Atomic layer deposited Al₂O₃ for gate dielectric and passivation layer of single-walled carbon nanotube transistors

High performance single-walled carbon nanotube field effect transistors (SWCNT-FETs) fabricated with thin atomic layer deposited (ALD) Al ₂O₃ as gate dielectrics and passivation layer are demonstrated. A 1.5 μm gate-length SWCNT-FETs with 15 nm thick Al ₂O₃ insulator shows a gate leakage current below 10 ^-11 A at -2.5 V < V_g < + 7 V, a subthreshold swing of S ∼ 105 mV/decade, and a maximum on current of -12 μA at a reverse gate bias of -1 V. Lack of hysteresis in IV characteristics and low low frequency noise indicate high quality oxide-nanotube interface achieved utilizing ALD Al₂O₃ as gate dielectrics and passivation layer.