Gate-All-Around Transistors at 3nm: Device Physics, Fabrication Challenges, and Beyond FinFET Scaling
DOI:
https://doi.org/10.58445/rars.3111Keywords:
Gate-All-Around Transistors (GAAFETs), Nanosheet Field-Effect Transistors (NSFETs), 3nm Semiconductor Technology, Fabrication Challenges in Advanced Nodes, Complementary FETs (CFETs), 2D Materials for CMOS Scaling, Semiconductors, AI Hardware, VLSI DesignAbstract
This paper provides a comprehensive review of Gate-All-Around (GAA) transistors at the 3nm technology node, a critical inflection point in the semiconductor industry. While Moore's Law, as an empirical observation of exponential transistor scaling, faces fundamental physical and economic limits, the industry continues to advance through architectural innovation. The report first traces the evolution from planar to three-dimensional (3D) FinFETs, highlighting how the latter's scaling limitations at sub-5nm dimensions necessitated a new paradigm. It then delves into the superior device physics of GAA transistors, which achieve enhanced electrostatic control by fully wrapping the channel, thereby mitigating severe short-channel effects and quantum phenomena that degrade FinFET performance. A detailed analysis of the engineering challenges including advanced EUV lithography, complex inner spacer fabrication, and nanosheet stacking variability, is presented. The paper also provides a comparative review of the divergent strategies of leading foundries: Samsung's early, high-risk transition to GAAFETs at 3nm versus TSMC's decision to push its refined FinFET architecture to its absolute limit. Finally, it explores the roadmap beyond 3nm, examining emerging architectures like Complementary FETs (CFETs), the potential of novel two-dimensional (2D) materials as a replacement for silicon, and the profound influence of artificial intelligence (AI) and machine learning (ML) workloads in driving system-level, rather than purely transistor-level, innovation.
References
ASML. (2022). What is a gate-all-around transistor? ASML. https://www.asml.com/en/news/stories/2022/what-is-a-gate-all-around-transistor
Anonymous. (2023). Introduction of gate-all-around FET (GAAFET). ResearchGate. https://www.researchgate.net/publication/376672940_Introduction_of_Gate-All-Around_FET_GAAFET
Intel. (2023). Moore’s Law. Intel Newsroom. https://newsroom.intel.com/press-kit/moores-law
IMEC. (2023). Is Moore’s Law dead? IMEC. https://www.imec-int.com/en/semiconductor-education-and-workforce-development/microchips/moores-law/moores-law-dead
Anonymous. (2020). The effect of fin structure in 5 nm FinFET technology. ResearchGate. https://www.researchgate.net/publication/338338449_The_Effect_of_Fin_Structure_in_5_nm_FinFET_Technology
JoMM. (2019). The effect of fin structure in 5 nm FinFET technology. Journal of Microelectronic Manufacturing. http://www.jommpublish.org/static/publish/FD/A5/3C/FD22E94A56A6F248835F13A5A9/10.33079.jomm.19020405.pdf
MDPI. (2023). A comparative study of the effects of different doping profiles on the performance of junctionless cylindrical surrounding gate MOSFETs with ultrascaled dimensions. Micromachines, 15(4), 424. https://www.mdpi.com/2072-666X/15/4/424
Cronfa Swansea. (2020). Benchmarking of FinFET, nanosheet, and nanowire FET architectures for future technology nodes. Swansea University. https://cronfa.swan.ac.uk/Record/cronfa53939/Download/53939__17053__639075c9775a4e0098bed8791269586c.pdf
Anysilicon. (2023). The ultimate guide to gate-all-around (GAA). AnySilicon. https://anysilicon.com/the-ultimate-guide-to-gate-all-around-gaa/
Google Patents. (2021). Inner spacer feature with porous dielectric material (US20210083091A1). https://patents.google.com/patent/US20210083091A1/en
Anonymous. (2020). Hybrid dual-κ spacer strategy to optimize parasitic capacitance and driving performance in GAA nanosheet FETs. ResearchGate. https://www.researchgate.net/figure/Spacer-morphology-and-inner-spacer-process-challenges-a-conventional-spacer-b-inner_fig2_340841753
Samsung. (2022). Samsung begins chip production using 3nm process technology with GAA architecture. Samsung Newsroom. https://news.samsung.com/global/samsung-begins-chip-production-using-3nm-process-technology-with-gaa-architecture
