Temperature dependent mechanical properties of inter-metallic compounds in nano-solder joints

Abstract

SnAgCu (SAC) alloys has become the topic of interest in recent days, as it shows great potential to be alternate to lead-based solders, the use of which is being discontinued for environmental issues. Intermetallic compounds (IMC) form in the solder joints which reduces the strength and other properties thus reducing the reliability of microprocessor components. To investigate this behavior, intermetallic compounds were modeled at nanoscale. Properties of three intermetallic compounds were investigated which are Ag3Sn, Cu3Sn and Cu6Sn5. The variation of mechanical properties the ultimate tensile strength, yield strength and Young’s modulus with the change of temperature were thoroughly observed. Also, the coefficient of thermal expansion was determined for these three different compounds. The mechanical properties of these three compounds were compared to find out which of these poses the greater threat to the solder joints. All the simulations were done by molecular dynamics software LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) and the structures of the IMCs were built by VNL (Virtual NanoLab). Molecular dynamics approach was used to model the interaction between molecules under various temperatures.SnAgCu (SAC) alloys has become the topic of interest in recent days, as it shows great potential to be alternate to lead-based solders, the use of which is being discontinued for environmental issues. Intermetallic compounds (IMC) form in the solder joints which reduces the strength and other properties thus reducing the reliability of microprocessor components. To investigate this behavior, intermetallic compounds were modeled at nanoscale. Properties of three intermetallic compounds were investigated which are Ag3Sn, Cu3Sn and Cu6Sn5. The variation of mechanical properties the ultimate tensile strength, yield strength and Young’s modulus with the change of temperature were thoroughly observed. Also, the coefficient of thermal expansion was determined for these three different compounds. The mechanical properties of these three compounds were compared to find out which of these poses the greater threat to the solder joints. All the simulations were done by molecular dynamics software LAMMPS (Large-scale ...