Behavior of debris from laser-produced plasma for extreme ultraviolet light source measured by laser imaging technique

Abstract

The behavior of debris generated from a laser-produced plasma (LPP) for the extreme ultraviolet light source at 13.5nm has been studied using a laser induced fluorescence (LIF) imaging system. Tin (Sn) LPPs were produced by irradiating a flat Sn plate and Sn thin films perpendicularly with a Nd:YAG laser beam. When a thin Sn film was used as a target material, the depletion of the Sn atoms was clearly observed along the Nd:YAG laser beam. The LIF system was also used for visualizing the sputtering process of a mirror substrate by the fast ions generated from the plasma.