A compact ultrafast capillary discharge for EUV projection lithography

A novel type of ultrafast capillary discharge device was operated in Xenon at low pressure to obtain Extreme UV (EUV) radiation complying with the dem ands for future microlithography. After being triggered by means of the hol low cathode effect, the discharge starts on-axis and is then heated up effe ctively to a maximum temperature of 30 eV within a nanosecond timescale usi ng a stored energy of 0.5 J. During a pulse length of 5 ns concerning the E UV emission, the transient plasma inside the capillary whose aspect ratio i s much more than 10 emits mainly between 10 and 20 nm. The spectrum consist s of Xe VII to Xe X line radiation.