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Title: Unveiling the Apparent “Negative Capacitance” Effects Resulting from Pulse Measurements of Ferroelectric-Dielectric Bilayer Capacitors
Apparent ‘Negative Capacitance’ (NC) effects have been observed in some ferroelectric-dielectric (FE-DE) bilayers by pulse measurements, and the associated results have been published that claim to be direct evidence to support the quasi-static ‘negative capacitance’ (QSNC) idea. However, the ‘NC’ effects only occur when sufficiently high voltage is applied, and even exist in stand-alone FE capacitors. These results contradict the QSNC theory, as it predicts that once stabilized (requires a DE layer), the FE remains in the ‘NC’ state regardless of the applied voltage. In this letter, by the use of Nucleation-Limited-Switching (NLS) model, we present our results obtained from simulation of pulse measurements on samples that are similar to the published ones. The simulation results indicate that reverse polarization switching occurs upon the falling edge of the pulses, which leads to the apparent hysteresis-free NC effect. This work provides an alternative interpretation of the experimental results without invoking the QSNC theory.  more » « less
Award ID(s):
1941316
NSF-PAR ID:
10207151
Author(s) / Creator(s):
; ; ;
Editor(s):
Naeemi, A.J.
Date Published:
Journal Name:
IEEE electron device letters
Volume:
41
Issue:
10
ISSN:
1558-0563
Page Range / eLocation ID:
1492-95
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Acknowledgement

    This work was supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.

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