Top and side gated epitaxial graphene field effect transistors

TL;DR

This paper presents and compares three types of epitaxial graphene FETs grown on silicon carbide, highlighting their electrical properties and potential for future all-graphene device structures.

Contribution

It introduces first-generation epitaxial graphene FETs on different faces of silicon carbide and explores their electrical characteristics and advantages.

Findings

Si-face FETs have off/on resistance ratios >30

C-face FETs show higher mobility up to 5000 cm2/Vs

Initial results on all-graphene side gate FETs are promising

Abstract

Three types of first generation epitaxial graphene field effect transistors (FET) are presented and their relative merits are discussed. Graphene is epitaxially grown on both the carbon and silicon faces of hexagonal silicon carbide and patterned with electron beam lithography. The channels have a Hall bar geometry to facilitate magnetoresistance measurements. FETs patterned on the Si-face exhibit off-to-on channel resistance ratios that exceed 30. C-face FETs have lower off-to-on resistance ratios, but their mobilities (up to 5000 cm2/Vs) are much larger than that for Si-face transistors. Initial investigations into all-graphene side gate FET structures are promising.