Modeling of void formation in phase change memory devices
An empirical, versatile finite-element model is developed to predict void formation in as-deposited or melt-quenched amorphous Ge2Sb2Te5 during annealing. This model incorporates void formation with nucleation and growth of the crystals along with thermal models that capture laser heating of the nano-structures during device fabrication. Modeling of void formation during Joule heating or furnace annealing can be implemented in a similar way. The modeling results are compared to example experimental results obtained from pore-cell phase change memory structures.