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Title: On the bipolar resistive-switching characteristics of Al₂O₃- and HfO₂-based memory cells operated in the soft-breakdown regime

Abstract

In this article, we investigate extensively the bipolar-switching properties of Al₂O₃- and HfO₂-based resistive-switching memory cells operated at low current down to <1 μA. We show that the switching characteristics differ considerably from those typically reported for larger current range (>15 μA), which we relate as intrinsic to soft-breakdown (SBD) regime. We evidence a larger impact of the used switching-oxide in this current range, due to lower density of oxygen-vacancy (V{sub o}) defects in the SBD regime. In this respect, deep resetting and large memory window may be achieved using the stoichiometric Al₂O₃ material due to efficient V{sub o} annihilation, although no complete erasure of the conductive-filament (CF) is obtained. We finally emphasize that the conduction may be described by a quantum point-contact (QPC) model down to very low current level where only a few V{sub o} defects compose the QPC constriction. The large switching variability inherent to this latter aspect is mitigated by CF shape tuning through adequate engineering of an Al₂O₃\HfO₂ bilayer.

Authors:
; ; ; ; ; ; ;  [1];  [1];  [2]; ;  [3]
  1. imec, Kapeldreef 75, B-3001 Leuven (Belgium)
  2. (Belgium)
  3. KU Leuven, Department of Physics and Astronomy, B-3001 Leuven (Belgium)
Publication Date:
OSTI Identifier:
22305770
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 13; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; BREAKDOWN; CRYSTAL DEFECTS; CURRENTS; DENSITY; ELECTRIC CONDUCTIVITY; ELECTRIC CONTACTS; FILAMENTS; HAFNIUM OXIDES; LAYERS; OXYGEN; STOICHIOMETRY; VACANCIES

Citation Formats

Goux, L., E-mail: gouxl@imec.be, Fantini, A., Nigon, R., Strangio, S., Degraeve, R., Kar, G., Chen, Y. Y., Jurczak, M., Raghavan, N., KU Leuven, Dept. Elektrotechniek ESAT-MICAS, B-3001 Leuven, De Stefano, F., and Afanas'ev, V. V. On the bipolar resistive-switching characteristics of Al₂O₃- and HfO₂-based memory cells operated in the soft-breakdown regime. United States: N. p., 2014. Web. doi:10.1063/1.4896841.
Goux, L., E-mail: gouxl@imec.be, Fantini, A., Nigon, R., Strangio, S., Degraeve, R., Kar, G., Chen, Y. Y., Jurczak, M., Raghavan, N., KU Leuven, Dept. Elektrotechniek ESAT-MICAS, B-3001 Leuven, De Stefano, F., & Afanas'ev, V. V. On the bipolar resistive-switching characteristics of Al₂O₃- and HfO₂-based memory cells operated in the soft-breakdown regime. United States. doi:10.1063/1.4896841.
Goux, L., E-mail: gouxl@imec.be, Fantini, A., Nigon, R., Strangio, S., Degraeve, R., Kar, G., Chen, Y. Y., Jurczak, M., Raghavan, N., KU Leuven, Dept. Elektrotechniek ESAT-MICAS, B-3001 Leuven, De Stefano, F., and Afanas'ev, V. V. Tue . "On the bipolar resistive-switching characteristics of Al₂O₃- and HfO₂-based memory cells operated in the soft-breakdown regime". United States. doi:10.1063/1.4896841.
@article{osti_22305770,
title = {On the bipolar resistive-switching characteristics of Al₂O₃- and HfO₂-based memory cells operated in the soft-breakdown regime},
author = {Goux, L., E-mail: gouxl@imec.be and Fantini, A. and Nigon, R. and Strangio, S. and Degraeve, R. and Kar, G. and Chen, Y. Y. and Jurczak, M. and Raghavan, N. and KU Leuven, Dept. Elektrotechniek ESAT-MICAS, B-3001 Leuven and De Stefano, F. and Afanas'ev, V. V.},
abstractNote = {In this article, we investigate extensively the bipolar-switching properties of Al₂O₃- and HfO₂-based resistive-switching memory cells operated at low current down to <1 μA. We show that the switching characteristics differ considerably from those typically reported for larger current range (>15 μA), which we relate as intrinsic to soft-breakdown (SBD) regime. We evidence a larger impact of the used switching-oxide in this current range, due to lower density of oxygen-vacancy (V{sub o}) defects in the SBD regime. In this respect, deep resetting and large memory window may be achieved using the stoichiometric Al₂O₃ material due to efficient V{sub o} annihilation, although no complete erasure of the conductive-filament (CF) is obtained. We finally emphasize that the conduction may be described by a quantum point-contact (QPC) model down to very low current level where only a few V{sub o} defects compose the QPC constriction. The large switching variability inherent to this latter aspect is mitigated by CF shape tuning through adequate engineering of an Al₂O₃\HfO₂ bilayer.},
doi = {10.1063/1.4896841},
journal = {Journal of Applied Physics},
number = 13,
volume = 116,
place = {United States},
year = {Tue Oct 07 00:00:00 EDT 2014},
month = {Tue Oct 07 00:00:00 EDT 2014}
}
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