Micro gratings written in ZnO:Al thin films using picosecond UV‐laser interference patterning

Diffraction micro gratings have been written in ZnO:Al thin films using a picosecond laser operating at 355 nm. Micro gratings of 20 µm diameter with a period of 860 nm show a groove depth up to 120 nm. The total transmittance of square‐centimeter‐size grating‐textured ZnO:Al films was almost unchanged after grating formation, while the sheet resistance increased moderately. The textured films reached haze values of 9% at 700 nm. This simple texturing method can be applied also to ZnO:Al films that cannot be texture etched.Illustration of the interfering laser beams and the resulting micro grating (left) and reflection from a micro grating array written in ZnO:Al on glass (right). (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)