Regensburg 2007 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DS: Fachverband Dünne Schichten

DS 4: Nanoengineered Thin Films

DS 4.6: Talk

Monday, March 26, 2007, 12:30–12:45, H34

Nanopatterning by Phase Mask Projection Laser Ablation — •Marisa Mäder, Thomas Höche, Jürgen Gerlach, and Rico Böhme — Leibniz Institute of Surface Modification, Permoserstrasse 15, 04318 Leipzig, Germany

Nanostructures attached to a substrate promise optical and electronic applications like LEDs or diodes. Moreover, for Nanodots applications in various probing techniques (including Surface Enhanced Raman Spectroscopy) are also aspired. So far, however, the fabrication process of most nanostructures is still very complex and often too costly for industrial use. An alternative, versatile, fast, and relatively easy process is the technique of laser ablation using phase-mask projection. Pulsed laser light with the wavelength of 248 nm is sent through a phase mask. The phase mask modulates the phase of the incident beam at defined positions. Using a Schwarzschild reflection objective, the resulting interference pattern is demagnified and projected onto a thin film. At positions where the intensity exceeds the ablation threshold of the film but not the substrate, material is ablated from the substrate. Different shapes of nanostructures can be fabricated this way, depending on the pattern of the phase mask. GaN nanowires were produced with a striped mask while Au nanodots were fabricated using a checkerboard mask. In principle, every combination of thin film and substrate material is possible, as long as the ablation thresholds are matching, respectively.