An Ultraviolet‐Infrared Dual‐Color Photodetector Based on GaN/MoS 2 /BP Van Der Waals Heterojunction

ABSTRACT Dual color detection technology spanning from the ultraviolet (UV) to near‐infrared (NIR) regions enables the acquisition of characteristic spectral information across multiple wavebands, which is critical for imaging, autonomous driving, and object recognition. However, the widespread adoption of such photodetectors remains challenges constrained by the heteroepitaxy difficulty of different semiconductors, low detection performance especially in IR band, and severe signal crosstalk. Therefore, achieving high performance low crosstalk UV‐NIR dual color detection in a single device has become an urgent priority. Here, we demonstrate a novel UV‐NIR dual color photodetector based on a p‐GaN/MoS 2 /BP van der Waals heterojunction, featuring a vertically stacked back‐to‐back diode configuration. The back illumination structure design significantly reduces optical crosstalk. This dual color photodetector achieves a responsivity of 125 mA W −1 and a specific detectivity of 1.8 × 10 11 Jones under 365 nm illumination at 0 V bias, while delivering a responsivity of 160 mA W −1 and a detectivity of 5.1 × 10 13 Jones under 1550 nm illumination at 0 V bias. Leveraging its unique spectral response characteristics, selective UV‐IR dual color imaging has been successfully realized. Our work paves the way to develop high performance low crosstalk dual color photodetectors through the van der Waals integration of different dimensional materials.