Abstract
Dynamic Random Access Memory (DRAM), a critical component in modern computing systems, relies heavily on the structural integrity of its active area (AA) - a fin-shaped transistor region responsible for charge transfer in memory cells. During advanced DRAM fabrication, the plasma etching process often induces shape distortions in the AA region (termed “wiggling AA”), which degrade capacitive charging/discharging efficiency and device reliability. While this phenomenon is widely observed in industry, its mechanistic origins remain poorly understood, necessitating systematic investigation to enable precision etching control. In this paper, we fabricated active area transistors of DRAM structures and characterized the etching results using three-dimensional (3D) reconstruction based on focused ion beam-scanning electron microscopy (FIB-SEM) data. In parallel, we developed a 3D etching feature profile model that correlates process parameters with structural deformation and simulated the etching process under three oxygen flow rates. By integrating experimental data and simulation results, we systematically analyzed the mechanistic origins of the wiggling AA effect and demonstrated improvement by modulating the oxygen flow rate. This study bridges the gap between empirical observations and fundamental etching mechanisms, offering actionable strategies for optimizing high-density DRAM manufacturing processes.
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All data needed to evaluate the conclusions are present in the paper. Additional data and raw data are available upon request from the corresponding author.
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Acknowledgements
Supported by the National Key R&D Program of China (No. 2023YFB4402600), the National Natural Science Foundation of China (No. 62474194), the International Partnership Program of the Chinese Academy of Sciences (No.102GJHZ2024059GC and 102GJHZ2024029FN). Supported by the Austrian Federal Ministry of Labour and Economy, the National Foundation for Research, Technology and Development, and the Christian Doppler Research Association, Austria.
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Ziyi Hu: Conceptualization; Formal analysis; Investigation; Methodology; Project administration; Software; Validation; Visualization; Writing—original draft; Writing—review and editing. Jing Wen: Investigation; Methodology; Writing—original draft. Chaoran Yang: Investigation; Methodology. Hua Shao: Investigation; Validation. Yuxuan Zhai: Investigation; Validation. Rui Ge: Investigation; Validation. Xiaobin He: Investigation. Zongzheng Men: Investigation; Methodology. Yi Yang: Investigation; Methodology. Dianming Sun: Investigation; Methodology. Zhongming Liu: Investigation; Methodology. Dashan Shang: Writing—original draft; Writing—review and editing. Zhiqiang Li: Validation. Junjie Li: Conceptualization; Validation; Writing—original draft. Lado Filipovic: Funding acquisition; Validation; Writing—review and editing. Rui Chen: Funding acquisition; Investigation; Project administration; Resources; Supervision; Writing—original draft; Writing—review and editing. Ling Li: Funding acquisition; Project administration.
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Communications Engineering thanks Du Zhang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editors: [Philip Coatsworth]. A peer review file is available.
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Hu, Z., Wen, J., Yang, C. et al. 3D reconstruction and etching profile simulation for wiggling active area effect in dynamic random access memory manufacturing. Commun Eng (2026). https://doi.org/10.1038/s44172-026-00626-3
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DOI: https://doi.org/10.1038/s44172-026-00626-3
