Very-broadband-IC-module design technology

High-speed, very broadband ICs for large capacity optical transmission systems have established a significant niche in the compound semiconductor market. We have already developed 10Gbit/s-class IC families, and now research and development into 40Gbit/s-class ICs or higher has begun. In the design of these broadband circuits for operating at microwave and millimeter-wave frequencies, the problem of coping with distributed circuit effects is probably the most crucial subject. This paper demonstrates new design technologies, which include a circuit technique that allows distributed circuit configurations to be employed extensively and a packaging and module design technique that utilizes electromagnetic field simulations. Baseband amplifier modules and analog multiplier circuits that demonstrate the highest performance ever reported have been designed and fabricated based on the new techniques.