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arXiv · 0911.3116

Utilization of a Buffered Dielectric to Achieve High Field-Effect Carrier Mobility in Graphene Transistors

Damon B. Farmer·Hsin-Ying Chiu·Yu-Ming Lin·Keith A. Jenkins·Fengnian Xia·Phaedon Avouris
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Abstract

We utilize an organic polymer buffer layer between graphene and conventional gate dielectrics in top-gated graphene transistors. Unlike other insulators, this dielectric stack does not significantly degrade carrier mobility, allowing for high field-effect mobilities to be retained in top-gate operation. This is demonstrated in both two-point and four-point analysis, and in the high-frequency operation of a graphene transistor. Temperature dependence of the carrier mobility suggests that phonons are the dominant scatterers in these devices.

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Damon B. Farmer, Hsin-Ying Chiu, Yu-Ming Lin, Keith A. Jenkins, Fengnian Xia, Phaedon Avouris. 2009-11-16. Utilization of a Buffered Dielectric to Achieve High Field-Effect Carrier Mobility in Graphene Transistors. https://doi.org/10.1021/nl902788u

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