In this thesis the temperature hysteresis of Flip-Chip MEMS-Microphones will be presented by experimental measurements and simulation. The electrical connection of these Flip-Chip MEMS-Microphones is realised via solder bumps with the solder alloy SAC 387. The creep behaviour of the solder bumps is the cause of the temperature hysteresis. In this thesis the creep behaviour was determined by a mathematical average model and experimental research with a nanoindenter directly at the solder bumps. The two determined creep rates differ themselves in their magnitudes. In order to decide which creep rates will be chosen for further simulations, the behaviour of the microphone was simulated with both creep rates to see which one reflects the behaviour more appropriately. The simulations were then compared to experimental measurements. The simulations were performed with finite element analysis by the free and open-source simulation program Code-Aster. Calculations, which have been executed to verify Code-Aster, have shown that Code-Aster provides good and reliable results. Therefore, the compared simulations with both creep rates have shown that the creep rate determined by the nanoindenter reflects the microphone behaviour the best. The creep rate determined by the nanoindenter was used for further simulations. With this model the influence of the shape of the solder bumps on the temperature hysteresis could be analysed. First the height of the solder bumps has been varied and the effect on the temperature hysteresis has been simulated. The temperature hysteresis decreases with the increasing height of the solder bumps. It was then simulated how the curvature of the solder joints affects the temperature hysteresis. The curvature of the solder bumps has a negligible influence on the temperature hysteresis.
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