TiNbO2-Based Photodetectors With Low Dark Current and High UV-to-Visible Rejection Ratio

We reported on metal-semiconductor-metal ultraviolet (UV) photodetector (PD) based on pulse-laser-deposited TiNbO
₂
alloy film. The TiNbO
₂
PD exhibited a low dark current density of ~0.46 nA/cm
²
, a high UV-to-visible rejection ratio of ~10
⁶
, and a high responsivity of ~0.22 A/W under the illumination of 310-nm light (~1.86 mW/cm
²
). Interestingly, the TiNbO
₂
alloy PD presents a blue-shift cutoff wavelength of 350 nm due to quantum size effect and alloy characteristics, which would be promising for the further research in the UV detection.