A novel equivalent circuit model for waveguide-separated absorption charge multiplication-avalanche photodetector (WG-SACM-APD)

Waveguide photodetectors are promising high-speed photodetectors compared to conventional photodetectors because of solving the problem of bandwidth efficiency tradeoff. The equivalent circuit model of detectors can be utilized to confirm the device performance prior to fabrication. In this paper a novel equivalent circuit model for waveguide-separated absorption charge multiplication avalanche photodetector (WG-SACM-APD) is presented. Using basic circuit components and considering the theory of linear time invariant system frequency domain modeling of this detector including parasitic sources are achieved. Finally the transfer function and detector's bandwidth with respect to the multiplication gain are also investigated and there are good agreements with experimental results.