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DOE OSTI · 3395438

Maximizing dynamic range and performance of anatase TiO 2 ECRAM through structure and programming

Alvarez, Ana I. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)]·Theodoru, Stefan A. [University of Maryland, College Park, MD (United States)]·Pollard, Travis P. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)]·Boltersdorf, Jonathan [DEVCOM Army Research Laboratory, Adelphi, MD (United States)]·Sarney, Wendy L. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)]·Hoerauf, John M. [University of Maryland, College Park, MD (United States)]·Kozen, Alexander C. [University of Maryland, College Park, MD (United States); University of Vermont, Burlington, VT (United States)]·Grew, Kyle N. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)]·Rubloff, Gary W. [University of Maryland, College Park, MD (United States)]·Talin, Albert Alec [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:000000021102680X)·Schroeder, Marshall A. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)] (ORCID:0000000281602833)
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Abstract

Here, in this study, we investigate the structure-dependent modulation characteristics of all-solid-state three-terminal electrochemical random-access memory (ECRAM) based on an anatase Li x TiO 2 channel. By directly comparing “asymmetric” and “symmetric” ECRAM device architectures, we reveal significant insight into the impact of a non-zero gate-drain open-circuit voltage and its influence on voltage vs. current-controlled gating. We also explore the impact of potentiation/depression write parameters on the symmetry, linearity, and dynamic range of the device response. Together, initial results from optimizing structure and programming approaches yielded unprecedented G max /G min ratios of >1,000 for ECRAM and hundreds of tunable memory states with excellent linearity and symmetry. Simulations based on these ECRAM devices further illustrate the promise of this analog memory technology, achieving near 2% classification error in the MNIST digit recognition benchmark for a range of training parameters compared to a theoretical best of 1.66% and outperforming other device models extracted from the literature.

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Alvarez, Ana I. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)], Theodoru, Stefan A. [University of Maryland, College Park, MD (United States)], Pollard, Travis P. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)], Boltersdorf, Jonathan [DEVCOM Army Research Laboratory, Adelphi, MD (United States)], Sarney, Wendy L. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)], Hoerauf, John M. [University of Maryland, College Park, MD (United States)], Kozen, Alexander C. [University of Maryland, College Park, MD (United States); University of Vermont, Burlington, VT (United States)], Grew, Kyle N. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)], Rubloff, Gary W. [University of Maryland, College Park, MD (United States)], Talin, Albert Alec [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)] (ORCID:000000021102680X), Schroeder, Marshall A. [DEVCOM Army Research Laboratory, Adelphi, MD (United States)] (ORCID:0000000281602833). 2026-07-09. Maximizing dynamic range and performance of anatase TiO 2 ECRAM through structure and programming. https://doi.org/10.1016/j.device.2026.101223

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