Optimal Design and Noise Analysis of High-Performance DBR-Integrated Lateral Germanium (Ge) Photodetectors for SWIR Applications

This work presents the high-performance Si/SiO2 distributed Bragg reflector (DBR)-integrated lateral germanium (Ge) p-i-n photodetectors (PDs) for atmospheric gas sensing and fiber-optic telecommunication networks in short-wave infrared (SWIR) regime. In addition, this study also proposes an optoelectronic compact small-signal noise equivalent circuit model (SSNECM) of designed device to compute performance at detectors’ output. Various figure-of merits including current under dark illumination, responsivity, detectivity, bandwidth, proposed are estimated room temperature (RT) incident optical power 0.5 μW. Furthermore, impact width height scaling on current, bandwidth investigated optimize device. The validation is done by comparing various parameters detectivity with other Ge PDs. results show reduced trade-off between responsivity At λ=1550 nm, achieves a high SNR >2×1011Jones 120 dB (at 3 THz), respectively, bias voltage -2V. These encouraging pave path future development low-noise high-speed detectors.