Characterization of soft X-ray source using laser-irradiated gas puff targets

Laser-produced plasmas have been attractive compact sources of intense soft X-ray radiation applicable to various fields of researches, such as X-ray lithography, X-ray microscopy, atomic physics, and material science. The laser-produced plasma source consists of a laser system which produces high power radiation and a target that is placed inside a vacuum chamber to decrease strong absorption of soft X-rays in the air. The gas puff target is produced by pulsed injection of gas through a nozzle of a high-pressure valve into the vacuum chamber. The use of a fast acting electromagnetic valve allows creation of a high gas density region above the nozzle, and results in efficient absorption of the laser light and intense emission of X-rays comparable to the emission from a solid target.