A Broadband 300 GHz Power Amplifier in a 130 nm SiGe BiCMOS Technology for Communication Applications

A broadband three-stage pseudo-differential SiGe-interconnection bipolar transistor (HBT) power amplifier (PA) for high-speed communication at around 300 GHz is presented. The amplifier is fabricated in an experimental 130-nm SiGe BiCMOS technology with an $f_{t}/f_{\max }$ of 470/650 GHz. The use of asymmetric coupled line transformers is proposed to facilitate broadband impedance transformation with device reactance compensation at all amplifier interfaces. The amplifier achieves a maximum small-signal power gain of 23.0 dB and a $P_{\mathrm{ sat}}/{\mathrm{ OP}}_{\mathrm{ 1\,dB}}$ up to 9.7/6.7 dBm, respectively. It shows a 3-dB bandwidth of 63 GHz (239–302 GHz) in small-signal operation and 94 GHz (223–317 GHz) when saturated. The amplifier consumes about 360 mW at a 3-V supply voltage yielding a peak power-added efficiency (PAE) of 1.95% at 260 GHz.