SiGe broadband amplifiers with up to 80 GHz bandwidth for optical applications at 43 Gbit/s and beyond

Abstract

Two broadband amplifiers for 43 Gbit/s data transmission were realized in a SiGe-HBT technology with ft = 120 GHz and fmax = 100 GHz: a differential lumped limiting amplifier with 36 dB differential gain and 26 GHz bandwidth and a two stage distributed amplifier with a gain-bandwidth product of 820 GHz. Additionally, for applications beyond 43 Gbit/s, a distributed amplifier was realized in a more advanced SiGe process (ft, fmax > 200 GHz). This amplifier achieves 13 dB gain and more than 80 GHz bandwidth, which is the highest bandwidth reported so far for Si-based amplifiers.