Marc A. Klosner

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.

High-power plasma discharge source at 13.5 nm and 11.4 nm for EUV lithography

An intense pulsed capillary discharge source operating at 13.5 nm and 11.4 nm, suitable for use in conjunction with Mo:Si or Mo:Be coated optics, has produced an average power of approximately 1.4W within a 0.3 nm emission bandwidth from the end of the capillary when operated at a repetition rate of 100 Hz. The source is comprised of a small capillary discharge tube filled with xenon gas at low pressure to which electrodes are attached at each end. When a voltage is applied across the tube, an electrical current is generated for short periods within the capillary that produces highly ionized xenon ions radiating in the EUV. Issues associated with plasma bore erosion are currently being addressed from the standpoint of developing such a source for operation at repetition rates of greater than 1 kHz.

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.

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.