Samsung. (2024). Foundry process technology. Samsung Semiconductor. https://semiconductor.samsung.com/foundry/process-technology/logic-node/
Semiconductor Digest. (2018, May). EUV lithography: Extending the patterning roadmap to 3nm. Semiconductor Digest. https://sst.semiconductor-digest.com/2018/05/ultra-violet-lithography-extending-the-patterning-roadmap-to-3nm/
Anonymous. (2024). Simulation of vertically stacked 2-D nanosheet FETs. ResearchGate. https://www.researchgate.net/publication/388786072_Simulation_of_Vertically_Stacked_2-D_Nanosheet_FETs
MDPI. (2022). A detailed comparison of channel width folding for FinFET, vertically stacked nanosheet and nanowire transistors. Nanomaterials, 12(10), 1739. https://www.mdpi.com/2079-4991/12/10/1739
PatentPC. (2024). 5nm vs. 3nm chips: Performance gains and market adoption rates. PatentPC. https://patentpc.com/blog/5nm-vs-3nm-chips-performance-gains-and-market-adoption-rates-latest-data
Samsung. (2022). Samsung begins chip production using 3nm process technology with GAA architecture. Samsung Newsroom. https://news.samsung.com/global/samsung-begins-chip-production-using-3nm-process-technology-with-gaa-architecture
SemiWiki. (2023). Intel 18A node explained: How RibbonFET boosts AI scalability. SemiWiki. https://semiwiki.com/forum/threads/intel-18a-node-explained-how-ribbonfet-boosts-ai-scalability.21352/
GameGPU. (2024). Intel reveals all tech details 18A — its flagship 1.8 nm class process technology. GameGPU. https://en.gamegpu.com/iron/intel-reveals-all-tech-details-18a-power-via-ribbonfet-and-30-graphics
USPTO. (2019). 8T-SRAM cell scaling beyond 10 nm technology. U.S. Patent and Trademark Office. https://ptacts.uspto.gov/.
SemiEngineering. (2025). SRAM with mixed signal logic with noise immunity in 3nm nanosheet (IBM). SemiEngineering. https://semiengineering.com/sram-with-mixed-signal-logic-with-noise-immunity-in-3nm-nanosheet-ibm/
PatentPC. (2024). Samsung vs. TSMC vs. Intel: Who’s winning the foundry market. PatentPC. https://patentpc.com/blog/samsung-vs-tsmc-vs-intel-whos-winning-the-foundry-market-latest-numbers
TSMC. (2025). 3nm technology. TSMC. https://www.tsmc.com/english/dedicatedFoundry/technology/logic/l_3nm
Cadence. (2022). IEDM: TSMC N3 details. Cadence Breakfast Bytes Blog. https://community.cadence.com/cadence_blogs_8/b/breakfast-bytes/posts/iedm-tsmc-n3-details
SemiWiki. (2023). Samsung 3nm process technology wiki. SemiWiki. https://semiwiki.com/wikis/industry-wikis/samsung-3nm-process-technology-wiki/
Intel. (2025). Intel 18A process technology simply explained. Intel Newsroom. https://newsroom.intel.com/intel-foundry/intel-18a-process-technology-simply-explained
Electropages. (2024). Intel 18A: The future of semiconductor technology with RibbonFET and PowerVia. Electropages. https://www.electropages.com/blog/2024/10/intel-18a-future-semiconductor-technology-ribbonfet-and-powervia
Semiconductor Digest. (2024). The shape of tomorrow’s semiconductor technology. Semiconductor Digest. https://www.semiconductor-digest.com/the-shape-of-tomorrows-semiconductor-technology/
Atomfair. (2024). The post-FinFET era: Exploring the design and scaling of Gate-All-Around (GAA) nanosheet transistors. Atomfair. https://atomfair.com/scibase2/article.php?id=40
Future Timeline. (2025). First wafer-scale fabrication of 2D indium selenide semiconductors. Future Timeline. https://www.futuretimeline.net/blog/2025/08/6-first-wafer-scale-fabrication-2d-indium-selenide-semiconductors.htm
Prescouter. (2024). Roadmap to integrating 2D materials for next-gen electronics. Prescouter. https://www.prescouter.com/2024/07/roadmap-to-integrating-2d-materials/
ArXiv. (2025). A comprehensive analysis and comparison of the wafer-scale engine and Nvidia’s GPU architecture for AI acceleration. arXiv. https://arxiv.org/html/2503.11698v1
Anonymous. (2024). Exploring the synergy of AI and ML in very large scale integration design and manufacturing. ResearchGate. https://www.researchgate.net/publication/386302071_Exploring_the_synergy_AI_and_ML_in_very_large_scale_integration_design_and_manufacturing
MIT CSAIL. (2024). The death of Moore’s Law: What it means and what might fill the gap going forward. MIT CSAIL. https://cap.csail.mit.edu/death-moores-law-what-it-means-and-what-might-fill-gap-going-forward
