RESEARCH TRENDS AND FUTURE-DIRECTIONS IN ULTRA-HIGH-SPEED COMPOUND SEMICONDUCTOR IC TECHNOLOGY

The most prominent feature of compound semiconductor integrated circui ts (ICs) is their ultra-high-speed performance, The development of 10- Gbit/s ICs has almost been finished and the next stage aiming at 40 Gb it/s or more has been taken off. Such ultra-high-speed ICs require new types of interconnection and circuit design as well as improved trans istor performance, For transistors, MESFETs, which have already been w idely used, are making steady progress toward higher speed, intensive research is being performed on both GaAs-based and InP-based HFETs and HBTs, Transistor performance is pushing 200 GHz and ICs with speeds o ver 40 Gbit/s have been demonstrated, Three-dimensional interconnectio n with low loss and low interference has been proposed, A distributed configuration is becoming more important as a design technique.