Laser Direct Ablation of Indium Tin Oxide Films on Both Sides of Various Substrates

We demonstrate ablation of indium tin oxide (ITO) films onto both glass and polyethylene terephthalate (PET) substrates, using a Q-switched diode-pumped neodymium-doped yttrium vanadate laser (Nd:YVO4, λ = 1064 nm) incident on both the front and back sides of the substrate. From scanning electron microscope (SEM) images and depth profile data, ITO patterns that were laser-ablated onto glass from the back side showed a larger abrupt change in the ablated line width than those ablated from the front. However, there were only slight differences in ablated line widths due to the direction of the incident laser beam. We provide a possible explanation in terms of several factors: dispersion of laser beam energy through the substrate, overlapping of each laser beam spot due to scanning speed, and the thickness of glass and PET substrates.