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arXiv · 1602.01204

Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors

Suhas Kumar·Catherine E. Graves·John Paul Strachan·Emmanuelle Merced Grafals·Arthur L. David Kilcoyne·Tolek Tyliszczak·Johanna Nelson Weker·Yoshio Nishi·R. Stanley Williams
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Abstract

Oxygen migration in tantalum oxide, a promising next-generation storage material, is studied using in-operando x-ray absorption spectromicroscopy and is used to microphysically describe accelerated evolution of conduction channel and device failure. The resulting ring-like patterns of oxygen concentration are modeled using thermophoretic forces and Fick diffusion, establishing the critical role of temperature-activated oxygen migration that has been under question lately.

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Suhas Kumar, Catherine E. Graves, John Paul Strachan, Emmanuelle Merced Grafals, Arthur L. David Kilcoyne, Tolek Tyliszczak, Johanna Nelson Weker, Yoshio Nishi, R. Stanley Williams. 2016-02-03. Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors. https://doi.org/10.1002/adma.201505435

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