A high-performance photodetector with the structure of NiO/SiO2/ZnO nanowires has been proposed. The devices with 6-nm-thick SiO2 exhibited a better rectification ratio ( Jforward/Jreverse) of 246 at ±2 V, lower dark current density ( Jdark) of 3.5× 10-7 A/cm2 at a reverse bias of 2 V, and superior ultraviolet (UV) sensitivity ( IUV/Idark) of 16.23 than those without the SiO2 layer ( Jforward/Jreverse = 44, Jdark = 4.7× 10-6 A/cm2 , and IUV/Idark = 5.5). The improved performance was mainly due to the ultrathin inserted SiO2 layer that builds a barrier height to minimize the transmission probability of low-energy carriers, leading to the enhancement of the UV sensing characteristics.
- Nickel Oxide (NiO)
- Zinc Oxide (ZnO)