Stochastic modeling of mushroom-waveguide photodetectors

摘要

Waveguide photodetectors (WGPDs) are one of the promising candidates to solve the tradeoff between the quantum efficiency and the transit time in the surface illuminated pho-todiodes where the lightwave is incident laterally perpendicular to the direction of the flow of generated carriers, enhancing both high speed and quantum efficiency. In Mushroom-WGPDs, the performance degradation due its parasitic capacitance and the load resistance is overcome due to the mesa mushroom structure. Inaccuracies in the dimensions of'Mushroom-WGPDs due to the fabrication affect its functionality and its operating bandwidth. In this work, a stochastic analysis of the Mushroom-WGPD that is based on Drift Diffusion model and Monte Carlo simulations is presented. The tolerances of the dimensions of the Mushroom-WGPD and their impacts on the photodetector performance and bandwidth-biasing are studied for different biasing. Both the standard deviations and the probability distribution function of bandwidth are studied.