Design and Performance Evaluation of a Low-Power Highly Sensitive Double-Gate Junctionless FET UV Photodetector

This paper presents a double-gate junctionless field effect transistor (DGJLFET) based ultraviolet (UV) photodetector for highly sensitive low-power applications. In the proposed device, two gate electrodes sandwich the channel, increasing the significant current flow and mitigating the short-channel effects. Each gate has a length of 45 nm and an oxide layer thickness of 1.5 nm. For effective absorption of UV light, a thin film of Zinc Oxide is utilized as the gate material. Performance metrics, such as sensitivity, responsivity, and detectivity, are compared with a conventional double-gate metal oxide semiconductor field effect transistor (DGMOSFET). The proposed DGJLFET UV photodetector achieves a sensitivity of$1.47 \times 10^{\wedge} 10$, responsivity of$4.30 \times 10^{\wedge} 8 \mathrm{A}/\mathrm{W}$, and Ion/Ioffof$\sim 10^{\wedge} 10$under a very low UV light intensity of$140 \mu W/\text{cm}^{\wedge} 2$. Overall, the results demonstrate that the DGJLFET-based UV photodetector offers superior performance compared to the DGMOSFET-based UV photodetector at a 350 nm wavelength of incident light.