Tunable Solid State and Flexible Graphene Electronics

TL;DR

This paper presents the development of tunable, flexible graphene field effect devices using a composite dielectric, achieving low operating voltages, high mobility, and stable performance under bending conditions.

Contribution

It introduces a novel composite dielectric with LiF in PMMA for graphene FEDs, enabling low-voltage operation and flexibility without mobility loss.

Findings

Reduced gate voltage from 10 V to 1 V with increased LiF concentration.

Achieved electron and hole mobilities of 350 and 310 cm2/Vs.

Maintained mobility with only 5-12% variation under bending.

Abstract

We demonstrate tunable solid state and flexible graphene field effect devices (FEDs) fabricated using a poly(methylmethacrylate) (PMMA) and lithium fluoride (LiF) composite dielectric. Increasing the concentration of LiF in the composite dielectric reduces the operating gate voltages significantly from 10 V to 1 V required leading to a decrease in resistance. Electron and hole mobility of 350 and 310 cm2/Vs at VD = -5 V are obtained for graphene FEDs with 10 % LiF concentration in the composite. Using composite dielectric also enabled excellent performance on flexible substrates without any significant change in mobility and resistance. Flexible FEDs with only 5 % and 12 % variation in mobility for 300 and 750 bending are obtained.