Enhancement of the line X-ray emission from iron plasma is investigated by simulating laser irradiation of both porous and solid targets. Spectral line intensities are calculated for selected lines of the iron plasma within the extreme ultra-violet lithography wavelength range 13.3–13.7 nm. The calculations show that X-ray yield in porous targets can be enhanced significantly in comparison with solid density targets. The results also show that for specified conditions of the driving laser, there are optimums conditions of the porous target in which maximum yield can be obtained.
