OEIC technologies for high-speed optical interconnection system

Abstract

As the level of integration and the power of computation increase, methods of interconnecting computational elements attract more attention and the total system performance is bottlenecked by the problems associated with electrical interconnections. Optical interconnections have advantages of practically unlimited bandwidth and absence of crosstalk. To utilize such merits of optical interconnections, a large number of low-cost high-performance optoelectronic integrated circuits (OEICs) are needed. This paper focuses on monolithically integrated receiver OEICs that consist of InP/InGaAs p-i-n photodiodes and fully ion-implanted InP junction field-effect transistors (JFETs). In the formation of shallow InP p-n junctions we use a co-implantation technique in which we implant a group V element together with Be, a dopant, and take advantage of damage and stoichiometry effects. We fabricate a p-i-n/JFET amplifier receiver front-end circuit and a receiver 2×2 crosspoint switch circuit using this technique. We also develop bandwidth enhancement designs using inductive peaking and cascoding. Finally, we demonstrate a single-channel, free-space optical interconnection system with a bandwidth of 1.5 GHz and an interconnection length of 50 cm.