A 15.7-dBm 164–270 GHz Power Amplifier with Asymmetric Slotline-Based Series-Parallel Combiner in 130-nm SiGe BiCMOS Technology

This article presents a high-power wideband sub-terahertz power amplifier (PA) in a 130-nm SiGe BiCMOS technology. An asymmetric slotline-based series-parallel combiner (ASSPC) is proposed to enhance the output power and bandwidth. The ASSPC enables low-loss and wideband combining of four differential power cells while facilitating load-pull matching with reduced impedance imbalance between differential transistors. With an aid of the ASSPC, the PA achieves the highest saturated output power (P
sat
) of 15.7 dBm at 235 GHz and the widest P
sat
3-dB bandwidth of 106 GHz among the existing Si-based PAs operating above 200 GHz. It shows a peak gain of 21.2 dB and a wide 5-dB bandwidth of 78 GHz.