The Lateral Photovoltaic Effect of WSeS/Si Heterojunction

Abstract

Two-dimensional transition metal dichalcogenides (2D TMDs) have garnered considerable interest for next-generation photodetectors, owing to their remarkable electrical and optoelectronic characteristics. This work systematically investigates the lateral photovoltaic characteristics of the WSeS/Si heterojunction. X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy confirm that the WSeS thin film prepared via pulsed laser deposition (PLD) possesses excellent crystalline quality. At room temperature, the WSeS/n-Si (84 mV/mm) and WSeS/p-Si (106 mV/mm) heterojunctions exhibit strong position sensitivity under 532-nm illumination, with relaxation times of 0.22 and 0.41 μs, respectively. Furthermore, the laser response characteristics of lateral photovoltaic effect under high-intensity illumination can effectively avoid the failure of two-dimensional material optoelectronic devices under high-intensity light. These results confirm the significant potential of the WSeS/Si heterojunction photodetector for self-powered position-sensitive detection.