A SiGe HBT $D$ -Band LNA With Butterworth Response and Noise Reduction Technique

This letter presents a wideband high-gain fourstage cascode D-band low noise amplifier (LNA) implemented in a 0.13-μm SiGe BiCMOS technology. A shunt inductor that is used at the intermediate node of the cascode topology to reduce the noise contribution of the common base transistor is analyzed and employed for the first time for the SiGe HBT technology. Furthermore, the staggered-tuning technique based on the Butterworth distribution is utilized to have a wideband flat-gain characteristic. The designed LNA has a measured 32.6-dB peak gain at 144.5 GHz with a 3-dB bandwidth of 52 GHz. The measured noise figure (NF) is lower than 6.1 dB across the whole D-band, and its minimum value is 4.8 dB. The total dc power consumption is 28 mW. To the authors' best knowledge, these results demonstrate the lowest NF performance and the widest 3-dB bandwidth among the Dband LNAs implemented in the silicon-based technologies. The effective chip area excluding the pads is 0.6 mm
²
, and the total IC occupies an area of 1 mm
²
.