Distributed Circuits in SiGe BiCMOS for Next-generation Fiber-optic Communications

In this thesis, various distributed circuits topologies in SiGe BiCMOS are investigated as a means to overcome the strict requirements of next-generation optical communications. A low-noise DC-135GHz bandwidth distributed amplifier was designed and fabricated in 55nm SiGe BiCMOS for ultra-wideband receiver applications. In the same technology, a novel large-swing, time-interleaved power DAC test circuit was implemented as a proof-of-concept to investigate the maximum achievable bandwidth with a differential output swing of 6 Vpp, as needed to directly drive an optical modulator. Additionally, key blocks of a large-swing frequency-interleaved transmitter architecture were designed and fabricated in a 90nm SiGe BiCMOS technology. These included a 125GHz bandwidth PIN-diode SPST switch with record linearity, a novel vertically-coupled 40-100 GHz band-pass filter, and a large-swing driver with 80GHz bandwidth.M.A.S