Performance of the 13.5 nm PVC capillary discharge EUV source

A complete description of an ablative capillary discharge source emitting narrow band radiation at 13.5 nm is presented. The device is based on capillaries made of PVC with traces of Sn in the chemical additives used in the PVC production process. The strong emission is centered at 13.5 nm with a FWHM of 0.6 nm. The device is further characterized by a high conversion efficiency (0.45% at present and scalable above 2% with higher Sn concentration), low out-of-band XUV radiation and low divergence of the radiation cone (approximately ±20 mrad). By optimizing discharge parameters and capillary construction, the capillary lifetime is considerably extended, and is currently more that 300 shots on the average.