Vertical Van Der Waals Epitaxy of p‐Mo_xRe_1‐Xs₂ on GaN for Ultrahigh Detectivity Uv–vis–NIR Photodetector

Abstract

Abstractvan der Waals (vdW) heterogeneous integration and doping engineering have emerged as crucial factors in advancing the development of functional device systems. This work presents a fully vertical 2D/3D vdW stacking p‐MoxRe1‐xS2/GaN (x = 0.10 ± 0.02) heterojunction photodetector, integrating multiple strategies for enhanced performance, such as mixed‐dimensional stacking, p‐type doping, vertical device design, and type‐II band alignment. By integrating horizontal, vertical, and quasi‐vertical devices on a Free‐standing (FS)‐GaN substrate, the vertical p‐MoxRe1‐xS2/GaN device demonstrates superior performance, including high Ilight/Idark ratio (1.48 × 106), large Responsivity (888.69 AW−1), high specific detectivity (D*) (6.13 × 1014 Jones), and fast response speed (rise/decay time of 181 ms/259 ms). Moreover, the spectral response encompasses the ultraviolet (UV), visible, and near‐infrared (NIR) regions through energy band integration and bandgap modulation. This design surpasses previous devices, highlighting the potential of highly sensitive and micro‐integrated optoelectronic devices enabled by vertical vdW heterogeneous integration.

High Sensitive and Stable UV–Vis Photodetector Based on MoS2/MoO3 vdW Heterojunction

“…2D black phosphorus (BP) has a hole mobility of up to 1000 cm 2 V –1 s –1 and a tunable band gap, but its instability in the environment is the main reason limiting its further development. , Transition-metal dichalcogenides (TMDs) not only have the advantages of high mobility, high photosensitivity, high transparency, and adjustable band gap but also have high thermal and chemical stability, which has great application potential in the next generation of ultrathin electronic devices. − Most of the 2D semiconductor materials discovered so far are narrow band gaps, such as BP, TMDs, GaSe, GaS, and FePSe 3 , which limit the potential application of devices in UV detection. Recently, some scientists have used 2D materials and 3D wide-bandgap semiconductor materials to construct heterojunctions to improve the UV detection capability of devices, such as Mo x Re 1– x S 2 /GaN, TiO 2 /V 2 CT x , PtSe 2 /β-Ga 2 O 3 , and ZnS/MoS 2 . However, PD based on 2D wide-bandgap semiconductor materials has rarely been proposed.…”