Performance Analysis of a Nanocolumn-RTD VCO for Emerging THz Wireless Applications

The data rates which can be processed by integrated communication systems are increasing as the CMOS process and photonic technologies scale. Emerging bandwidth-hungry applications demand new solutions based on terahertz (THz) systems. This work proposes a GaAs/AlAs nanocolumn-Resonant Tunneling Diode (Nano-RTD) device as a voltage-controlled oscillator (VCO) for frequency generation in the THz spectrum window, i.e., Y-band (325 - 500 GHz). A comprehensive semianalytical approach to evaluating the performance of the Nano-RTD VCO device is developed. The latter addresses the oscillation frequency, maximum oscillation frequency, tuning range, output power, DC consumption power, and DC/AC conversion efficiency. Moreover, the oscillation stability of the designed device in the Y-band was numerically verified. Results shown that the device can operate in the Y-band (@ ~500 GHz and 300 K), with a very-low DC power consumption down to 0.16 mW, along with a good DC/AC conversion efficiency (2.4%). The Nano-RTD VCO is compatible with current CMOS fabrication technology and has a very compact footprint (2000 nm²). Finally, the device may be used as part of system solutions to satisfying emerging THz wireless applications such as in-body nano-communication, wireless nano-networks, and network-on-chip.