Vertical Barrier Heterostructures for Reliable, Robust, and High‐Performance Ultraviolet Detection

Abstract Photodetectors based on low‐dimensional materials usually suffer from serious optical power‐dependent photoresponse and low reliability, particularly in the ultraviolet regime. The barrier photodetector is an effective and reliable strategy where the barrier layer can block the low‐energy charge carriers while allowing for a flow of the high‐energy photocarriers. Here, vertical barrier heterostructure photodetectors (VBHPs), consisting of a graphene bottom electrode, a MoS₂ light absorber, and an h‐BN energy barrier, for reliable, robust, and high‐performance ultraviolet detection are reported. The asymmetric barrier distribution in the conduction/valence band at the MoS₂/h‐BN interface results in an ultralow noise current of 1.69 × 10^‐15 A Hz^‐1/2 at room temperature, stable photo on/off states exceeding 10⁴ cycles at 300 K and 400 K, a light power‐independent high responsivity of 416.2 mA W^‐1 at 360 nm, a high photo on–off ratio of 1.2 × 10⁵ at 360 nm, high measured detectivities (3.2 × 10¹⁰ Jones at 266 nm and 9.9 × 10¹⁰ Jones at 360 nm), and wide linear dynamic ranges. The VBHPs show a high potential for new‐type reliable ultraviolet detection.