Abstract
Electronic switches based on the migration of high-density point defects, or memristors, are poised to revolutionize post-digital electronics. Despite significant research, key mechanisms for filament formation and oxygen transport remain unresolved, hindering our ability to predict and design device properties. For example, experiments have achieved 10 orders of magnitude longer retention times than predicted by current models. Here, using electrical measurements, scanning probe microscopy, and first-principles calculations on tantalum oxide memristors, we reveal that the formation and stability of conductive filaments crucially depend on the thermodynamic stability of the amorphous oxygen-rich and oxygen-poor compounds, which undergo composition phase separation. Including the previously neglected effects of this amorphous phase separation reconciles unexplained discrepancies in retention and enables predictive design of key performance indicators such as retention stability. This result emphasizes non-ideal thermodynamic interactions as key design criteria in post-digital devices with defect densities substantially exceeding those of today's covalent semiconductors.
| Original language | English |
|---|---|
| Pages (from-to) | 3970-3993 |
| Number of pages | 24 |
| Journal | Matter |
| Volume | 7 |
| Issue number | 11 |
| DOIs | |
| State | Published - Nov 6 2024 |
Funding
The work by J.L. B.R. D.S. and Y.L. at the University of Michigan was supported by the National Science Foundation (NSF) under grant ECCS-2106225 and startup funding from the University of Michigan College of Engineering. Y.L. acknowledges support from an Intel Rising Star Gift. W.D.L. and S.Y. were supported by the NSF under grant CCF-1900675. The computational work by A.A. and W.S. was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under award DE-SC0021130. This research also used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under contract DE-AC02-05CH11231 using NERSC award BES-ERCAP0020148. The authors also acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing HPC resources that have contributed to the research results reported within this paper. The work at Sandia National Laboratories was supported by the Laboratory-Directed Research and Development (LDRD) program. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc. for the DOE's National Nuclear Security Administration under contract DE-NA-0003525. A.A.T. P.M. O.P. and A.V.I. were partly supported by the DOE Office of Science Research Program for Microelectronics Codesign (sponsored by ASCR, BES, HEP, NP, and FES) through the Abisko Project, PM Robinson Pino (ASCR). S.K. was supported by the Energy Frontier Research Center (EFRC) Reconfigurable Electronic Materials Inspired by Nonlinear Neuron Dynamics (reMIND) sponsored by the DOE Office of Science. This paper describes objective technical results and analyses. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the DOE or the United States Government. The work at the University at Albany was supported by the Air Force Research Laboratory under agreements FA8750-21-1-1018 and FA8750-21-1-1019. The US Government may reproduce and distribute reprints for Governmental purposes, despite any copyright notation. The views and conclusions expressed herein are solely those of the authors and do not necessarily reflect the official policies or endorsements of the Air Force Research Laboratory or the US Government. The authors acknowledge the Michigan Center for Materials Characterization for use of the instruments and staff assistance. Fabrication of the RRAM devices was conducted at the University of Michigan Lurie Nanofabrication Facility. A part of the ToF-SIMS measurements was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility, and using instrumentation within ORNL's Materials Characterization Core provided by UT-Battelle, LLC under contract DE-AC05-00OR22725 with the DOE. Finally, we thank Christoph Baeumer (University of Twente), Elliot J. Fuller (Sandia National Labs), and Ilia Valov and Stephan Menzel (Forschungszentrum J\u00FClich) for helpful discussions and feedback. J.L. and Y.L. conceived the experiment and analyzed the experimental data. J.L. measured RRAM device performance, prepared all materials characterization samples for the TaOX samples, and conducted the X-ray measurements. D.S. prepared the HfOX samples. J.L. and S.Y. fabricated RRAM devices. J.L. and B.R. performed the phase-field simulations. A.A. and W.S. conducted the DFT and entropy calculations. S.L.P. R.H. and A.A.T. performed the AES measurements. J.L. T.C. O.P. and P.M. performed conductive atomic force microscopy. E.T.H. and A.V.I. performed the ToF-SIMS measurements. K.S. performed transmission electron microscopy. Y.L. supervised the project. All authors contributed to data interpretation and writing the text. The authors declare no competing interests. The work by J.L., B.R., D.S., and Y.L. at the University of Michigan was supported by the National Science Foundation (NSF) under grant ECCS-2106225 and startup funding from the University of Michigan College of Engineering. Y.L. acknowledges support from an Intel Rising Star Gift. W.L. and S.Y. were supported by the NSF under grant CCF-1900675 . The computational work by A.A. and W.S. was supported by the US Department of Energy (DOE), Office of Science , Basic Energy Sciences (BES), under award DE-SC0021130 . This research also used resources of the National Energy Research Scientific Computing Center ( NERSC ), a DOE Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under contract DE-AC02-05CH11231 using NERSC award BES-ERCAP0020148 . The authors also acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing HPC resources that have contributed to the research results reported within this paper. The work at Sandia National Laboratories was supported by the Laboratory-Directed Research and Development ( LDRD ) program. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the DOE\u2019s National Nuclear Security Administration under contract DE-NA-0003525 . A.A.T., P.M., O.P., and A.V.I. were partly supported by the DOE Office of Science Research Program for Microelectronics Codesign (sponsored by ASCR , BES , HEP , NP , and FES ) through the Abisko Project, PM Robinson Pino ( ASCR ). This paper describes objective technical results and analyses. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the DOE or the United States Government. The work at the University at Albany was supported by the Air Force Research Laboratory under agreements FA8750-21-1-1018 and FA8750-21-1-1019 . The US Government may reproduce and distribute reprints for Governmental purposes, despite any copyright notation. The views and conclusions expressed herein are solely those of the authors and do not necessarily reflect the official policies or endorsements of the Air Force Research Laboratory or the US Government. The authors acknowledge the Michigan Center for Materials Characterization for use of the instruments and staff assistance. Fabrication of the RRAM devices was conducted at the University of Michigan Lurie Nanofabrication Facility. A part of the ToF-SIMS measurements was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility, and using instrumentation within ORNL\u2019s Materials Characterization Core provided by UT-Battelle, LLC under contract DE-AC05-00OR22725 with the DOE . Finally, we thank Christoph Baumer (University of Twente), Elliot J. Fuller (Sandia National Labs), and Ilia Valov and Stephan Menzel (Juelich Research Center) for helpful discussions and feedback.
Keywords
- amorphous
- MAP 3: Understanding
- memristor
- oxygen diffusion
- phase separation
- phase-field model
- retention