Single-walled carbon nanotube mixers

We report fabrication and experimental characterization of metallic single-walled carbon nanotube (SWNT) mixers. Metallic nanotubes attached to gate dielectric (SiO2) and suspended nanotubes were fabricated over Poly-Si gate structures. Devices were characterized for their RF mixing performance up to 80MHz. Under identical input signals, the suspended nanotube mixers had about 8 to 13dB higher convergence gain than the devices attached to the gate dielectric. The advantages of using patterned Poly-Si gate for RF mixers are low parasitic capacitance from the pad to SWNT contacts, and compatibility of Poly-Si gate material with subsequent high temperature growth of SWNTs.