EUV and SXR sources based on discharge produced plasma

EUV sources based on discharge produced plasma (DPP), one of which is based on xenon gas jet discharge and the other is based on laser assisted tin discharge, are being developed for the next generation lithography. To get a high power source demanded by manufacturers, the understanding of pinch dynamics corresponding to emission is important and hence fundamental investigation, such as the simulation of gas density distribution or the measurement of electron temperature and density, is conducted. Soft X-ray laser using recombination scheme is also being studied to realize a shorter wavelength nitrogen laser at 13.4 nm. The results of spectroscopic measurement are shown.