A 10-Gbit/s laser driver IC with i-AlGaAs/n-GaAs doped-channel hetero-MISFETs (DMTs)

Ultra-high-speed laser driver ICs for multigigabit per second optical communication systems have been demonstrated using gate recess structure doped-channel hetero-MISFETs (DMTs) with 0.35- mu m-length gates. The laser driver ICs were fabricated with advanced processes, such as direct-writing electron-beam lithography and air-bridge interconnects. They have operated at 10 Gb/s with risetimes and falltimes as fast as 40 ps, which is the highest speed ever reported. The laser driver ICs can drive up to 60 mA into a 25- Omega load. In addition, direct laser diode modulation has been realized at 10-Gb/s.<>