A W-Band Low Loss, High Power SPDT Switch Using Reverse Saturated $0.13\ \mu \mathrm{m}$ SiGe HBTs

This paper presents a sigle-pole double-throw (SPDT) switch using a $0.13\ {\mu} \mathbf{m}$ reverse saturated SiGe HBTs. The switch is based on ${\lambda}/4$ transmission line and the performance of insertion loss and isolation is improved by adding a small area of substrate contacts around the NPN transistors and an isolation-boosting inductance between the collector and emitter, respectively. A measured insertion loss of 1.4-1.6 dB is achieved at 81-98 GHz and < 2.5 dB in the whole W-band frequencies. The measured output port-to-port isolation is > 25 dB at 78-97 GHz and > 20dB in W-band frequencies. The return loss is better than 10 dB at 75-102 GHz. To the best of the authors' knowledge, the proposed switch demonstrates the lowest insertion loss in the silicon-based SPDT switches in W-band frequencies.