The Effect of MOS Transistor Body Connection on Sub-THz Fundamental Oscillator Performance Above 200 GHz in 65-nm CMOS

In this paper, the effect of MOS transistor body connection in fundamental signal sources at sub-THz frequencies is analyzed with three different body connections. It is shown that the body connection of the MOS transistor is one of the critical factors for designing efficient fundamental sources in the sub-THz range using CMOS technology. Floating-body type connection show better performance compared to ground-connected body, and direct body-source connections. The design is simulated with an accurate EM solver with a post-layout parasitic-extracted schematic including all the interconnects. Simulations show a 1.57-V peak-to-peak differential output swing with the optimized floating-body approach; while, ground-connected body, and direct body-source connections resulted with 1.26-V and 1.23- V respectively. Oscillator consumes only 11 mW power from a 1-V supply with floating-body approach.