Hierarchical laser patterning of indium tin oxide thin films

Multiscale laser patterning of indium tin oxide thin films using the combination of direct laser interference patterning (DLIP) and laser induced periodic surface structuring (LIPSS) was studied. By balancing DLIP and LIPSS, structures in an ordered hierarchical pattern consisting of 75 nm LIPSS, 650 nm DLIP, and 50 µm laser spot size were demonstrated. The effects of laser fluence on the DLIP, LIPSS, and grain growth are discussed. The anisotropic conductance due to LIPSS was shown to exceed 50,000:1. Infrared reflectance measurements indicated that the anisotropy was uniform across the laser patterned samples.