SnS2-BN/SnSe Tri layer Heterojunctions for High Responsivity and Low Dark Current Self-Powered Near violet Detector

Near-violet (NV) detectors based on two-dimensional materials have attracted much attention due to their atomic-scale thickness and various band gaps. Among them, tin disulfide (SnS ₂ ) has demonstrated significant potential for high-performance NV detectors due to its unique photoelectric properties. However, SnS ₂ -based NV detector still have drawbacks such as low responsivity and high dark current. In this work a tri-layer van der Waals heterojunction of tin disulfide/h-boron nitride/tin selenide (SnS ₂ /h-BN/SnSe) is proposed. The detector based on such tri-layer heterojunction exhibits an excellent self-powered detection performance to 405-nm NV illumination with a responsivity of 1.5 AW ^-1 , a low dark current of 2.6 pA, and a high fill factor of 51.8%, superior to detectors based on SnS ₂ /SnSe bi-layer heterojunctions and most other two-dimensional materials. This study provides an efficient optimizing strategy for SnS ₂ -based self-powered detector, thereby offering an opportunity for implementing innovation in NV detectors.