Carbon nanotube field-effect transistors (CNFETs) are a promising nanotechnology for the development of energy-efficient computing. Despite rapid progress, CNFETs have only been fabricated in academic or research laboratories. A critical challenge in transferring this technology to commercial manufacturing facilities is developing a suitable method for depositing nanotubes uniformly over industry-standard large-area substrates. Such a deposition method needs to be manufacturable, compatible with today’s silicon-based technologies, and provide a path to achieving systems with energy efficiency benefits over silicon. Here, we show that a deposition technique in which the substrate is submerged within a nanotube solution can address these challenges and can allow CNFETs to be fabricated within industrial facilities. By elucidating the mechanisms driving nanotube deposition, we develop process modifications to standard solution-based methods that significantly improve throughput, accelerating the deposition process by more than 1,100 times, while simultaneously reducing cost. This allows us to fabricate CNFETs in a commercial silicon manufacturing facility and high-volume semiconductor foundry. We demonstrate uniform and reproducible CNFET fabrication across industry-standard 200 mm wafers, employing the same equipment currently being used to fabricate silicon product wafers.
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The data that support the findings of this study are available from the corresponding author upon reasonable request.
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We acknowledge support from Analog Devices Inc. (ADI), SkyWater Technology, the Defense Advanced Research Projects Agency (DARPA) Three-Dimensional System-on-Chip (3DSoC) programme (HR0011-18-3-0006) and the Air Force Research Laboratory for support. We thank S. Feindt and A. Olney from ADI and B. Ferguson from SkyWater for collaboration. We acknowledge J. Daley (MIT) for his guidance concerning helium ion microscopy, as well as the Microsystems Technology Laboratories (MTL, MIT). The views, opinions and/or findings expressed are those of the author and should not be interpreted as representing the official views or policies of the Department of Defense or the US Government.
The authors declare no competing interests.
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Bishop, M.D., Hills, G., Srimani, T. et al. Fabrication of carbon nanotube field-effect transistors in commercial silicon manufacturing facilities. Nat Electron 3, 492–501 (2020). https://doi.org/10.1038/s41928-020-0419-7
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