abstract
We studied the stability of the mechanical properties and the fatigue endurance of Gd-doped ceria (CGO), which is a promising electromechanically active material for microelectromechanical systems (MEMS). Specifically, the fracture strength and long-term operation of plate-type circular (2 mm diameter) thermal actuators made of approximate to 1.15 mu m thick Ce0.95Gd0.05O1.975 (CGO5) were investigated. Excitation voltage of 10 V at the frequency range between 1 and 2.1 MHz induces Joule heating effect that can generate an inplane strain of approximate to 0.1 %. The operation temperature ranged from 25 degrees C to 80 degrees C and the temperature shift, caused by the AC heating, was about 80 K at 10 V. Critical fracture was found to occur at out-of-plane displacements between similar to 35 and similar to 42 mu m, which corresponds to the average bending stress of similar to 44 MPa at the center of the plate. During long-term operation, the actuators exhibit gradual decrease in the response, probably due to contact degradation. However, structural damage or mechanical fatigue was not found even after 10(7) cycles at a stress level of similar to 30 % of the critical fracture strength. (C) 2020 Elsevier B.V. All rights reserved.
keywords
ELECTROSTRICTION; TOUGHNESS; FILMS; PURE
subject category
Engineering; Instruments & Instrumentation
authors
Mishuk, E; Ushakov, A; Shklovsky, J; Krylov, S; Shacham-Diamand, Y; Shur, VY; Kholkin, A; Lubomirsky, I
our authors
Andrei Kholkin
Retired Researcheracknowledgements
This work was supported in part by the Israeli Ministry of Science and Technology grant No 3-12421 and #12421-3, the program of Israel-Russian Federation Scientific Collaboration. This work is part of the BioWings project, which has received funding from the European Union's Horizon 2020 under the Future and Emerging Technologies FET program with a grant agreement No 801267. This research received funding from the Minerva Center for SelfRepairing Systems for Energy & Sustainability and it is made possible in part by the historic generosity of the Harold Perlman Family. The DRIE unit used for this research was purchased with the Israel Science Foundation Grant #2366/17.