AVS 56th International Symposium & Exhibition
    Tribology Focus Topic Tuesday Sessions
       Session TR+SS-TuA

Paper TR+SS-TuA8
Molecular Dynamics Simulations of Nanoindentation of Si/SiO2 Systems using the Charge Optimized Many-Body (COMB) Potential

Tuesday, November 10, 2009, 4:20 pm, Room B2

Session: Surface Science for Tribology
Presenter: T.R. Shan, University of Florida
Authors: T.R. Shan, University of Florida
B. Devine, University of Florida
S.R. Phillpot, University of Florida
S.B. Sinnott, University of Florida
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Oxides and carbides, such as SiO2, Al2O3, HfO2 and SiC, are widely used together with Si in many high-performance electronic devices, including metal-oxide-semiconductor (MOS) devices/junctions and gate stacks. The lack of precise control over mechanical properties can lead to the degradation of these materials. It is therefore critical to understand the nanometer-scale mechanical properties of materials or complex systems being considered for use in electronic devices. Since nanoindentation has been established as a primary tool for investigating the mechanical behavior of small volumes of materials, classical molecular dynamics simulation is used to examine the nanoindentation of Si/SiO2 interfacial systems. Because these systems consist of heterogeneous interface with significant changes in bonding as one crosses from one side of the interface to the other, the empirical charge optimized many-body (COMB) potential is used to model the structural evolution, mechanical response and charge transfer of Si/SiO2 interfacial systems under the influence of a nanometer-scale indenter. The COMB potential allows for dynamic charge transfer between atoms and across interfaces, and does a good job in describing covalent and ionic bonding in these materials. Aspects of the Si/SiO2 interface during nanoindentation, including dislocation formation and the mechanisms by which fracture occurs, will also be addressed. We gratefully acknowledge the support of the National Science Foundation through grant DMR-0426870.