Multi-scale Analysis of MEMS Sensors Subject to Drop Impacts

Sensors

Stefano Mariani¹  Aldo Ghisi¹  Alberto Corigliano¹ 

[1] Dipartimento di Ingegneria Strutturale, Politecnico di Milano Piazza L. da Vinci 32, 20133 Milano (Italy). E-mails:

关键词: polysilicon MEMS;    drop test;    multi-scale finite element analysis;   

DOI  :  10.3390/s7081817

来源: mdpi

【 摘 要 】

The effect of accidental drops on MEMS sensors are examined within the framework of a multi-scale finite element approach. With specific reference to a polysilicon MEMS accelerometer supported by a naked die, the analysis is decoupled into macro-scale (at die length-scale) and meso-scale (at MEMS length-scale) simulations, accounting for the very small inertial contribution of the sensor to the overall dynamics of the device. Macro-scale analyses are adopted to get insights into the link between shock waves caused by the impact against a target surface and propagating inside the die, and the displacement/acceleration histories at the MEMS anchor points. Meso-scale analyses are adopted to detect the most stressed details of the sensor and to assess whether the impact can lead to possible localized failures. Numerical results show that the acceleration at sensor anchors cannot be considered an objective indicator for drop severity. Instead, accurate analyses at sensor level are necessary to establish how MEMS can fail because of drops.

【 授权许可】

Unknown   
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