The effect of laser patterning parameters on fluorine-doped tin oxide films deposited on glass substrates

The purpose of this study is to pattern the fluorine-doped tin oxide thin film deposited on the soda-lime glass substrates for touch screen applications by ultraviolet laser. The patterned film structures provide the electrical isolation and prevent the electrical contact from each region for various touch screens. The surface morphology, edge quality, three-dimensional topography, and profile of isolated lines and electrode structures after laser patterning were measured by a confocal laser scanning microscope. Moreover, a four-point probe instrument was used to measure the sheet resistance before and after laser patterning on film surfaces and also to discuss the electrical property at different laser spot overlaps. After laser patterning, a high overlapping area of laser spot was used to pattern the electrode layer on film surfaces that could obtain an excellent machined quality of edge profile. All sheet resistance values of film surfaces near the isolated line edge were larger than the original ones. Moreover, the sheet resistance values increased with increasing laser spot overlapping area.