Graphene tunnel field effect transistor

Electric Field Sensing in Graphene Device

Electric field sensing has various real-life applications such as the early prediction of lightning.We have effectively used graphene as an electric field sensor that can detect both positive and negative electric fields, where the response of the sensor is recorded as the change in drain current in the presence of the electric field. The mechanism of sensing relies on the transfer of electrons between graphene and the traps at the SiO2/graphene interface. This changes the carrier concentration in the graphene channel, which is reflected as the change in drain current. The direction of electron transfer depends on the polarity of the electric field. Under a positive electric field the electrons are transferred into graphene from the traps, while for a negative electric field, the electrons are transferred from graphene to the traps.

(Left figure) Emission of electrons from the trap to graphene under a positive electric field
(Right figure) Transfer of electrons from graphene to the interface trap under a negative electric field