High-brightness laser-induced EUV source based on tin plasma with an unlimited lifetime of electrodes

Characteristics of a source of laser-induced radiation in the extreme ultraviolet (EUV) range, obtained in a discharge between two jets of liquid tin, are investigated. The possibility of designing a high-brightness EUV source on this basis for employing in mask inspection techniques in projection EUV lithography is demonstrated. The average efficiency of converting the electric energy to radiation in the spectral range of 13.5±0.135 nm is approximately 2%/2π sr with the size of emitting plasma 0.2±0.35 mm. The possibility of producing a EUV source with a brightness of about 200&nmbsp;W (mm²sr)^-1 is demonstrated.