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arXiv · 1112.5751

Graphene Thickness-Graded Transistors with Reduced Low-Frequency 1/f Noise

Guanxiong Liu·Sergey Rumyantsev·Michael Shur·Alexander A. Balandin
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Abstract

We demonstrate graphene thickness-graded transistors with high electron mobility and low 1/f noise (f is a frequency). The device channel is implemented with few-layer graphene with the thickness varied from a single layer in the middle to few-layers at the source and drain contacts. It was found that such devices have electron mobility comparable to the reference single-layer graphene devices while producing lower noise levels. The metal doping of graphene and difference in the electron density of states between the single-layer and few-layer graphene cause the observed noise reduction. The results shed light on the noise origin in graphene.

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Guanxiong Liu, Sergey Rumyantsev, Michael Shur, Alexander A. Balandin. 2011-12-24. Graphene Thickness-Graded Transistors with Reduced Low-Frequency 1/f Noise. https://doi.org/10.1063/1.3676277

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