We fabricate planar graphene field-effect transistors with self-aligned side-gate, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim tunneling in vacuum, which becomes dominant at higher voltages. We report a field-emission current density as high as 1µA/µm between graphene flakes. These findings are important for the miniaturization of atomically thin devices.
Leakage and field emission in side-gate graphene field effect transistors
IEMMO, LAURA;Luongo, Giuseppe;DI BARTOLOMEO, Antonio
Writing – Original Draft Preparation
2016-01-01
Abstract
We fabricate planar graphene field-effect transistors with self-aligned side-gate, using a single lithographic step. We demonstrate side-gating below 1V with conductance modulation of 35% and transconductance up to 0.5 mS/mm at 10 mV drain bias. We measure the planar leakage along the SiO2/vacuum gate dielectric over a wide voltage range, reporting rapidly growing current above 15 V. We unveil the microscopic mechanisms driving the leakage, as Frenkel-Poole transport through SiO2 up to the activation of Fowler-Nordheim tunneling in vacuum, which becomes dominant at higher voltages. We report a field-emission current density as high as 1µA/µm between graphene flakes. These findings are important for the miniaturization of atomically thin devices.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
