Experimental study of xenon and tin discharge produced plasma EUV light source

Recently, a lot of progresses have been made in the field of gas discharge and laser assisted extreme ultraviolet (EUV) light sources. In order to realize the EUV lithography, we have been developing the discharge produced plasma EUV light source with either Xe or Sn fuels. A Xe gas jet Z-pinch discharge system has been developed for generating high quality debris-free EUV emission. A 25kA pulsed power supply system has been constructed and introduced. Observation of optical characteristics are presently in progress. Also, the laser triggered discharge produced plasma with Sn electrode system has been constructed. In our system, after Nd-YAG laser was irradiated on Sn electrode surface for triggering the main discharge, EUV radiation will occur from the generated Sn plasma between electrodes and be collected radially. The maximum discharge current of about 6 kA with a pulse width of 500 ns was supplied to anode-cathode gap. In present study, EUV radiation emitted from gas jet Z- pinch Xe plasma and laser triggered Sn discharge produced plasma was quantitatively measured using an in-band calorimeter. Time-resolved in-band source image measurement was also conducted using a pinhole camera system.