Continuous Manufacture of Submicron Thick Ceramic Green Tapes and Coatings Demonstrated for TCO Nano Particles

Abstract

This presentation introduces a new technique to manufacture continuously submicron thick ceramic green tapes and coatings from nano particulate suspensions. A profiled steel rod is used to coat large areas with a very low film thickness of down to 250 nm. This technique can easily be scaled up and is therefore suitable for mass production at high throughput and low cost. The profile rod technique could be a method to overcome the limit of the tape casting process and therefore this technique exhibits an enormous economical potential. The technique is demonstrated at the example of nano particulate indium tin oxide (ITO) and zinc oxide (ZnO) particles, which are both transparent conductive oxides (TCOs) and therefore interesting materials for printed displays etc. Nano particles from Evonik Degussa GmbH were first dispersed and stabilized in organic solvents. Subsequently, dispersions as well as slurries were prepared. Their rheological and wetting behavior were studied and the effect on the microstructure of the resulting layer was evaluated. Furthermore, the influence of the processing parameters during coating on the layer quality was analyzed. Finally, the functionality of the printed layers was proven by electrical measurements as well as the assembly of electron devices.