InGaAs/InP p-i-n photodiodes integrated with AlGaAs/GaAs optical waveguides and air-bridge coplanar metal waveguides using total internal reflectors

Summary form only given. Monolithic optoelectronic integrated circuits (OEICs) are of considerable interest for future optical communications systems in the 1.3-1.6 /spl mu/m wavelength range due to the significant reduction in interconnections and ease of assembly. For some OEIC applications, it is useful to use GaAs substrates instead of InP because of the mature fabrication technology for electronic components on GaAs. For high-speed device applications, air-bridge coplanar metal waveguides are an attractive means to interconnect high-speed photodiodes, which results in a reduction of the parasitic capacitance of the diodes. Of the various waveguide photodiode integration approaches, total internal-reflection (TIR) mirror vertical coupling is regrowth-free and applicable to single and double heterostructure waveguides. In the paper, we used a thin InP buffer layer, grown by solid source molecular beam epitaxy, to suppress the dislocations between In/sub 0.53/Ga/sub 0.47/As/InP photodiode and AlGaAs/GaAs waveguide layers. The GaAs-based optical waveguide couples light to the p-i-n InGaAs photodetector by an etched, vertically deflecting TIR mirror.