Abstract: Techniques are described that enhance power from an extreme ultraviolet light source with feedback from a target material that has been modified prior to entering a target location into a spatially-extended target distribution or expanded target. The feedback from the spatially-extended target distribution provides a nonresonant optical cavity because the geometry of the path over which feedback occurs, such as the round-trip length and direction, can change in time, or the shape of the spatially-extended target distribution may not provide a smooth enough reflectance. However, it may be possible that the feedback from the spatially-extended target distribution provides a resonant and coherent optical cavity if the geometric and physical constraints noted above are overcome. In any case, the feedback can be generated using spontaneously emitted light that is produced from a non-oscillator gain medium.

Abstract: Techniques are described that enhance power from an extreme ultraviolet light source with feedback from a target material that has been modified prior to entering a target location into a spatially-extended target distribution or expanded target. The feedback from the spatially-extended target distribution provides a nonresonant optical cavity because the geometry of the path over which feedback occurs, such as the round-trip length and direction, can change in time, or the shape of the spatially-extended target distribution may not provide a smooth enough reflectance. However, it may be possible that the feedback from the spatially-extended target distribution provides a resonant and coherent optical cavity if the geometric and physical constraints noted above are overcome. In any case, the feedback can be generated using spontaneously emitted light that is produced from a non-oscillator gain medium.

Abstract: A deep ultraviolet light source includes a master oscillator producing a seed light beam; a regenerative ring amplifier receiving the seed light beam from the master oscillator and outputting an output light beam, the regenerative ring amplifier including a set of optical components that define a plane of a closed ring; and a divergence control device within the master oscillator or between the master oscillator and the regenerative ring amplifier and configured to reduce a divergence of the output light beam along a normal direction, the normal direction being perpendicular to the plane of the ring.