Mechanical Characterization of Polysilicon MEMS: A Hybrid TMCMC/POD-Kriging Approach

Authors

Ramin Mirzazadeh, Politecnico di MilanoFollow
Saeed Eftekhar Azam, University of Nebraska-LincolnFollow
Stefano Mariani, Politecnico di MilanoFollow

ORCID IDs

https://orcid.org/0000-0002-1157-2982 Ramin Mirzazadeh

https://orcid.org/0000-0001-5111-9800 Stefano Mariani

Document Type

Article

Date of this Version

4-17-2018

Citation

Sensors 2018, 18, 1243; doi:10.3390/s18041243

www.mdpi.com/journal/sensors

Comments

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license

Abstract

Microscale uncertainties related to the geometry and morphology of polycrystalline silicon films, constituting the movable structures of micro electro-mechanical systems (MEMS), were investigated through a joint numerical/experimental approach. An on-chip testing device was designed and fabricated to deform a compliant polysilicon beam. In previous studies, we showed that the scattering in the input–output characteristics of the device can be properly described only if statistical features related to the morphology of the columnar polysilicon film and to the etching process adopted to release the movable structure are taken into account. In this work, a high fidelity finite element model of the device was used to feed a transitional Markov chain Monte Carlo (TMCMC) algorithm for the estimation of the unknown parameters governing the aforementioned statistical features. To reduce the computational cost of the stochastic analysis, a synergy of proper orthogonal decomposition (POD) and kriging interpolation was adopted. Results are reported for a batch of nominally identical tested devices, in terms of measurement error-affected probability distributions of the overall Young’s modulus of the polysilicon film and of the overetch depth.