Fabrication of Flexible Metal Oxide Thin Film Transistor By Indigenously Developed Spray Pyrolysis Unit

Abstract

The deposition of polyvinyl alcohol (PVA) dielectrics and semiconductor Zinc oxide (ZnO) thin film is developed by custom designed spray pyrolysis unit. The solutions for spray are prepared by PVA and zinc acetate dehydrated as precursor materials. These solutions are deposited on a substrate such as Aluminium coated polyimide and polyimide film The Aluminium is used as Source and drain electrodes. PVA and ZnO deposited on these electrodes is act as the gate oxide and channel layers for thin film transistor (TFT). Gate electrodes are deposited by thermal evaporation of Al using shadow mask method. Finally, top gated TFT is fabricated. Results: The morphology of the films was characterized by FESEM which confirmed that the film was uniform with no cracks. The XRD results are confirm the amorphous nature of ZnO thin film. The PVA coatings are also examined for electrical properties like C-V. The thickness and roughness of films were measured using optical Profilometer. The optical studies of the film are studied and the band gap is calculated using Tauc plot. A study has been performed on ZnO for its electrical characteristics such as mobility and resistivity. The TFT characteristics like input and output has been carried out. Keywords: TTF, Spray pyrolysis, PVA, ZnO, Figure 1