Microwave characterization of graphene field effect transistors on lithium niobate ferroelectric substrates

In this paper we discuss our recent microwave measurements on a graphene transistor fabricated on lithium niobate (LiNbO3) substrates. Top gated graphene field-effect transistors (G-FETs) were fabricated on LiNbO3 substrates and their high frequency operation were analyzed. The measured cutoff frequency fT as a function of gate voltage derived from S parameters is found to be proportional to the G-FET's transconductance. An intrinsic cut off frequency up to 10 GHz was measured for a 600 nm gate graphene transistor.