A behavior mode for simulating single-photon avalanche diodes is presented. The model is developed using Verilog-A
description language. The derived model is able to describe the static, the dynamic behavior, the triggering, the
self-sustaining and the self-quenching processes, and it also correctly characterizes the reverse current-voltage curve.
Simulation results confirmed the validity of the proposed model.
In this paper, a new UV and blue-extended photodiode with an octagon-ring-shaped structure is proposed, which have
increased responsivity for the UV and blue light, high responsive speed with short rise and fall time and UV/blue
selectivity. TCAD simulation approach is used to analyze the structural characteristics and photoelectric characteristics
of this new photodiode. For the structural characteristics, doping profile, potential distribution and Electric field
distribution are analyzed simply. For the photoelectric characteristics, the influences caused by doping concentration of
n-well on dark current, avalanche breakdown voltage and transient response are discussed in detail. The finger distance
(D) between two adjacent P+ anodes, the width (W) of P+ anode and the ratio of D/W are analyzed, witch affects the
spectral response, DC characteristic and transient response obviously. The work of TCAD simulation in this paper is
conducive to extract model parameters and process parameters of this new photodiode, which will further be used for
numerical simulation to analyze its photoelectric characteristics, noise characteristics more accurately. This work is also
a significant and helpful guide for device design and chip fabrication.