Low temperature processing of hybrid nanoparticulate Indium Tin Oxide (ITO) polymer layers and application in large scale lighting devices

We report on transparent conductive indium tin oxide (In2O3:Sn; ITO) nanoparticle films processed at a low temperature of 130 °C for the application in lighting devices using spin coating and doctor blading techniques. Major emphasis is put on the beneficial application of the particular transparent electrode material for the fabrication of patterned large area electroluminescence lamps. In order to improve film properties like adhesion and conductivity, hybrid nanoparticle–polymer blends out of ITO particles and organic film-forming agent polyvinylpyrrolidone (PVP) and the organofunctional coupling agent 3-methacryloxypropyltrimethoxysilane (MPTS) have been developed. The layers were cured by UV-irradiation, which was also used for lateral structuring of the transparent, conductive electrode. Additional low-temperature heat treatment (T = 130 °C) in air and forming gas improved the electronic properties. While pure ITO nanoparticulate layers processed at 130 °C exhibited conductance of up to 3.1 Ω− 1 cm− 1, the nanocomposite coatings showed a conductance of up to 9.8 Ω− 1 cm− 1. Corresponding layers with a sheet resistance of 750 Ω/□ were applied in electroluminescent lamps.