Xenon capillary discharge extreme-ultraviolet source emitting over a large angular range.

We describe a capillary discharge source configuration, allowing for collection of extreme-ultraviolet (EUV) radiation at large off-axis angles, without the need for an EUV window. Operating with xenon gas, the source emits intensely within the EUV spectral region at 11.3 and 13.5 nm. When coupled with a high-collection-efficiency optical system, this source may be suitable for a number of high-average-power EUV imaging applications.

High-Temperature Lithium Metal-Vapor Capillary Discharge Extreme-Ultraviolet Source at 13.5 nm.

We describe a high-temperature lithium extreme-ultraviolet (EUV) source based on a capillary discharge configuration that was developed for operating with metal vapors. The source produces narrow-band emission at 13.5 nm in the EUV spectral region, with emission intensity proportional to the lithium-vapor density. At an operating temperature of 725 degrees C, our measurements showed that, on axis, the source generated approximately 0.2 (mJ/2pi sr)/pulse at 13.5 nm.

Intense xenon capillary discharge extreme-ultraviolet source in the 10-16-nm-wavelength region.

We have observed intense extreme-ultraviolet emission, within the 10-16-nm-wavelength range, emitted by a xenon capillary discharge plasma. Within a 0.3-nm bandwidth centered at 13.5 nm the axial emission intensity was comparable with that from the brightest laser-produced plasma sources, and a similar intensity was measured at approximately 11.3 nm. This source could thus be suitable for extreme-ultraviolet imaging applications, such as extreme-ultraviolet lithography.

Intense plasma discharge source at 13.5 nm for extreme-ultraviolet lithography.

We measured an emission of 6 mJ/pulse at 13.5 nm produced by the Li(2+) Lyman-? transition excited by a fast capillary discharge, using a lithium hydride capillary. 75% of the energy emanated from a spot size of 0.6 mm. The emission is narrow band and would thus be useful in extreme-ultraviolet lithography imaging systems that use Mo:Si multilayer mirrors. The output within the bandwidth of Mo:Si mirrors was comparable with that of a laser-produced plasma (LPP), and the wallplug efficiency of 0.1% was nearly an order of magnitude better than that of a LPP.