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Designing crystallization in phase-change materials for universal memory and neuro-inspired computing

Nature Reviews Materials volume 4, pages 150–168 (2019)Cite this article

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Abstract

The global demand for data storage and processing has increased exponentially in recent decades. To respond to this demand, research efforts have been devoted to the development of non-volatile memory and neuro-inspired computing technologies. Chalcogenide phase-change materials (PCMs) are leading candidates for such applications, and they have become technologically mature with recently released competitive products. In this Review, we focus on the mechanisms of the crystallization dynamics of PCMs by discussing structural and kinetic experiments, as well as ab initio atomistic modelling and materials design. Based on the knowledge at the atomistic level, we depict routes to improve the parameters of phase-change devices for universal memory. Moreover, we discuss the role of crystallization in enabling neuro-inspired computing using PCMs. Finally, we present an outlook for future opportunities of PCMs, including all-photonic memories and processors, flexible displays with nanopixel resolution and nanoscale switches and controllers.

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Fig. 1: Current and emerging computing units.
Fig. 2: Prototypical phase-change materials.
Fig. 3: Nucleation rate by materials design.
Fig. 4: Crystal growth from atomistic simulations.
Fig. 5: Temperature-dependent dynamics of phase-change materials.
Fig. 6: The performance of phase-change devices.
Fig. 7: Phase-change neuro-inspired computing.

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Acknowledgements

The authors acknowledge Y.-X. Zhou and J.-J. Wang for their help with figure preparations and R. Feng for useful discussions. W.Z. thanks the support of the National Natural Science Foundation of China (61774123 and 51621063), 111 Project 2.0 (BP2018008), the Youth Thousand Talents Program of China, the Young Talent Support Plan, Xi’an Jiaotong University and the International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies. R.M. and M.W. acknowledge funding from Deutsche Forschungsgemeinschaft within SFB 917 ‘Nanoswitches’. E.M. is supported at Johns Hopkins University by the US Department of Energy, Office of Basic Energy Sciences, Department of Materials Sciences and Engineering (DOE-BES-DMSE) under grant DE-FG02-13ER46056.

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Authors and Affiliations

  1. Center for Advancing Materials Performance from the Nanoscale, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an, China

    Wei Zhang

  2. Institute for Theoretical Solid-State Physics, JARA-FIT and JARA-HPC, RWTH Aachen University, Aachen, Germany

    Riccardo Mazzarello

  3. Institute of Physics IA, JARA-FIT and JARA-HPC, RWTH Aachen University, Aachen, Germany

    Matthias Wuttig

  4. Peter Grünberg Institute PGI-10, Forschungszentrum Jülich GmbH, Jülich, Germany

    Matthias Wuttig

  5. Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD, USA

    Evan Ma

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W.Z. researched the data and wrote the manuscript. R.M., M.W. and E.M. edited the manuscript. All authors made a substantial contribution to the discussion of content.

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Zhang, W., Mazzarello, R., Wuttig, M. et al. Designing crystallization in phase-change materials for universal memory and neuro-inspired computing. Nat Rev Mater 4, 150–168 (2019). https://doi.org/10.1038/s41578-018-0076-x

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