Non-volatile magnetic random-access memories (MRAMs), such as spin-transfer torque MRAM and next-generation spin–orbit torque MRAM, are emerging as key to enabling low-power technologies, which are expected to spread over large markets from embedded memories to the Internet of Things. Concurrently, the development and performances of devices based on two-dimensional van der Waals heterostructures bring ultracompact multilayer compounds with unprecedented material-engineering capabilities. Here we provide an overview of the current developments and challenges in regard to MRAM, and then outline the opportunities that can arise by incorporating two-dimensional material technologies. We highlight the fundamental properties of atomically smooth interfaces, the reduced material intermixing, the crystal symmetries and the proximity effects as the key drivers for possible disruptive improvements for MRAM at advanced technology nodes.
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M.C., S.C., B.D., A.F., K.G., M.-B. M., P.S., S.O.V. and S.R. acknowledge the European Union Horizon 2020 research and innovation programme for grant number 881603 (Graphene Flagship). The Catalan Institute of Nanoscience and Nanotechnology is supported by the Severo Ochoa Centres of Excellence programme, funded by the Spanish Research Agency (AEI, grant number SEV-2017-0706). S.O.V. thanks the European Research Council (ERC) under grant agreements 306652 SPINBOUND and 899896 SOTMEM, and the Spanish Research Agency (AEI), Ministry of Science and Innovation (PID2019-111773RB-I00/AEI/10.13039/501100011033). H.Y. is supported by SpOT-LITE programme (A*STAR grant, A18A6b0057) through RIE2020 funds, Singapore Ministry of Education (MOE) Tier 2 (R-263-000-E29-112), National Research Foundation (NRF) Singapore Investigatorship (NRFI06-2020-0015) and Samsung Electronics’ University R&D programme. S.C. and G.S.K. acknowledge IMEC’s Industrial Affiliation Program on MRAM devices. M.C. and M.J. acknowledge the French National Research Agency through the MAGICVALLEY project (ANR-18-CE24-0007). B. Dieny acknowledges ERC MAGICAL 669204. M.C. acknowledges H. X. Yang, A. Hallal and F. Ibrahim. P.S. and B. Dlubak acknowledge the French National Research Agency through the SoGraphMem project (ANR-18-CE24-0007).
The authors declare no competing interests.
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Yang, H., Valenzuela, S.O., Chshiev, M. et al. Two-dimensional materials prospects for non-volatile spintronic memories. Nature 606, 663–673 (2022). https://doi.org/10.1038/s41586-022-04768-0