Photoconductive and Photovoltaic Properties of Dual-Junction Thin-Film-Based Er-Doped ZnO/MoS/P-Si Heterostructure

This work features the photoconductive and photovoltaic phenomenon of fabricated heterostructure erbium (Er)-doped zinc oxide (ZnO)/molybdenum disulfide (MoS2)/P-silicon (P-Si). The proposed structure shows good performance in terms of detection range, covering ultraviolet (UV) to near-infrared (NIR) region with a peak responsivity of 9.08 A/W, a detectivity of $4.8\times 10^{{13}}$ Jones at −1 V, and a self-detection of 0.08 A/W at 0 V. This outstanding photodetection in reverse bias is due to the efficient carrier separation facilitated by MoS2/P-Si and Er-ZnO/MoS2 interface. The device also exhibits solar cell-like properties with open-circuit voltage ( ${V}~_{\text {OC}}$ ), short-circuit current density ( ${J} _{\text {SC}}$ ), and power conversion efficiency (PCE) of 0.170 V, $3.41\times 10^{-{2}}$ mA/cm2, and 1.2%, respectively. This solar cell-like performance is due to the built-in voltage created at the MoS2/P-Si junction.