Anonymous. (2021). Comparison of FinFET, GAA nanowire, and nanosheet FET architectures for sub-10 nm nodes. ResearchGate. https://www.researchgate.net/figure/Comparison-of-a-FinFET-b-vertically-stacked-nanosheet-GAA-FET-and-c-vertically_fig1_360743373
Chinese Journal of Semiconductors. (2008). Analysis and TCAD simulation of a gate-all-around cylindrical FinFET. Chinese Journal of Semiconductors. https://www.jos.ac.cn/fileBDTXB/oldPDF/08070503.pdf
Anonymous. (2018). Gate-all-around silicon nanowire field-effect transistors for ultimate CMOS scaling. ResearchGate. https://www.researchgate.net/figure/TCAD-simulation-results-of-a-the-carriers-density-and-b-electric-field-profiles-for_fig10_326815579
MDPI. (2023). SnO nanosheet transistor with remarkably high hole effective mobility. Nanomaterials, 15(9), 640. https://www.mdpi.com/2079-4991/15/9/640
Anonymous. (2021). Review on fabrication and simulation of nano-sheet transistors. ResearchGate. https://www.researchgate.net/figure/Schematic-diagrams-for-NSFET-fabrication-47_fig3_351590703
Anonymous. (2018). FinFET versus gate-all-around nanowire FET: Performance scaling and variability. ResearchGate. https://www.researchgate.net/publication/323090508_FinFET_versus_Gate-All-Around_Nanowire_FET_Performance_Scaling_and_Variability
SPIE. (2024). A survey of structural design and performance impacts of GAA MBCFET. Proceedings of SPIE, 13547, 1354729. https://www.spiedigitallibrary.org/conference-proceedings-of-spie/13547/1354729
Anonymous. (2018). FinFET versus gate-all-around nanowire FET: Performance scaling and variability. ResearchGate. https://www.researchgate.net/publication/323090508_FinFET_versus_Gate-All-Around_Nanowire_FET_Performance_Scaling_and_Variability
Anonymous. (2011). Short-channel effects in double-gate FinFETs. ResearchGate. https://www.researchgate.net/figure/Short-Channel-Effects-variation-with-L-T-fin-ratio_fig1_50848469
ArXiv. (2020). Negative capacitance enables FinFET scaling beyond 3nm node. arXiv. https://arxiv.org/pdf/2007.14448
TechInsights. (2022). TSMC reveals 3nm process details. TechInsights. https://www.techinsights.com/blog/tsmc-reveals-3nm-process-details
Patsnap. (2024). Integrating GAA-based logic gates for computation in ELMs. Patsnap. https://eureka.patsnap.com/report-integrating-gaa-based-logic-gates-for-computation-in-elms
Anonymous. (2019). 3nm GAA technology featuring multi-bridge-channel FET for low power and high performance applications. ResearchGate. https://www.researchgate.net/publication/330589929_3nm_GAA_Technology_featuring_Multi-Bridge-Channel_FET_for_Low_Power_and_High_Performance_Applications
IEDM. (2023). EUV driven GAA scaling. IEEE IEDM. https://www.mapyourshow.com/mys_shared/iedm23/handouts/2-3_Mon_16241.pdf
WikiChip. (2022). TSMC N3 and challenges ahead. WikiChip Fuse. https://fuse.wikichip.org/news/7375/tsmc-n3-and-challenges-ahead/
TechInsights. (2022). TSMC reveals 3nm process details. TechInsights. https://www.techinsights.com/blog/tsmc-reveals-3nm-process-details
SemiWiki. (2022). IEDM 2022: TSMC 3nm. SemiWiki. https://semiwiki.com/semiconductor-manufacturers/tsmc/322688-iedm-2022-tsmc-3nm/
VKTR. (2024). The end of Moore’s Law? AI chipmakers say it’s already happened. VKTR. https://www.vktr.com/ai-technology/the-end-of-moores-law-ai-chipmakers-say-its-already-happened/
Asterisk Magazine. (2024). The transistor cliff. Asterisk Magazine. https://asteriskmag.com/issues/03/the-transistor-cliff
GM Insights. (2024). Gate-all-around (GAA) transistor market size, share, trends & forecast. GM Insights. https://www.gminsights.com/industry-analysis/gate-all-around-gaa-transistor-market
Future Timeline. (2025). First wafer-scale fabrication of 2D indium selenide semiconductors. Future Timeline. https://www.futuretimeline.net/blog/2025/08/6-first-wafer-scale-fabrication-2d-indium-selenide-semiconductors.htm
MDPI. (2023). A breakthrough in the batch production of wafer-scale monolayer MoS₂ by chemical vapor deposition. Crystals, 13(8), 1275. https://www.mdpi.com/2073-4352/13/8/1275
NCBI. (2022). Wafer-scale synthesis of 2D MoS₂ for next-generation integrated electronics. Nature Communications, 13(1), 435. https://pmc.ncbi.nlm.nih.gov/articles/PMC9419721/
Downloads
Posted
Categories
License
Copyright (c) 2025 Aditya Sinha, Nishant Choudhary

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.