Multimillion atom simulations of nanostructured materials on parallel computers - Sintering and consolidation, fracture, and oxidation

Multiresolution molecular-dynamics approach for multimillion atom simulatio ns has been used to investigate structural properties, mechanical failure i n ceramic materials, and atomic-level stresses in nanoscale semiconductor/c eramic mesas (Si/Si3N4) Crack propagation and fracture in silicon nitride, silicon carbide, gallium arsenide, and nanophase ceramics are investigated. We observe a crossover from slow to rapid fracture and a correlation betwe en the speed of crack propagation and morphology of fracture surface. A 100 million atom simulation is carried out to study crack propagation in GaAs. Mechanical failure in the Si/Si3N4 interface is studied by applying tensil e strain parallel to the interface. Ten million atom molecular dynamics sim ulations are performed to determine atomic-level stress distribtions in a 5 4 nm nanopixel on a 0.1 mu m silicon substrate. Multimillion atom simulatio ns of oxidation of aluminum nanoclusters and nanoindentation in silicon nit ride are also discussed.