Graphene Transistors and Photodetectors

Single layer graphene transistors demonstrate low I ON /I OFF ratio at room temperature. While they show promising results when applied for high-speed analog circuits in the gigahertz range, their implementation for logic devices is not favorable. Opening the band gap by means of quantum confinement improves the I ON /I OFF dramatically, but at the cost of decrease of device channel mobility. Therefore, graphene based FET research will be concentrated around the band-gap opening in bilayer graphene (BLG) by means of vertical electric fields. Although there are several challenging points in the realization of BLG-FET, it has a chance to demonstrate high enough I ON /I OFF ratio at a moderate carrier mobility. It is reasonable to assume that future graphene device research will also keep a strong focus on the tunneling or variable-barrier configuration structures.