Stress-strain response of lead-free solder joints in MEMS device using finite element code

摘要

Based on finite element simulation, the stress-strain response of Sn3.8Ag0.7Cu0.03Ce, Sn3.8Ag0.7Cu, Sn0.7Cu solder joints in MEMS device after reflow soldering under thermal cycles loading (-55°C～125°C). It is found that stress-strain can be influenced by the solder materials obviously, the Sn3.8Ag0.7Cu0.03Ce solder joints represents priority property among the three solder materials, and the weakest solder joint can be found in the solder joints array. Based on fatigue life prediction model, combing the data of finite element simulation, the fatigue life of Sn3.8Ag0.7Cu0.03Ce, Sn3.8Ag0.7Cu, Sn0.7Cu solder joints in MEMS device can be calculated, and the fatigue life of Sn3.8Ag0.7Cu0.03Ce solder joint is demonstrated to be the highest of all.