Energy distribution of channel electrons and its impacts on the gate leakage current in graphene field-effect transistors

The linear energy-momentum relation results in more high-energy electrons in 2D (two-dimensional) graphene FETs (field-effect transistor) than those in silicon FETs that features parabolic energy-momentum relation if the same surface electron density has been assumed in all FETs. The numerical calculations demonstrate that, under such assumption, the gate leakage currents in graphene FETs are much larger than that in silicon FETs. The results illustrate that if the conduction band offset between graphene and gate oxide is lower than 3.55 eV, the gate leakage currents in graphene electronics are more significant than those in the silicon electronics.