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Updated: Sep 23, 2025

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx
Published on: May 13, 2020
Mechanism and Impact of Bipolar Current Voltage Asymmetry in Computational Phase-Change Memory
Syed Ghazi Sarwat1, Manuel Le Gallo1, Robert L Bruce2
1IBM Research-Europe, Säumerstrasse 4, Rüschlikon, 8803, Switzerland.
Abstract:
Nanoscale resistive memory devices are being explored for neuromorphic and in-memory computing. However, non-ideal device characteristics of read noise and resistance drift pose significant challenges to the achievable computational precision. Here, it is shown that there is an additional non-ideality that can impact computational precision, namely the bias-polarity-dependent current flow. Using phase-change memory (PCM) as a model system, it is shown that this "current-voltage" non-ideality arises both from the material and geometrical properties of the devices. Further, we discuss the detrimental effects of such bipolar asymmetry on in-memory matrix-vector multiply (MVM) operations and provide a scheme to compensate for it.
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