in the concern solder joints, the stress strain of SnAgCu nano Al solder joints was lower than that of SnAgCu solder joints, which represented that the addition of nano Al particles can enhance the reliability of lead free solder joints in 3D IC devices.