Study of conducting ITO thin film deposition on flexible polyimide substrate using spray pyrolysis

Abstract

Nanostructured indium tin oxide (ITO) thin films have been grown by chemical spray pyrolysis method on flexible polyimide (PI) polymeric substrates at various temperatures (400, 450 and 500°C) using solutions of indium and tin chlorides as precursors. The composition, microstructure, surface morphology, thermal, electrical, and optical characteristics have been analysed by FT-IR, UV-Vis, X-ray diffraction, SEM, EDAX, atomic force microscopy, electrical measurements, TGA, etc. X-ray diffraction measurements employing Cu-Ka radiation showed that the ITO films were polycrystalline with a cubic bixbyite structure. An increment in average grain size, electrical conductivity and optical transmittance was observed at higher substrate temperature. ITO-coated films maintained the mechanical properties and stability of the pristine PI films. The adhesion between surface ITO layers and PI matrix was found acceptable. Graphical Abstract

Fabrication of highly conductive graphene/ITO transparent bi-film through CVD and organic additives-free sol-gel techniques

“…Tin (Sn) doped indium oxide, also known as indium tin oxide (ITO), is still employed in TCO-based industry, and offers the best combination of high optical transmittance and low electrical resistance, which properties are sensitive to the synthesis methods 10 – 12 . The aqueous precursor sol-gel technique has recently become of interest compared with the other synthesis methods of ITO, such as rf and dc sputtering, spray pyrolysis, vacuum evaporation, and pulsed laser deposition, due to the simple and low synthesis cost for bulk-scale production, possibility to change the film microstructure, chemical stoichiometry, and easy introduction of a dopant 11 – 15 . However, the use of flammable and environmentally harmful organic solvent and additives as stabilizers and binders during the preparation process of organic based sol-gel is not suitable for mass industrial production 12 , 16 .…”

Robustification of ITO nanolayer by surface‐functionalization of transparent biopolyimide substrates

“…Optical transmission spectra of the ITO‐coated films were taken in un‐polarized light at normal incidence in the wavelength range from 200 to 800nm, on a dual beam UV–vis spectrophotometer, taking air as a reference. The optical transparency was slightly improved after the coating with ITO which may be attributed to the better ITO structural homogeneity and crystallinity along the polyimide and lower defect density near the band edge [Figure (a)] . Kapton has an amber color due to the characteristic absorption fallout from UV to the visible region, caused by strong charge transfer (CT) interactions in the electron‐rich oxidianiline component with dianhydride moieties.…”

“…Of the various polymeric substrates, polyimides are well known as a promising plastic with high thermal/mechanical properties, exceptionally high chemical resistance, and low coefficient of thermal expansion, applicable for various advanced electronic and aerospace devices . Nano‐scaled coating of ITO thin‐layer on the plastics is a good method to keep the hybrid materials robust against mechanical deformation but thinner ITO layer can exhibit lower conductivity, plausibly due to higher sensitivity to structural defects which can disappear at high temperature treatment . Therefore, the successful deposition of ITO nanolayer on the polyimide substrate at high temperature offers a promising solution.…”

Synthesis and Characterization of Graphene/ITO Nanoparticle Hybrid Transparent Conducting Electrode

“…Indium tin oxide or tin-doped indium oxide (ITO) is recognized as a viable semiconducting metal oxide with high conductivity, chemical stability, good optical transparency, and excellent substrate adherence, making it a prime candidate in most advanced electronic applications [ 32 , 33 ]. The incorporation of ITO with graphene has attracted considerable attention for the development of hybrid materials.…”