TITLE:
Millimeter Wave Ring Oscillator Using Carbon Nano-Tube Field Effect Transistor in 150 GHz and Beyond
AUTHORS:
Davood Fathi, Baback Beig Mohammadi
KEYWORDS:
CNTFET; CNT Interconnect; Millimeter Wave; Ring Oscillator
JOURNAL NAME:
Circuits and Systems,
Vol.4 No.2,
April
17,
2013
ABSTRACT: Carbon Nano-Tube Field Effect Transistors (CNTFETS) are the competitor of the conventional MOSFET technology due to their higher current drive capability, ballistic transport, lesser power delay product, higher thermal stability, and so on. Based on these promising properties of CNTFETs, a CNTFET-based millimeter wave ring oscillator operating around 150 GHz and beyond is introduced here in 32 nm technology node. To prevent overestimation, the CNT interconnects between transistors are also included in simulation, which are assumed to be a single layer of ballistic metallic CNTs in parallel. For the sake of simplicity in RF design, the oscillator is based on CNTFET-based inverters. The inverters with DC gain of 87.5 dB are achieved by proper design with the non-loaded delay around 0.6 ps, which is at least one order of magnitude better than the same 32 nm MOSFET-based inverters. The oscillator’s average power consumption is as low as 40 μW with the fundamental harmonic amplitude of around –6.5 dB. These values are, based on our knowledge, for the first time reported in the literature in CNTFET-based oscillator designs. Also, on the average, the performance of the designed oscillator is 5 - 6 times better than MOSFET-based designs.