Study on ZnO network-based UV detection

Abstract

ZnO network synthesized by the FTS (Flame Transport Synthesis) method is considered as one of the best materials for UV detection with high exciton binding energy ~60 meV and wide band gap energy ~3.37 eV. This study is focused on temperature varied UV response analysis for illuminated wavelength lies in UV-B region 365nm with optical power as 5.64 μW. The result obtained indicates that the maximum UV response ~39 comes is at the 75°C for 365 nm UV light. The determined response/recovery time for 365nm at 75°C is 1.35 s/5.35 s respectively, which shows efficient response/recovery rate for UV light. Thus, this study exhibits 75 °C temperature as optimal temperature. Maximum response at 365nm is ascribed as due to its correspondence to the band gap energy of ZnO and 75°C is the optimal temperature for efficient band bending and oxygen density gradient which leads to the quick response-recovery of oxygen ions from the ZnO sensing surface.