9416752 Mullen This research is intended to advance the understanding of the mechanical behavior of silicon at the micro- and nano-scale levels in order to improve the mechanical reliability of microelectromechanical systems (MEMS). The proposed research seeks to provide a sound fracture mechanics base for polysilicon MEMS devices and a sound materials science base relating processing parameters to polysilicon microstructures and polysilicon microstructures to mechanical behavior. The overall aim is to understand and significantly improve the mechanical reliability of polysilicon MEMS devices by combining the research expertise of applied mechanicians, materials scientists and electrical engineers. This synergistic collaboration will lead to new knowledge that will significantly improve the design, fabrication and utility of MEMS devices. ***