InP-based HEMT technologies toward 100 Gbit/s ICs

This paper describes HEMT IC technology developed at NTT for 50 Gbit/s ICs, which are the key components in 40 Gbit/s optical communications systems these days. We have successfully integrated state-of-the-art HEMTs and achieved stable operation of D-FFs at over 50 Gbit/s with high yield and uniformity. It also discusses the potential of the technology for achieving 100 Gbit/s-class ICs and clarifies the HEMT performance requirements. The target performance of HEMTs is a g/sub m/ of over 1.4 S/mm with an f/sub T/ of over 280 GHz. Scaling down of HEMTs and reducing their parasitic capacitance are the major issues in achieving 100 Gbit/s operations.