Further considerations on the high-cycle fatigue of micron-scale polycrystalline silicon
نویسندگان
چکیده
Bulk silicon is not susceptible to high-cycle fatigue but micron-scale silicon films are. Using polysilicon resonators to determine stress-lifetime fatigue behavior in several environments, oxide layers are found to show up to four-fold thickening after cycling, which is not seen after monotonic loading or after cycling in vacuo.We believe that the mechanism of thin-film silicon fatigue is ‘‘reaction-layer fatigue”, involving cyclic stress-induced thickening of the oxide and moisture-assisted cracking within this layer. Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
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