Dislocation activities in semiconductor thin film systems

Microstructural dislocation defects play a central role in the fabrication, performance and reliability of microelectronic devices. A discrete dislocation dynamics model is developed to establish the equations of motion for three-dimensional interacting dislocation loops in the semiconductor thin film - substrate system. The film is assumed to be an elastic thin layer and is perfectly bonded with another elastic substrate. The stress fields of threading and misfit dislocation loops are first calculated as an essential ingredient in the dislocation dynamics method. Dislocation loops are discretized into segments, each of which is represented by a parametric space curve of specific shape functions and associated degree of freedom. The simulation of dislocation activities is applied to several issues related to threading dislocation growth, interaction of dislocation loops with surface and interface. Comparisons between the present prediction and experimental observation are also presented.