Looking at surfaces with cluster ion beams

Various mass-spectrometry-based techniques are widely used to characterize the near-surface region of a solid. The idea is to stimulate the desorption of surface species with some type of energetic input, such as an intense laser pulse, strong electric field, or energetic ion beam. Detection of the elemental or molecular species by mass spectrometry can provide a selective and sensitive measure of surface chemistry, with applications ranging from nanotechnology to biology.