A metal reuse system for an extreme ultra violet (EUV) radiation source apparatus includes a first metal collector for collecting metal from vanes of the EUV radiation source apparatus, a first metal storage coupled to the first metal collector via a first conduit, a metal droplet generator coupled to the first metal storage via a second conduit, and a first metal filtration device disposed on either one of the first conduit and the second conduit.

An initial pulse of radiation is generated; a section of the initial pulse of radiation is extracted to form a modified pulse of radiation, the modified pulse of radiation including a first portion and a second portion, the first portion being temporally connected to the second portion, and the first portion having a maximum energy that is less than a maximum energy of the second portion; the first portion of the modified pulse of radiation is interacted with a target material to form a modified target; and the second portion of the modified pulse of radiation is interacted with the modified target to generate plasma that emits extreme ultraviolet (EUV) light.

Methods and systems for realizing a high brightness, compact x-ray source suitable for high throughput, in-line x-ray metrology are presented herein. A compact electron beam accelerator is coupled to a compact undulator to produce a high brightness, compact x-ray source capable of generating x-ray radiation with wavelengths of approximately one Angstrom or less with a flux of at least 1e10 photons/s*mm^2. In some embodiments, the electron path length through the electron beam accelerator is less than ten meters and the electron path length through the undulator is also less than 10 meters. The compact x-ray source is tunable, allowing for adjustments of both wavelength and flux of the generated x-ray radiation. The x-ray radiation generated by the compact x-ray source is delivered to the specimen over a small spot, thus enabling measurements of modern semiconductor structures.

Methods and systems for realizing a high brightness, compact x-ray source suitable for high throughput, in-line x-ray metrology are presented herein. A compact electron beam accelerator is coupled to a compact undulator to produce a high brightness, compact x-ray source capable of generating x-ray radiation with wavelengths of approximately one Angstrom or less with a flux of at least 1e10 photons/s*mm^2. In some embodiments, the electron path length through the electron beam accelerator is less than ten meters and the electron path length through the undulator is also less than 10 meters. The compact x-ray source is tunable, allowing for adjustments of both wavelength and flux of the generated x-ray radiation. The x-ray radiation generated by the compact x-ray source is delivered to the specimen over a small spot, thus enabling measurements of modern semiconductor structures.

The invention relates to a droplet dispensing device (4) comprising a reservoir (9) for containing a liquid medium (10), an outlet (11) for dispensing droplets of said liquid medium (10) from said reservoir (9), an actuation means (12) for generating and transmitting a mechanical oscillation at an excitation frequency, and a resonant structure comprising a piston (15) coupled to said actuation means (12) for transmitting said mechanical oscillation to the liquid medium (10) contained in said reservoir (9) such that droplets are formed from said liquid medium (10), wherein a resonance frequency of said resonant structure is sufficiently close to said excitation frequency, such that resonance occurs.

The invention further relates to a UV or X-ray light source, comprising a droplet dispensing device (4) according to the invention, and a method for providing a stream, in particular a monodisperse stream, of droplets by means of the droplet dispensing device (4).

A light source with radiating plasma sustained in the gas-filled chamber by a focused beam of CW laser. The gas is inert gas with a purity of at least 99.99%. The chamber contains a metal housing with at least one window made of MgF.sub.2 for outputting a plasma radiation. Each window is located in a hole of the housing on the end of a sleeve and is soldered to the sleeve by means of glass cement, and each sleeve is welded to the hole of the metal housing on the outside seam. The sleeves and the housing are made of an alloy with a coefficient of linear thermal expansion (CLTE), matched with the CLTE of the MgF.sub.2 crystal in the direction perpendicular to the optical axis of the MgF.sub.2 crystal. The technical result consists in expanding the radiation spectrum of the light source into the VUV region.

A droplet generator nozzle (800, 820/830) includes a metal body (802, 822), a metal fitting (812, 823/833) arranged adjacent to the metal body, and a capillary (804, 824/834) comprising a first end and a second end. The first end of the capillary is disposed within the metal fitting, and the capillary is configured to eject initial droplets of a material from the second end of the capillary. The droplet generator nozzle further includes an electromechanical element (808 828/838) disposed within the metal body and coupled to the first end of the capillary and a fastener element (810) configured to clamp around a portion of the metal body and around the metal fitting. The electromechanical element is configured to apply a change that affects droplet generation from the capillary. The second end of the capillary protrudes out from an opening in the fastener element of the droplet generator nozzle. Droplet generator nozzle 830 of FIG. 8C represents the embodiment shown in FIG. 8B, in a cross section orthogonal to the cross section shown in FIG. 8B.

A laser-plasma-based acceleration system includes a focusing element and a laser pulse emission directing a laser beam to the focusing element to such that laser pulses transform into a focused beam and a chamber defining a nozzle having a throat and an exit orifice, emitting a critical density range gas jet from the exit orifice for laser wavelengths ranging from ultraviolet to the mid-infrared. the critical density range gas jet intersects the focused beam at an angle and in proximity to the exit orifice of the nozzle to define a point of intersection between the focused beam and the critical density range gas jet. In intersection with the critical density range gas jet, the pulsed focused beam drives a laser plasma wakefield relativistic electron beam. A corresponding method of laser-plasma-based acceleration is also described. The critical density range may include 2×10.sup.20 cm.sup.−3 to 5×10.sup.21 cm.sup.−3.

A method for monitoring a shock wave in an extreme ultraviolet light source includes irradiating a target droplet in the extreme ultraviolet light source apparatus of an extreme ultraviolet lithography tool with ionizing radiation to generate a plasma and to detect a shock wave generated by the plasma. One or more operating parameters of the extreme ultraviolet light source is adjusted based on the detected shock wave.

An amplified optical beam is provided to a region that receives a target including target material, an interaction between the amplified optical beam and the target converting at least some of the target material from a first form to a second form to form a light-emitting plasma; first data comprising information related to the amplified optical beam is accessed; second data comprising information related to the light-emitting plasma is accessed; and an amount of the target material converted from the first form to the second form is determined. The determination is based on at least the first data and the second data, and the second form of the target material is less dense than the first form of the target material.