Fabrication of Au/ZnO Schottky nanodiode using mesoporous silica film as template

Au/ZnO Schottky nanodiode is prepared by two-step electrodeposition, using mesoporous silica (MPS) film as template. Nano-ZnO is firstly deposited in the pores of MPS film, which achieves enhanced conductivity and enables continued electrodeposition of Au to form an Au/ZnO Schottky nanodiode. Current-voltage (I-V) curves of Au/ZnO nanodiode are recorded under a switched UV-light with the wavelength of 365 nm. The characteristic I-V curves show rectifying behavior in the dark, and present more linear Ohmic response upon UV exposure, which might be caused by the lowered Schottky barrier height and narrowered Schottky barrier width. In addition, fast increased forward-current and lowered breakdown voltage are observed from I-V curves of Au/ZnO Schottky nanodiode. The ideality factor of the Au/ZnO Schottky diode is determined to be approximately 8. These results suggest a different photocurrent-generation process, and provide experimental support to the model proposed in ultrasmall Schottky diodes.