Low-dark-current waveguide InGaAs metal-semiconductor-metal photodetector monolithically integrated with InP grating coupler on III-V CMOS photonics platform

摘要

The fabrication of waveguide InGaAs metal-semiconductor-metal (MSM) photodetector (PD) monolithically integrated with an InP grating coupler has been demonstrated using the III-V CMOS photonics platform. The grating coupler shows approximately 28% coupling efficiency, which allows wafer-scale testing with better coupling and alignment tolerance than edge-fire coupling. The InGaAs PD with an InP/InAlAs Schottky barrier enhancement (SBE) layer exhibits a low dark current of 0.75 nA at 1 V bias. When the bias is 4 V, a responsivity of approximately 0.19 A/W with 3 nA dark current is achieved. The fabricated PD on a III-V-on-insulator wafer can be used for the fabrication of low-power receiver chips for optical interconnects. (C) 2016 The Japan Society of Applied Physics