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arXiv · 1104.1599

Room-Temperature High On/Off Ratio in Suspended Graphene Nanoribbon Field Effect Transistors

Ming-Wei Lin·Cheng Ling·Yiyang Zhang·Hyeun Joong Yoon·Mark Ming-Cheng Cheng·Luis A. Agapito·Nicholas Kioussis·Noppi Widjaja·Zhixian Zhou
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Abstract

We have fabricated suspended few layer (1-3 layers) graphene nanoribbon field effect transistors from unzipped multiwall carbon nanotubes. Electrical transport measurements show that current-annealing effectively removes the impurities on the suspended graphene nanoribbons, uncovering the intrinsic ambipolar transfer characteristic of graphene. Further increasing the annealing current creates a narrow constriction in the ribbon, leading to the formation of a large band-gap and subsequent high on/off ratio (which can exceed 104). Such fabricated devices are thermally and mechanically stable: repeated thermal cycling has little effect on their electrical properties. This work shows for the first time that ambipolar field effect characteristics and high on/off ratios at room temperature can be achieved in relatively wide graphene nanoribbon (15 nm ~50 nm) by controlled current annealing.

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Ming-Wei Lin, Cheng Ling, Yiyang Zhang, Hyeun Joong Yoon, Mark Ming-Cheng Cheng, Luis A. Agapito, Nicholas Kioussis, Noppi Widjaja, Zhixian Zhou. 2011-04-08. Room-Temperature High On/Off Ratio in Suspended Graphene Nanoribbon Field Effect Transistors. https://doi.org/10.1088/0957-4484%2F22%2F26%2F265201

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