Reliability study on thermal cycling of QFP device solder joints based on morphological optimisation

As a research method with low cost and high accuracy, finite element simulation is widely used in various fields. However, there are still some difficulties in obtaining accurate initial model in some researches. In this paper, Surface Evolver software is used to calculate the initial solder joint model of QFP device by energy minimization principle, and the model is tested experimentally. Then, the solder joint model was imported into the finite element software to establish the QFP device model, and the thermal cycle simulation test at -55-150°C was carried out to obtain the mechanical properties of the solder joint. Finally, the fatigue life prediction model is used to calculate the life of solder joints.