Development of gas jet type Z-pinch EUV light source for lithography

A new gas jet type Z-pinch source of 13.5 nm radiation, which has the characteristics of a gas jet electrodes configuration and the scheme for radial extraction of extreme ultraviolet (EUV) light, has been developed. The gas jet type Z-pinch discharge has two nozzles and two diffusers. The EUV beam is collected from the side of pinch plasma, generated in between the inner nozzle and corresponding diffuser, at the radial direction. The design feature of the gas jet type Z-pinch source accommodates the cylindrical annular shape helium (He) gas curtain that is produced by the outer nozzle. The dimension of pinch plasma is FWHM diameter of 0.07 mm and length of 0.34 mm. The EUV output in 2 % bandwidth at 13.5 nm is 0.78 mJ/sr/pulse.