Hydrodynamics modeling of the dynamics of Sn droplet target for the EUV source

Sasaki, Akira

Improvement of the efficiency and output power of the EUV source is essential for the realization of the next generation micro-lithography. Recently, a high efficiency is obtained using the double pulse technique, where the Sn droplet is broken up into particles by the irradiation of the relatively weak pre-pulse laser. For the optimization of the source, we study methods for the modeling of pre-plasma formation including the solid/liquid to gas phase transition of Sn and particle emission. We study the equation of state of Sn and phase transition theoretically, and also study methods to calculate distribution of solid/liquid and gas phase after the phase transition. Results of test calculation of the evaporation hot Sn droplet will be shown.