Triple-Mesa InGaAs/InP SPAD for Heterogenous Integration with InP Waveguides

We present the design of a novel triple mesa InGaAs/InP SPAD and compare it with a well-developed planar version. The mesa detector is considered as an easier path towards its heterogenous integration with InP waveguides for quantum photonic applications. Electrical and optical parameters of both the mesa and planar SPADs were investigated, at the typical temperature of 225 K for such devices. Despite the different geometries and approaches for electric field control and confinement, similar results can be obtained thanks to proper design and sizing. In particular, high photon detection efficiency (PDE) at 1550 nm wavelength was achieved (30% for the planar, 29% for the mesa), with front-side illumination.