Performance analysis of Vertical Photodetector for Efficient on Chip Optical Interconnect

In this work, the optical absorption analysis of the Vertical Photodetector for Optical Interconnect is done. For efficient detection of the signal at the receiver, a photodetector is required for designing of efficient optical interconnects. The light transmitted from the optical source is coupled into the waveguide and received by the detector. Vertical photodetector can be designed using Si and Ge but due to large bandgap, Si can't detect the optical signal efficiently at wavelengths used for optical communication (1.3 to 1.55 mu m). This can be done by using smaller band gap material (Ge) to design a photo-detector. Ge photo-detector offer high performance optical interface solutions. The Optical absorption property of photodetector is analyzed using Lumerical FDTD. It is observed that the absorption rate of vertical Ge-Si photodetector vary in different plane and provides high responsivity at 1.55 mu m because the region of absorption can be made longer to enable full absorption. We investigate the absorption rate of the designed vertical photodetector because the responsivity of the photodetector depends on the absorption rate. The designed structure can be used in on-chip optical interconnect with high absorption rate and low cost.