Modeling of a filamental discharge formation and development in ArF excimer laser

Dynamics of a constricted filamental discharge in a discharge-excited ArF excimer laser has been examined using a two dimensional fluid model. An entire process of the filamental discharge, from its initiation and development to extinction, is shown. The filamental discharge is triggered at protrusions which would always exist on cathode surfaces, and develops in the direction of the anode assisted by the high field induced by space charge. The gas temperature in the filamental discharge in the vicinity of the cathode is found to rise. This temperature is shown to plays an important role in development of the filamental discharge. The effect of preionization electron density n(e0) is also examined, and significant development of the filamental discharge toward the anode is seen when the n(e0) becomes lower. The results are examined properly in connection with experimental observations.