High Bandwidth-Efficiency Product MPIN Photodiode With Parallel-Connected Microstructure

摘要

A novel Microstructure PIN photodiode (MPIN-PD) using the ray-optic theory of light trapping effect is presented and analyzed numerically. The MPIN-PD is proposed from an ordinary large-diameter PIN-PD by introducing an obconical shape surrounded by a V-groove trench. The photon-material interaction is increased by using the microstructure in the PIN-PD. It can control light and cause syntony in the absorption layer, reducing the junction capacitance of the PD, and suppressing the tradeoff between the efficiency and bandwidth. Thus, both 3-dB bandwidth and quantum efficiency can be improved simultaneously. The parameters of the MPIN-PD, including the depth and apex angles of the micro-structure, the distance between the cone and V-groove trench are carefully studied to estimate their positive effects of the performance of the MPIN-PD. The transmission line model is exploited for the specific structure to design the electrodes’ distribution.