InP based long wavelength optoelectronic integrated circuits (OEICs) have recently drawn attention because they promise the low cost, high performance, and high reliability required for the deployment of fiber communication systems.1 An OEIC transmitter suitable for advanced system applications must meet some stringent performance requirements. The laser has to operate at a single wavelength with a side-mode suppression ratio of ~35 dB to assure low-mode partition noise and low chirping. The threshold current should be very low (≈10 mA) to reduce power dissipation. The bandwidth should be wide enough for multigigabit direct modulation. The electronic device should possess a high cutoff frequency, good driving capability, and robust and reliable Schottky contact. The requirement for the electronic device is particularly difficult for InP based material because a simple MESFET or MISFET structure does not perform satisfactorily, and a more advanced device structure such as an InGaAs/InAlAs MODFET requires precise control in epitaxial growth and processing. Therefore, the great challenge imposed on InP based OEIC technology is to integrate the state-of-the-art lasers and transistors together with little performance trade-off.
© 1990 Optical Society of AmericaPDF Article