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  • Letter
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Length scaling of carbon nanotube transistors

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Abstract

Carbon nanotube field-effect transistors are strong candidates in replacing or supplementing silicon technology. Although theoretical studies have projected that nanotube transistors will perform well at nanoscale device dimensions1,2,3,4, most experimental studies have been carried out on devices that are about ten times larger than current silicon transistors5,6,7. Here, we show that nanotube transistors maintain their performance as their channel length is scaled from 3 µm to 15 nm, with an absence of so-called short-channel effects. The 15-nm device has the shortest channel length and highest room-temperature conductance (0.7G0) and transconductance (40 µS) of any nanotube transistor reported to date. We also show the first experimental evidence that nanotube device performance depends significantly on contact length, in contrast to some previous reports8,9,10. Data for both channel and contact length scaling were gathered by constructing multiple devices on a single carbon nanotube. Finally, we demonstrate the performance of a nanotube transistor with channel and contact lengths of 20 nm, an on-current of 10 µA, an on/off current ratio of 1 × 105, and peak transconductance of 20 µS. These results provide an experimental forecast for carbon nanotube device performance at dimensions suitable for future transistor technology nodes.

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Figure 1: Effects of channel length scaling on nanotube transistor performance.
Figure 2: Scaling to the ballistic transport regime.
Figure 3: Effects of contact length scaling on nanotube transistor performance.
Figure 4: 2Rc versus Lc trend and the complete scaling picture.
Figure 5: Extremely scaled nanotube transistor.

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Change history

  • 26 November 2010

    In the version of this Letter originally published online, the y-axis of Figure 2b should have read 'Id (μA)'. This error has now been corrected in all versions of the Letter.

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Acknowledgements

The authors thank J. Bucchignano and D. Farmer for their expert technical assistance with electron-beam lithography and atomic-layer deposition, respectively. The authors also thank A. Bol for help with carbon nanotube growth and J. Chang for assistance with the semi-automated probe station.

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A.D.F. conceived, designed and performed the experiments. A.D.F. and Z.C. analysed the data and interpreted the results. A.D.F. wrote the paper, with comments by Z.C.

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Correspondence to Aaron D. Franklin.

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The authors declare no competing financial interests.

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Franklin, A., Chen, Z. Length scaling of carbon nanotube transistors. Nature Nanotech 5, 858–862 (2010). https://doi.org/10.1038/nnano.2010.220

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