Abstract: An EUV plasma formation target delivery system and method is disclosed which may comprise: a target droplet formation mechanism comprising a magneto-restrictive or electro-restrictive material, a liquid plasma source material passageway terminating in an output orifice; a charging mechanism applying charge to a droplet forming jet stream or to individual droplets exiting the passageway along a selected path; a droplet deflector intermediate the output orifice and a plasma initiation site periodically deflecting droplets from the selected path, a liquid target material delivery mechanism comprising a liquid target material delivery passage having an input opening and an output orifice; an electromotive disturbing force generating mechanism generating a disturbing force within the liquid target material, a liquid target delivery droplet formation mechanism having an output orifice; and/or a wetting barrier around the periphery of the output orifice.

Abstract: An EUV target delivery system and method are disclosed which may comprise: a target material purification system connected to deliver liquid target material comprising: a first container and a second container in fluid contact with the target material reservoir; a filter intermediate the first chamber and the second chamber; a liquid target material agitation mechanism, or at least one purification chamber containing the target material in a form reactive with impurities contained in the inert gas reacting with such impurities and removing from the inert gas the impurities, or providing an evaporation chamber in fluid communication with an impurity chamber and with a target droplet mechanism liquid target material reservoir and containing liquid source material; heating the liquid source material to a first temperature sufficient to evaporate a first set of contaminants; heating the liquid source material to a second temperature sufficient to evaporate lithium.

Abstract: An apparatus and method is disclosed which may comprise a laser produced plasma EUV system which may comprise a drive laser producing a drive laser beam; a drive laser beam first path having a first axis; a drive laser redirecting mechanism transferring the drive laser beam from the first path to a second path, the second path having a second axis; an EUV collector optical element having a centrally located aperture; and a focusing mirror in the second path and positioned within the aperture and focusing the drive laser beam onto a plasma initiation site located along the second axis. The apparatus and method may comprise the drive laser beam is produced by a drive laser having a wavelength such that focusing on an EUV target droplet of less than about 100 ?m at an effective plasma producing energy if not practical in the constraints of the geometries involved utilizing a focusing lens. The drive laser may comprise a CO2 laser. The drive laser redirecting mechanism may comprise a mirror.

Abstract: An EUV light generation system and method is disclosed that may comprise a droplet generator producing plasma source material target droplets traveling toward the vicinity of a plasma source material target irradiation site; a drive laser; a drive laser focusing optical element having a first range of operating center wavelengths; a droplet detection radiation source having a second range of operating center wavelengths; a drive laser steering element comprising a material that is highly reflective within at least some part of the first range of wavelengths and highly transmissive within at least some part of the second range of center wavelengths; a droplet detection radiation aiming mechanism directing the droplet detection radiation through the drive laser steering element and the lens to focus at a selected droplet detection position intermediate the droplet generator and the irradiation site.

Abstract: An EUV plasma formation target delivery system and method is disclosed which may comprise: a target droplet formation mechanism comprising a magneto-restrictive or electro-restrictive material, a liquid plasma source material passageway terminating in an output orifice; a charging mechanism applying charge to a droplet forming jet stream or to individual droplets exiting the passageway along a selected path; a droplet deflector intermediate the output orifice and a plasma initiation site periodically deflecting droplets from the selected path, a liquid target material delivery mechanism comprising a liquid target material delivery passage having an input opening and an output orifice; an electromotive disturbing force generating mechanism generating a disturbing force within the liquid target material, a liquid target delivery droplet formation mechanism having an output orifice; and/or a wetting barrier around the periphery of the output orifice.

Abstract: A laser produced plasma (“LPP”) extreme ultraviolet (“EUV”) light source and method of operating same is disclosed which may comprise an EUV plasma production chamber having a chamber wall; a drive laser entrance window in the chamber wall; a drive laser entrance enclosure intermediate the entrance window and a plasma initiation site within the chamber and comprising an entrance enclosure distal end opening; at least one aperture plate intermediate the distal opening and the entrance window comprising at least one drive laser passage aperture. The at least one aperture plate may comprise at least two aperture plates comprising a first aperture plate and a second aperture plate defining an aperture plate interim space. The at least one drive laser aperture passage may comprise at least two drive laser aperture passages.

Abstract: An EUV light source is disclosed which may comprise a plurality of targets, e.g., tin droplets, and a system generating pre-pulses and main-pulses with the pre-pulses for irradiating targets to produce expanded targets. The system may further comprise a continuously pumped laser device generating the main pulses with the main pulses for irradiating expanded targets to produce a burst of EUV light pulses. The system may also have a controller varying at least one pre-pulse parameter during the burst of EUV light pulses. In addition, the EUV light source may also include an instrument measuring an intensity of at least one EUV light pulse within a burst of EUV light pulses and providing a feedback signal to the controller to vary at least one pre-pulse parameter during the burst of EUV light pulses to produce a burst of EUV pulses having a pre-selected dose.

