High-power <i>p-i-n</i> photodiode for the 1300–1550  nm spectral range with 0.5  A/W sensitivity at 50  mW optical power

Subject of study. This study investigates a p - i - n photodiode designed for the 1300–1550 nm spectral range, featuring a 150 µm entrance window diameter for receiving high-power optical signals. Aim of study. The aim is to optimize the photodiode design to enhance sensitivity under high optical radiation power within the 1300–1550 nm range. Method. Static characteristics were measured using an MPI TS150 probe station and a Keithley 2611B source measure unit. A numerical model was developed by solving a system of differential equations via finite element and volume methods using the COMSOL Multiphysics software package. Main results. The static characteristics were analyzed, and a numerical model was constructed, incorporating thermal distributions from laser radiation absorption. An optimized planar heterostructure design was proposed, showing enhanced sensitivity at high input powers. The proposed design achieves a sensitivity of 1.02 A/W–0.50 A/W over a 1–50 mW input power range, with a dark current below 15 nA at a reverse bias voltage of −3V. Practical significance. The optimized p - i - n photodiode design offers enhanced sensitivity at high optical powers, supporting greater dynamic range and efficiency in high-power optical signal transmission for fiber-optic communication systems.