Fast high-efficiency integrated waveguide photodetectors using novel hybrid vertical/butt coupling geometry

We report a novel coupling geometry for integrated waveguide photodetectors−a hybrid vertical coupling/butt coupling scheme that allows the integration of fast, efficient, photodetectors with conventional double heterostructure waveguides. It can be employed to yield a planar, or pseudo-planar, surface that supports further levels of integration. The approach is demonstrated with a 25-μm-long p-i-n detector integrated with an InP/InGaAsP/InP waveguide, which displays a high (∼90%) efficiency and large (∼15 GHz) bandwidth. This is the fastest high-efficiency integrated waveguide photodetector reported to date.