Abstract: A source material dispenser for an EUV light source is disclosed that comprises a source material reservoir, e.g. tube, that has a wall and is formed with an orifice. The dispenser may comprise an electro-actuatable element, e.g. PZT material, that is spaced from the wall and operable to deform the wall and modulate a release of source material from the dispenser. A heat source heating a source material in the reservoir may be provided. Also, the dispenser may comprise an insulator reducing the flow of heat from the heat source to the electro-actuatable element. A method of dispensing a source material for an EUV light source is also described. In one method, a first signal may be provided to actuate the electro-actuatable elements to modulate a release of source material and a second signal, different from the first, may be provided to actuate the electro-actuatable elements to unclog the orifice.

Abstract: An EUV light generation system and method is disclosed that may comprise a droplet generator producing plasma source material target droplets traveling toward the vicinity of a plasma source material target irradiation site; a drive laser; a drive laser focusing optical element having a first range of operating center wavelengths; a droplet detection radiation source having a second range of operating center wavelengths; a drive laser steering element comprising a material that is highly reflective within at least some part of the first range of wavelengths and highly transmissive within at least some part of the second range of center wavelengths; a droplet detection radiation aiming mechanism directing the droplet detection radiation through the drive laser steering element and the lens to focus at a selected droplet detection position intermediate the droplet generator and the irradiation site.

Abstract: An LPP EUV light source is disclosed having an optic positioned in the plasma chamber for reflecting EUV light generated therein and a laser input window. For this aspect, the EUV light source may be configured to expose the optic to a gaseous etchant pressure for optic cleaning while the window is exposed to a lower gaseous etchant pressure to avoid window coating deterioration. In another aspect, an EUV light source may comprise a target material positionable along a beam path to participate in a first interaction with light on the beam path; an optical amplifier; and at least one optic directing photons scattered from the first interaction into the optical amplifier to produce a laser beam on the beam path for a subsequent interaction with the target material to produce an EUV light emitting plasma.

Abstract: Systems and methods are disclosed for cleaning a chamber window of an extreme ultraviolet (EUV) light source. The window may have an inside surface facing a chamber interior and an opposed outside surface and the light source may generate debris by plasma formation. For the system, a subsystem may be positioned outside the chamber and may be operable to pass energy through the window to heat debris accumulating on the inside surface of the window. In a first embodiment, the subsystem may place a flowing, heated gas in contact with the outside surface of the window. In another embodiment, electromagnetic radiation may be passed through the window.

Abstract: An EUV light source is disclosed which may comprise a laser source generating a laser beam and a source material, e.g. tin, SnBr4, SnBr2, SnH4, tin-gallium alloys, tin-indium alloys, tin-indium-gallium alloys or combinations thereof, that is irradiated by the laser beam to form a plasma and emit EUV light. The EUV light source may also comprise a beam dump positioned to receive the laser beam and a system controlling the temperature of the beam dump within a pre-selected range. In one embodiment, the source material may be irradiated at an irradiation zone and the source may further comprises a receiving structure formed with a surface shaped to receive source material ejected from the irradiation zone and direct the received source material for subsequent collection. The receiving structure and the beam dump may be formed as a single integrated unit.

Abstract: A laser light source is disclosed having a laser oscillator producing an output beam; a first amplifier amplifying the output beam to produce a first amplified beam, and a second amplifier amplifying the first amplified beam to produce a second amplified beam. For the source, the first amplifier may have a gain medium characterized by a saturation energy (Es, 1) and a small signal gain (go, 1); and the second amplifier may have a gain medium characterized by a saturation energy (Es, 2) and a small signal gain (go, 2), with (go, 1)>(go, 2) and (Es, 2)>(Es, 1). In another aspect, a laser oscillator of a laser light source may be a cavity dumped laser oscillator, e.g. a mode-locked laser oscillator, q-switched laser oscillator and may further comprising a temporal pulse stretcher.

Abstract: Systems and methods are disclosed for protecting an EUV light source plasma production chamber optical element surface from debris generated by plasma formation. In one aspect of an embodiment of the present invention, a shield is disclosed which comprises at least one hollow tube positioned between the optical element and a plasma formation site. The tube is oriented to capture debris while allowing light to pass through the tube's lumen via reflection at relatively small angles of grazing incidence. In another aspect of an embodiment of the present invention, a shield is disclosed which is heated to a temperature sufficient to remove one or more species of debris material that has deposited on the shield. In yet another aspect of an embodiment of the present invention, a system is disclosed which a shield is moved from a light source plasma chamber to a cleaning chamber where the shield is cleaned.