A custom micro-mechanical test system was constructed using off-the-shelf components to characterize the mechanical properties of microshutters. Microshutters are rectangular microelectromechanical apertures which open and close about a narrow torsion bar hinge. Displacement measurements were verified using both capacitive and digital image correlation techniques. Repeatable experiments on Si₃N₄ cantilever beams verified that the test system operates consistently. Using beam theory, the modulus of elasticity of the low stress Si₃N₄ was approximately 150 GPa, though significant uncertainty exists for this measurement due primarily to imprecise knowledge of the cantilever thickness. Tests conducted on microshutter arrays concluded that reducing the Si₃N₄ thickness from 250 nm to 500 nm reduces the torsional stiffness by a factor of approximately four. This is in good agreement with analytical and finite element models of the microshutters.

Date Published: 28 August 2014
PDF: 8 pages
Proc. SPIE 9170, Nanoengineering: Fabrication, Properties, Optics, and Devices XI, 917009 (28 August 2014); doi: 10.1117/12.2060449

Published in SPIE Proceedings Vol. 9170:
Nanoengineering: Fabrication, Properties, Optics, and Devices XI
Eva M. Campo; Elizabeth A. Dobisz; Louay A. Eldada, Editor(s)