Femtosecond Laser Texturing of DLC based coatings by DLW Method with Sub-micrometer Precision

Abstract The enhancement of functional surfaces by laser texturing has been investigated in many studies; however, it has been often applied to the substrate. New laser technologies, such as the direct laser writing (DLW) method using a femtosecond laser, allow the production of extremely precise textures into both substrates and thin films. This paper investigates two distinct methods producing various textures: (i) the substrate is textured before the deposition of the diamond-like carbon coating (DLC), and (ii) the texture is produced into DLC coating deposited on a polished substrate. Our goal was to achieve identical topography in both cases; the textured area was as large as 170 mm2. The textured topography was assessed by 3D laser scanning microscope, which confirmed the repeatability of fs laser processing. Raman spectroscopy mapping, SEM, and XPS were combined to investigate the effect of laser processing on DLC coating in terms of oxidation or structural changes.