3D Lumerical simulation of silicon photodiodes with microholes for high-speed short-reach intra-datacenter interconnects.

3D simulations are conducted using Lumerical software to study the performance of surface illuminated silicon positive-intrinsic-negative photodiodes with microholes. Drift-diffusion equations are solved including the effects of carrier lifetime due to Shockley-Read-Hall and Auger recombination mechanisms, as well as high field mobility. Lumerical's FDTD tool is used to determine the light absorption in the device. The generation profile is imported to Lumerical's CHARGE tool to determine the transient-limited impulse response. An equivalent circuit of the photodiode with microholes is developed for the simulation of an end-to-end high-speed system. Simulation results show an open eye diagram at 50 Gbps for 20µm×20µm devices.