Performance of p -PEDOT:PSS/ n -SnO2 hybrid UV photodetector annealed at high temperature

Post-deposition annealing temperature plays an important role in the performance of many photodetectors. In this study, we investigated the effect of annealing on the ultraviolet (UV) detection properties of a visible-blind p-poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/n-SnO2 heterojunction device after exposure to various temperatures ranging from 60 to 210 °C. Our results indicate that the signal-to-noise ratio, responsivity, external quantum efficiency, and specific detectivity of the device initially increase with annealing temperature up to 150 °C and thereafter decrease with further increase in temperature. At −6.0 V reversed bias, the device exposed to 150 °C produce the optimum responsivity of 90.02 ± 1.68 mA W−1, quantum efficiency of (30.58 ± 0.57)%, and detectivity of (3.09 ± 0.19) × 108 Jones. Furthermore, the optimized device at −6.0 V exhibited a rapid rise time of 97.45 ms and a fall time of 98.81 ms. The study highlights the improvement in UV sensing performance of the p-PEDOT:PSS/n-SnO2 heterojunction device on annealing at 150 °C.