Pulsed Laser Interference Patterning of Metallic Thin Films

Abstract

Pulsed laser interference is applied to metallic and semiconductor thin films in the thickness range of 40-100 nm. At intensities which induce local melting we can observe local retraction of the molten material towards the unmolten areas due to dewetting. Thus micropatterning of surface gets feasible. Although this dewetting induced retraction should be a common behaviour of metals on oxide surfaces, two groups of materials can be distinguished. In the first group the former molten areas get completely blank of metal while in the second group a material droplet remains in the center of the molten area. We show that this behaviour can be attributed to a distinctly different way of liquid movement upon local melting.

High‐Speed Surface Structuring of Polycarbonate Using Direct Laser Interference Patterning: Toward 1 m2 min−1 Fabrication Speed Barrier

“…Due to this characteristic, the pattern geometry does not only depend on the angle between the laser beams and the laser wavelength, but relies also on the conditions used for processing the material (feed rate v and repetition rate f p ). In fact, more complex surface patterns can be produced using the same two‐beam configuration.…”

“…A fabrication method that provides both high resolutions (even below the micrometer scale) and high fabrication speed is direct laser interference patterning (DLIP) . This technique allows the processing of different pattern geometries (e.g., line‐, dot‐, or cross‐like pattern) on a wide variety of materials (polymers, metals, and coatings) at fabrication speeds up to approximately 0.1 m 2 min −1 . The interference pattern is obtained by overlapping a certain amount of coherent laser beams.…”