Vertical Barrier Heterostructures for Reliable, Robust, and High‐Performance Ultraviolet Detection
Yanrong Wang, Feng Wang, Shu-Hui Li, Jia Yang, Tao Yan, Yuchen Cai, Zilong Wu, Xueying Zhan, Jun He, Zhenxing Wang
Abstract
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 MoS 2 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 MoS 2 /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 10 4 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 × 10 5 at 360 nm, high measured detectivities (3.2 × 10 10 Jones at 266 nm and 9.9 × 10 10 Jones at 360 nm), and wide linear dynamic ranges. The VBHPs show a high potential for new‐type reliable ultraviolet detection.