Research staff scientist, Princeton University, Princeton, NJ
Engineer, Natick, MA
Director, Natick, MA
Professor, Princeton University, Princeton, NJ
Pages: 13 Published: Jan 2001
This paper presents the results of an experimental study of surface topology evolution that leads to crack nucleation and propagation in silicon MEMS structures. Following an initial description of the unactuated surface topology and nanoscale microstructure of polysilicon, the micromechanisms of crack nucleation and propagation are elucidated via in situ atomic force microscopy examination of cyclically actuated comb-drive structures fabricated from polysilicon. It is found that the surface of the polycrystalline silicon MEMS undergoes topological changes that lead to elongation of surface features at the highest tensile point on the surface. A smoothing trend is also observed after a critical stress level is reached.
surface, topology, fatigue, Si MEMS, AFM, morphology
Paper ID: STP10976S