This study presents a first passage based analysis of probabilistic failure of polycrystalline silicon (poly-Si) MEMS structures. The model takes into account both the autocorrelated random strength field and the random stress field. The model is formulated based on the concepts of stationary and non-stationary stochastic processes. It is shown that the model agrees well with the measured strength distributions of uniaxial tensile poly-Si MEMS specimens of different sizes. The present model predicts strong size effects on both the strength distribution and the mean structural strength. An approximate mean size effect equation is developed based on asymptotic matching. The present model is shown to be a generalization of the classical weakest-link statistical model, and it provides a physical interpretation of the material length scale of the weakest-link model.
|Original language||English (US)|
|Title of host publication||ICF 2017 - 14th International Conference on Fracture|
|Editors||Emmanuel E. Gdoutos|
|Publisher||International Conference on Fracture|
|Number of pages||2|
|State||Published - 2017|
|Event||14th International Conference on Fracture, ICF 2017 - Rhodes, Greece|
Duration: Jun 18 2017 → Jun 20 2017
|Name||ICF 2017 - 14th International Conference on Fracture|
|Conference||14th International Conference on Fracture, ICF 2017|
|Period||6/18/17 → 6/20/17|
Bibliographical noteFunding Information:
The authors would like to acknowledge the financial support of the U.S. National Science Foundation under grant CMMI-1361868.