Development of a Collective Thomson Scattering System for Diagnostics of Laser Produced EUV Plasmas

After the 32 nm half-pitch technology node, extreme ultraviolet (EUV) lights are going to be used for semiconductor lithography. In order to diagnose laser produced plasmas for EUV light sources, a collective laser Thomson scattering system has been developed. Clear ion term spectra were observed from laser produced carbon plasmas and spatiotemporal evolutions of electron density, electron temperature and averaged ionic charge in these plasmas were successfully measured.