Ultra-thin glass (UTG) with thicknesses less than 200 µm is a new flexible substrate material for electronics and display applications. Superior material properties, like the excellent barrier to water and oxygen, the temperature stability and low surface roughness open up new possibilities for transparent electronics and display technology. The usage is being currently pushed forward, to substitute polymers as encapsulation materials in ultra-thin packages or OLED devices.
Physical vapour deposition (PVD) are common methods to realize thin-films electrical and optical functionality. The intrinsic stresses of the thin-films influence the mechanical properties and reliability of the layer-substrate compound.
In this study DC magnetron sputtering with an in-line sheet-to-sheet system was used for thin ITO coatings on different UTG substrates with a thickness of 50 µm and 100 µm. In order to improve the optical and the electrical properties, we used flash lamp annealing (FLA) in millisecond range of 2 ms to 10 ms as an ultra-fast post-annealing method. We observed a decrease in the sheet resistance from 90 Ω to 18 Ω after FLA. The correlation of process parameters for layer deposition on the electrical properties for the ITO thin-films and the influences on the intrinsic film stress have been investigated.