Abstract: A debris mitigation system for use in a radiation source. The debris mitigation system comprises a contamination trap. The contamination trap comprises a debris receiving surface arranged to receive liquid metal fuel debris emitted from a plasma formation region of the radiation source. The debris receiving surface is constructed from a material that reacts with the liquid metal fuel debris to form an intermetallic layer on the debris receiving surface.

Abstract: An EUV source for generating a beam of EUV radiation, has a droplet generator with a nozzle assembly to emit droplets of fuel from a nozzle towards a plasma formation location. The nozzle assembly receives the fuel from a reservoir. The nozzle assembly has a pump chamber receiving the fuel from the reservoir and an actuator to vibrate a membrane that forms a wall of the pump chamber. The wall is oriented perpendicularly to a direction wherein the nozzle emits the fuel. The nozzle assembly has first and second nozzle filters non-adjacently arranged in series in a path of the fuel from the pump chamber to the nozzle.

Abstract: A debris mitigation system for use in a radiation source. The debris mitigation system comprises a contamination trap. The contamination trap comprises a debris receiving surface arranged to receive liquid metal fuel debris emitted from a plasma formation region of the radiation source. The debris receiving surface is constructed from a material that reacts with the liquid metal fuel debris to form an intermetallic layer on the debris receiving surface.

Abstract: An EUV source for generating a beam of EUV radiation, has a droplet generator with a nozzle assembly to emit droplets of fuel from a nozzle towards a plasma formation location. The nozzle assembly receives the fuel from a reservoir. The nozzle assembly has a pump chamber receiving the fuel from the reservoir and an actuator to vibrate a membrane that forms a wall of the pump chamber. The wall is oriented perpendicularly to a direction wherein the nozzle emits the fuel. The nozzle assembly has first and second nozzle filters non-adjacently arranged in series in a path of the fuel from the pump chamber to the nozzle.

Abstract: A source collector apparatus for use in a lithographic apparatus includes a fuel droplet generator configured in use to generate a stream of fuel droplets directed from an outlet of the fuel droplet generator towards a plasma formation location. In order to prevent droplet satellites from interfering with plasma formation, a gas supply is provided that in use provides a flow of gas (e.g., hydrogen) that deflects any droplet satellites out of the fuel droplet stream. Additionally, a detection apparatus may be provided as part of a shroud to determine the point at which coalescence of fuel droplets occurs thereby providing an indication of the likelihood of satellite droplets being present in the fuel droplet stream.

Abstract: A source collector apparatus for use in a lithographic apparatus includes a fuel droplet generator configured in use to generate a stream of fuel droplets directed from an outlet of the fuel droplet generator towards a plasma formation location. In order to prevent droplet satellites from interfering with plasma formation, a gas supply is provided that in use provides a flow of gas (e.g., hydrogen) that deflects any droplet satellites out of the fuel droplet stream. Additionally, a detection apparatus may be provided as part of a shroud to determine the point at which coalescence of fuel droplets occurs thereby providing an indication of the likelihood of satellite droplets being present in the fuel droplet stream.

Abstract: A source collector apparatus for use in a lithographic apparatus includes a fuel droplet generator configured in use to generate a stream of fuel droplets directed from an outlet of the fuel droplet generator towards a plasma formation location. In order to prevent droplet satellites from interfering with plasma formation, a gas supply is provided that in use provides a flow of gas (e.g., hydrogen) that deflects any droplet satellites out of the fuel droplet stream. Additionally, a detection apparatus may be provided as part of a shroud to determine the point at which coalescence of fuel droplets occurs thereby providing an indication of the likelihood of satellite droplets being present in the fuel droplet stream.

Abstract: A droplet generator, for an EUV radiation source, comprises: a capillary in which, in use, molten material flows; an actuator configured to modulate a pressure inside the capillary; and a controller configured to drive the actuator at a driving frequency; wherein the droplet generator is arranged such that, in use, the driving frequency is equal or about equal to a main resonance frequency of the molten material in the capillary.

Abstract: The present invention provides methods and apparatus for facilitating the start up of a fuel droplet stream generator. During a start-up phase the fuel droplet stream generator is positioned so that the fuel droplets re emitted downwardly whereby gravity assists in the establishment of the stream. The droplets are monitored using a visualization system and once the stream is determined to have the desired characteristics the stream generator is moved to a second position of steady state use in which the droplet stream is emitted in a horizontal direction.

Abstract: A source collector apparatus for use in a lithographic apparatus includes a fuel droplet generator configured in use to generate a stream of fuel droplets directed from an outlet of the fuel droplet generator towards a plasma formation location. In order to prevent droplet satellites from interfering with plasma formation, a gas supply is provided that in use provides a flow of gas (e.g., hydrogen) that deflects any droplet satellites out of the fuel droplet stream. Additionally, a detection apparatus may be provided as part of a shroud to determine the point at which coalescence of fuel droplets occurs thereby providing an indication of the likelihood of satellite droplets being present in the fuel droplet stream.

Abstract: A droplet generator, for an EUV radiation source, comprises: a capillary in which, in use, molten material flows; an actuator configured to modulate a pressure inside the capillary; and a controller configured to drive the actuator at a driving frequency; wherein the droplet generator is arranged such that, in use, the driving frequency is equal or about equal to a main resonance frequency of the molten material in the capillary.

