Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2009 · 14 citations · 0 references
Natural SciencesChemistryMaterials ScienceOpticsRadiation DetectionRadiation MeasurementAtomic Force MicroscopyLaser OpticsLaser PhysicsLaser Surface ProcessingScanning Probe MicroscopySurface MicroscopyAtomic Force Microscopy AnalysisBeam FocusDifferential Interference Contrast MicroscopyFocal PositionFocusInteraction ParametersLaser Beam FocusingPolymethyl Methacrylate
The desktop capillary-discharge Ne-like Ar laser (CDL) providing 10-μJ nanosecond pulses of coherent 46.9-nm radiation with a repetition rate up to 12 Hz was developed and built at the Colorado State University in Fort Collins and then installed in Prague. The beam of the laser was focused by a spherical mirror covered with Si/Sc multilayer coating onto the surface of poly(methyl methacrylate) - PMMA. Interaction parameters vary by changing the distance between sample surface and beam focus. The samples were exposed to various numbers of shots. Analysis of damaged PMMA by atomic force (AFM) and Nomarski (DIC - differential interference contrast) microscopes allows not only to determine the key characteristics of the focused beam (e.g. Rayleigh's parameter, focal spot diameter, tight focus position, etc.) but also to investigate mechanisms of the radiation-induced erosion processes.