Innovative Strategies for the Removal of Organic Compounds in Nanoparticle ITO Layers

Layers of indium-tin-oxide (ITO) nanoparticles were deposited on the polymer substrates polypropylene and polyimide in ambient air. To decrease the electrical resistance of the deposited nanoparticle ITO layer precipitated organic compounds of the nanoink have to be removed. For temperature-resistant substrates a baking step is suitable for the removal of organic agents utilizing a hotplate. However, a hotplate baking is not suitable for organic substrates. In order to avoid thermal damage the polymer substrate laser based removal strategies were investigated utilizing ultraviolet and infrared laser irradiation. To further optimize the electrical conductivity of the ITO nanoparticle layer a final laser consolidation step is essential utilizing ultraviolet laser light provided by a KrF excimer laser.