Impact of the meso-PSi substrate on ZnO thin films deposited by spray pyrolysis technique for UV photodetectors

Abstract

ZnO thin films were successfully deposited via spray pyrolysis technique over various substrates, including glass, silicon, and mesoporous silicon (PSi). The effect of substrate type on the surface morphological, structural, and electrical properties of ZnO thin film was investigated. Scanning Electron Microscopy confirms the morphology of the meso-PSi substrate and displays the morphologies of the deposited ZnO. The (ZnO/PSi) heterojunction shows a porous ZnO layer with a large surface area by comparison to other structures. The patterns of X-ray Diffraction exposed that the deposited ZnO films have a hexagonal wurtzite polycrystalline structure. Ultraviolet (UV) metal-semiconductor-metal photodetectors have been investigated. The fabricated (ZnO/PSi) UV photodetector showed much higher photocurrent than other structures.