InP/InGaAs HBT ICs for 40 Gbit/s optical transmission systems

An IC chip set for 40 Gbit/s TDM optical transmission systems was designed and fabricated using an InP/InGaAs HBT technology. For digital ICs, a modulator driver, a D-type flip flop at 20 Gbit/s, and a 2:1 selector at 40 Gbit/s were fabricated. Also, three analog ICs were developed: the five-section cascode distributed amplifier which obtained a gain of 9.5 dB in the frequency range of 1-50 GHz, the 41.9 dB/spl Omega/ transimpedance amplifier which achieved more than 40 GHz bandwidth assuming 50 fF input capacitance for the photodetector, the two-stage differential amplifier which obtained a 7.5 dB gain with a bandwidth of 40 GHz.