Quasi-non-volatile capacitorless DRAM based on ultralow-leakage edge-contact MoS₂ transistors

Nature Materials (2026)Cite this article Two-dimensional semiconductors are emerging as crucial materials for the post-Moore era. However, the transition to industrial-scale applications is hindered by engineering challenges, including the contact engineering. Among different strategies, edge contact offers advantages of ultimate contact scaling and the elimination of Fermi level pinning, but struggles with co-optimization between on-state current, threshold voltage and off-state leakage current. Here we address these challenges by utilizing an in situ multistep process, in which etching, soft plasma treatment and metal deposition are performed sequentially within the same custom-designed high-vacuum chamber to minimize interface defects. This approach enables molybdenum disulfide (MoS2)-based edge-contact field-effect transistors exhibiting an ultralow leakage current of 1.75 × 10−20 A μm−1 at zero gate voltage and an enhanced on-state current. The optimized capacitorless two-transistor dynamic random-access memory (DRAM) achieves a quasi-non-volatile memory operation, 5-bit memory accuracy and nanosecond-level write speed, demonstrating the potential for two-dimensional semiconductor-based circuits and memory devices.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutAll data needed to evaluate the findings of this study are available within the Article. Source data are available from Figshare via https://doi.org/10.6084/m9.figshare.30818588 (ref. 59). Source data are provided with this paper.Jiang, J., Wu, P., Liu, Y., Kong, J. & Peng, L.-M. 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Research data supporting ‘Quasi-non-volatile capacitorless DRAM based on ultra-low leakage edge contact MoS2 transistor’. Figshare https://doi.org/10.6084/m9.figshare.30818588 (2025).Download referencesThis work was supported by the National Key Research and Development Program (grant 2021YFA1200500), the National Natural Science Foundation of China (grants 62374037, 12334005, 12174060 and 12404089), the Innovation Program of Shanghai Municipal Education Commission (grant 2021-01-07-00-07-E00077), the Science and Technology Commission of Shanghai Municipality (grant 23JC1401100) and the Shanghai Pilot Program for Basic Research—Fudan University 21TQ1400100 (grant 23TQ008). This work has been supported by the New Cornerstone Science Foundation through the XPLORER PRIZE.These authors contributed equally: Saifei Gou, Yuxuan Zhu, Zhejia Zhang, Menglin Huang, Jinshu Zhang.State Key Laboratory of Integrated Chip and Systems, School of Microelectronics, Fudan University, Shanghai, People’s Republic of ChinaSaifei Gou, Yuxuan Zhu, Zhejia Zhang, Menglin Huang, Jinshu Zhang, Xiangqi Dong, Mingrui Ao, Qicheng Sun, Zhenggang Cai, Yan Hu, Yufei Song, Jiahao Wang, Haojie Chen, Yuchen Tian, Xinliu He, Jieya Shang, Zhengjie Sun, Qihao Chen, Yang Liu, Shiyou Chen, Peng Zhou & Wenzhong BaoShenzhen Six Carbon Technology, Shenzhen, People’s Republic of ChinaZihan XuSchool of Information Science and Technology, Fudan University, Shanghai, People’s Republic of ChinaXiaofei Yue & Chunxiao CongShaoxin Laboratory, Shaoxing, People’s Republic of ChinaYin Wang, Xiaojun Tan, Peng Zhou & Wenzhong BaoFrontier Institute of Chip and System, Fudan University, Shanghai, People’s Republic of ChinaLiwei LiuSchool of Microelectronics, Shanghai University, Jiading, Shanghai, People’s Republic of ChinaMengjiao LiChangxin Memory Technologies, Hefei, People’s Republic of ChinaChen Yang, Hao Meng, Mingyuan Liu & Huihui LiShanghai AtomIC Technology, Shanghai, People’s Republic of ChinaWenzhong BaoSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarW.B., P.Z. and S.C. supervised the project. S.G., Y.Z., Z.Z. and J.Z. conceived the experiments. M.H. and S.C. performed the theoretical calculations. S.G., Y.Z., Z.Z., J.Z., X.D., M.A., Q.S., Y.H., Y.S., H.C., Y.T., X.H., J.W., Z.S., Q.C., Y.L. and J.S. fabricated the devices. S.G., Y.Z., Z.Z., Z.C. and J.Z. performed the electrical measurements. Z.X. conducted the growth of MoS2. X.Y. and C.C. performed the Raman and PL experiments. S.G., Y.Z., M.H., Z.Z. and J.Z. wrote the original article. W.B., P.Z., S.C., Y.W., L.L., X.T., M.L., C.Y., H.M., M.L. and H.L. revised the article. All authors discussed the results and commented on the manuscript.Correspondence to Shiyou Chen, Peng Zhou or Wenzhong Bao.The authors declare no competing interests.Nature Materials thanks Vita Pi-Ho Hu, Won Jong Yoo, Han Wang for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Supplementary Figs. 1–25 and Supplementary Tables 1 and 2.Statistical Source DataStatistical Source DataStatistical Source DataStatistical Source DataSpringer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsGou, S., Zhu, Y., Zhang, Z. et al. Quasi-non-volatile capacitorless DRAM based on ultralow-leakage edge-contact MoS2 transistors. Nat. Mater. (2026). https://doi.org/10.1038/s41563-025-02470-wDownload citationReceived: 26 January 2025Accepted: 15 December 2025Published: 14 January 2026Version of record: 14 January 2026DOI: https://doi.org/10.1038/s41563-025-02470-wAnyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative