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Title: Shoulder fillet effects in strength distributions of microelectromechanical system components

Abstract

The failure forces and fracture strengths of polysilicon microelectromechanical system (MEMS) components in the form of stepped tensile bars with shoulder fillets were measured using a sequential failure chain methodology. Approximately 150 specimens for each of four fillet geometries with different stress concentration factors were tested. The resulting failure force and strength distributions of the four geometries were related by a common sidewall flaw population existing within different effective stressed lengths. The failure forces, strengths, and flaw population were well described by a weakest-link based analytical framework. Finite element analysis was used to verify body-force based expressions for the stress concentration factors and to provide insight into the variation of specimen effective length with fillet geometry. Monte Carlo simulations of flaw size and location, based on the strength measurements, were also used to provide insight into fillet shape and size effects. The successful description of the shoulder fillet specimen strengths provides further empirical support for application of the strength and flaw framework in MEMS fabrication and design optimization.

Authors:
ORCiD logo [1];  [2];  [3]; ORCiD logo [4]; ORCiD logo [4]
  1. National Inst. of Standards and Technology (NIST), Boulder, CO (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  3. National Inst. of Standards and Technology (NIST), Boulder, CO (United States)
  4. National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1738922
Report Number(s):
SAND-2020-8355J
Journal ID: ISSN 0960-1317; 689903
Grant/Contract Number:  
AC04-94AL85000; NA0003525
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Micromechanics and Microengineering. Structures, Devices and Systems
Additional Journal Information:
Journal Volume: 30; Journal Issue: 12; Journal ID: ISSN 0960-1317
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; strength distributions; flaw populations; polysilicon MEMS; shoulder fillets; fracture

Citation Formats

DelRio, Frank W., Boyce, Brad L., Benzing, Jake T., Friedman, Lawrence H., and Cook, Robert F. Shoulder fillet effects in strength distributions of microelectromechanical system components. United States: N. p., 2020. Web. doi:10.1088/1361-6439/abbf89.
DelRio, Frank W., Boyce, Brad L., Benzing, Jake T., Friedman, Lawrence H., & Cook, Robert F. Shoulder fillet effects in strength distributions of microelectromechanical system components. United States. https://doi.org/10.1088/1361-6439/abbf89
DelRio, Frank W., Boyce, Brad L., Benzing, Jake T., Friedman, Lawrence H., and Cook, Robert F. Fri . "Shoulder fillet effects in strength distributions of microelectromechanical system components". United States. https://doi.org/10.1088/1361-6439/abbf89. https://www.osti.gov/servlets/purl/1738922.
@article{osti_1738922,
title = {Shoulder fillet effects in strength distributions of microelectromechanical system components},
author = {DelRio, Frank W. and Boyce, Brad L. and Benzing, Jake T. and Friedman, Lawrence H. and Cook, Robert F.},
abstractNote = {The failure forces and fracture strengths of polysilicon microelectromechanical system (MEMS) components in the form of stepped tensile bars with shoulder fillets were measured using a sequential failure chain methodology. Approximately 150 specimens for each of four fillet geometries with different stress concentration factors were tested. The resulting failure force and strength distributions of the four geometries were related by a common sidewall flaw population existing within different effective stressed lengths. The failure forces, strengths, and flaw population were well described by a weakest-link based analytical framework. Finite element analysis was used to verify body-force based expressions for the stress concentration factors and to provide insight into the variation of specimen effective length with fillet geometry. Monte Carlo simulations of flaw size and location, based on the strength measurements, were also used to provide insight into fillet shape and size effects. The successful description of the shoulder fillet specimen strengths provides further empirical support for application of the strength and flaw framework in MEMS fabrication and design optimization.},
doi = {10.1088/1361-6439/abbf89},
journal = {Journal of Micromechanics and Microengineering. Structures, Devices and Systems},
number = 12,
volume = 30,
place = {United States},
year = {Fri Nov 06 00:00:00 EST 2020},
month = {Fri Nov 06 00:00:00 EST 2020}
}

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