DFG-Forschungszentrum "Mathematik für Schlüsseltechnologien - MATHEON": Macroscopic models for precipitation in crystalline solids (Teilprojekt C 14)

Precipitation and subsequent growth of droplets of a new phase in a crystalline solid due to stress assisted diffusion can lead to significant deterioration of the desired properties of the crystal. One example is the formation of arsenic liquid droplets in a semi-isolating galliumarsenid crystal, which is used in the manufacturing of opto-electronic devices. The key question is how, by changing the model parameters, to either prevent precipitation or, if it occurs, to limit it to a homogeneous distribution of small precipitates. The latter is however difficult, since precipitation preferably occurs at point defects of dislocations. The goal of the project is to derive effective macroscopic models from a thermodynamic microscopic description and to efficiently simulate the resulting models.