A 7-dB 43-GHz CMOS Distributed Amplifier on High-Resistivity SOI Substrates

This paper presents designs and measurements of distributed amplifiers (DAs) processed on a 130-nm silicon-on-insulator CMOS technology on either standard-resistivity (${{\hbox{10}} \ \Omega \cdot {\hbox {cm}}}$) or high-resistivity $({>}{\hbox{1 k}}\Omega \cdot {\hbox {cm}}$ ) substrates, and with either body-contacted (BC) or floating-body (FB) MOSFETs. Investigations have been carried out to assess the impact of active device performance and transmission line losses on circuit design by means of simulations, analytical calculations, and comparisons of the small-signal equivalent-circuit parameters. On standard-resistivity substrates, DAs with FB devices and lossy microstrip lines on thin film exhibit a measured gain of 7.1 dB and a unity-gain bandwidth (UGB) of 27 GHz for a dc power consumption of 57 mW. With the introduction of high-resistivity substrates, other DAs, with the same architecture and using lower loss coplanar waveguide lines, show a UGB of 51 GHz with FB devices and 47 GHz with BC devices. To the authors' knowledge, the designs presented in this paper achieve the best tradeoffs in terms of gain, bandwidth, and power consumption for CMOS-based circuits with comparable architecture.