A 350-GHz Fundamental-Mode Common-Base Cross-Coupled Oscillator in 130-nm InP HBT Technology

A 350-GHz fundamental-mode oscillator with a common-base cross-coupled topology has been developed based on a 130-nm InP HBT technology. A fabricated oscillator with a typical performance showed an oscillation frequency of 344 GHz. The measured output power was 1.1 dBm with a DC power dissipation of 74.8 mW, leading to a DC-to-RF efficiency of 1.72 %. It was confirmed from the measurement that a base inductance of 4 pH (for a device size of 5-$\mu$m emitter length) needs to be included for accurate prediction of the circuit performance, which would serve a useful guideline for circuit designs with the given process technology.