Regensburg 2007 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

O: Fachverband Oberflächenphysik

O 17: Poster Session I (Nanostructures at Surfaces; Metal Substrates: Epitaxy and Growth; Methods: Scanning Probe Techniques; Phase Transitions)

O 17.69: Poster

Monday, March 26, 2007, 17:30–20:30, Poster C

Nanoparticle removal by laser induced acoustic waves — •Tobias Geldhauser, Florian Merkt, Florian Ziese, Johannes Boneberg, and Paul Leiderer — Fachbereich Physik, Universität Konstanz, Fach M676, 78457 Konstanz

Different approaches can be used for particle removal from surfaces like Ultra-/Megasonic or Dry/ Steam Laser Cleaning. Here we analyze an alternative approach where a laser pulse hits the back of a wafer and thereby initiates a bulk acoustic wave which travels towards the opposing wafer surface, leading to surface displacements and particle removal. We relate the cleaning efficiency for colloidal contaminants of different diameters (measured by light scattering) to the surface expansion, and hence the acceleration, which is measured with a ns-time-resolved Michelson Interferometer. In order to develop a model for the removal process of the particles we measure in addition the detachment velocity of the particles by a light-scattering technique.