A D-Band to J-Band Low-Noise Amplifier with High Gain-Bandwidth Product in an Advanced 130 nm SiGe BiCMOS Technology

In this work, a broadband low noise amplifier fabricated in an advanced 130 nm SiGe BiCMOS technology with of 470/650 GHz is presented. The amplifier comprises 5 pseudo-differential cascode stages. Double-peak transformer-based matching stages in the first 3 stages are used to achieve high gain and low noise across a large bandwidth. A suitable set of baluns was developed to facilitate on-wafer measurements from 100 GHz to 325 GHz. The amplifier provides a peak small-signal gain of 34.6 dB at 160 GHz and 235 GHz. The 3 dB bandwidth is 131 GHz - 277 GHz. The measured noise figure is between 8.4 dB to 12 dB, including baluns. With the balun losses de-embedded, the amplifier's peak small-signal gain increases to 37 dB and stays above 30 dB from 117 GHz to 285 GHz, while the lowest noise figure is 7.1 dB at 155 GHz. The achieved stays in between 0 dBm - 1 dBm from 150 GHz to 265 GHz. The amplifier consumes 152 mW with a Vcc of 3 V.

I. Introduction

High gain and large bandwidth (BW) are key features for many applications in the millimeter-wave (mmW) and (sub-) terahertz (THz) frequency range, including the upcoming 6G communications [1], radar systems [2], or radiometry [3]. Offering high fabrication yield, low cost, and a good integration level in combination with of up to 505/720 GHz [4], silicon technologies are well suitable for RF front-end circuits. Low-noise amplifiers (LNAs) are the most critical receiver part that impacts the systems' Signal-to-Noise ratio (SNR) and bandwidth. Especially for radiometry, LNAs have to provide the challenging combination of high gain and low noise figure (NF) across a large bandwidth to allow minimum noise-equivalent temperature differences (NETD) for real-time passive imaging [3].