A 0.54 THz signal generator in 40 nm bulk CMOS with 22 GHz tuning range

This work presents a 540 GHz signal generator consisting of a LC-VCO with buffer, implemented in a 40 nm bulk CMOS technology. The buffer is optimized for non-linear operation, to maximize the third harmonic generation at 540 GHz. The third harmonic is coupled to the load by a transformer. To accurately measure the output power, a WR-1.5 probe has been used. The output power is -31 dBm at 543 GHz, for 16.8 mW of DC power consumption. The output frequency can be tuned from 561.5 GHz to 539.6 GHz, resulting in a 21.9 GHz tuning range,the highest reported so far for CMOS THz oscillators. The 3-dB output bandwidth is 5.5 GHz.