Spatial coherence measurement of a high average power table-top soft X-ray laser

Extreme ultraviolet lithography with table top lasers

“…For a 36 cm long gain medium, a coherence radius of 550 mm measured at 1.5 m from the source that includes almost half of the entire laser power is obtained. The coherence radius was measured analyzing the fringe visibility of the interference fringes obtained when a mask with two pinholes at different separations was placed at selected distances from the source [65,66]. The coherence radius R c characterizes the transverse coherence of the laser beam, and was defined following the convention of coherence area used by Goodman [67].…”

Tabletop soft x-ray holography with sub-200-nm spatial resolution

“…[18,19] The high temporal and spatial coherence of the table top SXR laser permits the recording of large NA holograms for high resolution holographic imaging. [20,21] Using the Gabor's geometry shown in figure 1 two holograms with two different NA were obtained varying the distance object-hologram z p . The two selected distances were z p ≈ 4 mm and z p ≈ 120 µm.…”

Patterning of nano-scale arrays by table-top extreme ultraviolet laser interferometric lithography

“…The 27 cm long capillary discharge plasma columns used in this experiment generates a laser beam that has a spatial coherence length of approximately 570μm measured at the experiment chamber located at 1.7 m from the exit of the laser. The spatial coherence length can be further increased using a longer plasma [17,18] IL was implemented by illuminating a flat mirror in the Lloyd's configuration with the EUV laser output. In this configuration, part of the laser beam impinges on the mirror at an incidence angle θ and is reflected to interfere with the remaining un-deflected portion of the beam, as illustrated in Fig.…”