Self-aligned graphene field-effect transistors with polyethyleneimine doped source/drain access regions

Hema C. P. Movva; Michael E. Ramón; Chris M. Corbet; Sushant Sonde; Sk. Fahad Chowdhury; Gary Carpenter; Emanuel Tutuc; Sanjay K. Banerjee

doi:10.1063/1.4765658

arXiv · 1210.5535

Self-aligned graphene field-effect transistors with polyethyleneimine doped source/drain access regions

Hema C. P. Movva·Michael E. Ramón·Chris M. Corbet·Sushant Sonde·Sk. Fahad Chowdhury·Gary Carpenter·Emanuel Tutuc·Sanjay K. Banerjee

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Abstract

We report a method of fabricating self-aligned, top-gated graphene field-effect transistors (GFETs) employing polyethyleneimine spin-on-doped source/drain access regions, resulting in a 2X reduction of access resistance and a 2.5X improvement in device electrical characteristics, over undoped devices. The GFETs on Si/SiO$_2$ substrates have high carrier mobilities of up to 6,300 cm$^2$/Vs. Self-aligned spin-on-doping is applicable to GFETs on arbitrary substrates, as demonstrated by a 3X enhancement in performance for GFETs on insulating quartz substrates, which are better suited for radio frequency applications.

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Hema C. P. Movva, Michael E. Ramón, Chris M. Corbet, Sushant Sonde, Sk. Fahad Chowdhury, Gary Carpenter, Emanuel Tutuc, Sanjay K. Banerjee. 2012-10-19. Self-aligned graphene field-effect transistors with polyethyleneimine doped source/drain access regions. https://doi.org/10.1063/1.4765658

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