Abstract: A radiation source for generating EUV from a stream of molten metal fuel droplets by LPP (Laser Produced Plasma) or (Dual Laser Plasma) has a fuel droplet generator arranged to provide a stream of droplets of fuel and at least one laser configured to vaporise at least some of said droplets of fuel, whereby radiation is generated. The fuel droplet generator has nozzle, fuel supply line, and reservoir, with a pumping device arranged to supply a flow of molten metal fuel from the reservoir through the fuel feed line and out of the nozzle as a stream of droplets. The fuel droplet generator has a replaceable filter assembly in the fuel feed line, arranged to filter the molten metal fuel in use, to deter nozzle blockage by solid particulate impurities in the fuel.

Abstract: A radiation source for generating EUV from a stream of molten metal fuel droplets by LPP (Laser Produced Plasma) or (Dual Laser Plasma) has a fuel droplet generator arranged to provide a stream of droplets of fuel and at least one laser configured to vaporise at least some of said droplets of fuel, whereby radiation is generated. The fuel droplet generator has nozzle, fuel supply line, and reservoir, with a pumping device arranged to supply a flow of molten metal fuel from the reservoir through the fuel feed line and out of the nozzle as a stream of droplets. The fuel droplet generator has a replaceable filter assembly in the fuel feed line, arranged to filter the molten metal fuel in use, to deter nozzle blockage by solid particulate impurities in the fuel.

Abstract: An immersion lithographic apparatus is disclosed having comprising a pump and buffer volume configured to remove remaining liquid from a substrate, the pump and the buffer volume configured to generate a vacuum cleaning gas flow near the substrate by gas suction into the buffer volume. In an embodiment, since gas flow is needed only a limited amount of time (ordinarily less than 5%), evacuation may be performed using only a moderately powered vacuum pump. In addition or alternatively, the buffer volume may be used as a backup volume buffer configured to provide gas vacuum suction, e.g., in case of a vacuum supply outage.

Abstract: An immersion lithographic apparatus is disclosed having comprising a pump and buffer volume configured to remove remaining liquid from a substrate, the pump and the buffer volume configured to generate a vacuum cleaning gas flow near the substrate by gas suction into the buffer volume. In an embodiment, since gas flow is needed only a limited amount of time (ordinarily less than 5%), evacuation may be performed using only a moderately powered vacuum pump. In addition or alternatively, the buffer volume may be used as a backup volume buffer configured to provide gas vacuum suction, e.g., in case of a vacuum supply outage.

Abstract: An immersion lithographic apparatus is disclosed having comprising a pump and buffer volume configured to remove remaining liquid from a substrate, the pump and the buffer volume configured to generate a vacuum cleaning gas flow near the substrate by gas suction into the buffer volume. In an embodiment, since gas flow is needed only a limited amount of time (ordinarily less than 5%), evacuation may be performed using only a moderately powered vacuum pump. In addition or alternatively, the buffer volume may be used as a backup volume buffer configured to provide gas vacuum suction, e.g., in case of a vacuum supply outage.

Abstract: An immersion lithographic apparatus is disclosed having comprising a pump and buffer volume configured to remove remaining liquid from a substrate, the pump and the buffer volume configured to generate a vacuum cleaning gas flow near the substrate by gas suction into the buffer volume. In an embodiment, since gas flow is needed only a limited amount of time (ordinarily less than 5%), evacuation may be performed using only a moderately powered vacuum pump. In addition or alternatively, the buffer volume may be used as a backup volume buffer configured to provide gas vacuum suction, e.g., in case of a vacuum supply outage.

Abstract: A lithographic apparatus is disclosed. The apparatus includes an illumination system to provide a beam of radiation, and a support structure for supporting a patterning device. The patterning device serves to impart the beam with a pattern in its cross-section. The apparatus also includes a gas flushing device for flushing a substantially laminar flow of gas across the beam of radiation and/or along a surface of an optical component. The gas flushing device includes a single gas outlet that has an inner rim at a downstream end of the gas outlet. The inner rim defines a total gas outlet area. The gas outlet is provided with a laminator that has an effective area out of which, in use, the substantially laminar flow of gas flows. The laminator effective area includes material that has laminator openings and is at least as large as the total gas outlet area.

Abstract: A lithographic projection apparatus includes a radiation system constructed and arranged to supply a projection beam of radiation, a support structure constructed and arranged to support a patterning structure, the patterning structure constructed and arranged to pattern the projection beam according to a desired pattern, a substrate support constructed and arranged to support a substrate, and a projection system constructed and arranged to project the patterned beam onto a target portion of the substrate. The apparatus further includes a gas flushing system comprising radial gas flow outlets, said gas flushing system being constructed and arranged to generate a radial gas flow through said radial gas flow outlets in an intermediate space defined between said gas flushing system and said substrate, wherein the radial gas flow has a radial velocity directed outwards in said space with a magnitude larger than zero at every location in said space.

Abstract: A lithographic projection apparatus includes a radiation system constructed and arranged to supply a projection beam of radiation, a support structure constructed and arranged to support a patterning structure, the patterning structure constructed and arranged to pattern the projection beam according to a desired pattern, a substrate support constructed and arranged to support a substrate, and a projection system constructed and arranged to project the patterned beam onto a target portion of the substrate. The apparatus further includes a gas flushing system comprising radial gas flow outlets, said gas flushing system being constructed and arranged to generate a radial gas flow through said radial gas flow outlets in an intermediate space defined between said gas flushing system and said substrate, wherein the radial gas flow has a radial velocity directed outwards in said space with a magnitude larger than zero at every location in said space.