A radiation source apparatus includes a vessel, a laser source, a collector, and a reflective mirror. The vessel has an exit aperture. The laser source is at one end of the vessel and configured to excite a target material to form a plasma. The collector is disposed in the vessel and configured to collect a radiation emitted by the plasma and to direct the collected radiation to the exit aperture of the vessel. The reflective mirror is in the vessel and configured to reflect the laser beam toward an edge of the vessel.

An extreme ultraviolet light generation apparatus includes a chamber in which a target is turned into plasma to generate extreme ultraviolet light, a target generator, an illumination device, and an imaging device receiving illumination light and capturing a target image. The imaging device includes a first transfer optical system transferring the target image, a mask having an opening formed at a transfer position of the first transfer optical system, a second transfer optical system transferring the target image at the opening, an image intensifier arranged such that a photoelectric surface is located at a transfer position of the second transfer optical system, a third transfer optical system transferring the target image at a fluorescent surface, an image sensor arranged at a transfer position of the third transfer optical system, and a moving mechanism capable of moving the mask by an amount equal to or larger than the opening.

A laser apparatus according to an aspect of the present disclosure includes: a master oscillator; at least one amplifier disposed on an optical path of a first pulse laser beam output from the master oscillator; a sensor disposed on an optical path of a second pulse laser beam output from the at least one amplifier; and a laser controller. The laser controller causes the laser apparatus to perform burst oscillation based on a burst signal from an external device, and performs processing of controlling a beam parameter based on a sensor output signal obtained from the sensor in a burst duration, and processing of detecting self-oscillation light from the amplifier based on a sensor output signal obtained from the sensor in a burst stop duration.

An EUV light source module includes an EUV vessel, a collector disposed in the EUV vessel, a droplet generator, a droplet catcher, and a droplet collecting system. The droplet generator is coupled to the EUV vessel and configured to provide a plurality of target droplets into the EUV vessel. The droplet catcher is coupled to the EUV vessel and configured to catch at least a target droplet from the EUV vessel. The droplet colleting system is coupled to the droplet catcher. The droplet collecting system includes a connecting port coupled to the droplet catcher, and a thermal insulating device surrounding the droplet catcher. The droplet generator and the droplet catcher are disposed at opposite locations in the EUV vessel.

Some implementations described herein provide techniques and apparatuses for inspecting interior surfaces of a vessel of a radiation source for an accumulation of a target material. An inspection tool, including a laser-scanning system and a motor system supported by an elongated supported member, may be inserted into the vessel to generate an accurate three-dimensional profile of the interior surfaces. Use of the inspection tool is efficient, with short setup and scan times that substantially reduce a duration associated with evaluating the interior surfaces of the vessel for the accumulation.

A laser apparatus according to the present disclosure includes an excitation light source configured to output excitation light, a laser crystal disposed on an optical path of the excitation light, a first monitor device disposed on an optical path of transmitted excitation light after having transmitted through the laser crystal to monitor the transmitted excitation light, a temperature adjustment device configured to adjust a temperature of the excitation light source to a constant temperature based on a temperature command value, and a controller configured to change the temperature command value based on a result of monitoring by the first monitor device.

An illumination source includes a laser driver unit configured to emit a plasma sustaining beam. An ingress collimator receives the plasma sustaining beam and produces a collimated ingress beam. A focusing optic receives the collimated ingress beam and produce a focused sustaining beam. A sealed lamp chamber contains an ionizable media that, once ignited, forms a high intensity light emitting plasma having a waist size smaller than 150 microns. The sealed lamp chamber further includes an ingress window configured to receive the focused sustaining beam and an egress window configured to emit the high intensity light. An ignition source is configured to ignite the ionizable media, and an exit fiber is configured to receive and convey the high intensity light. The high intensity light is white light with a black body spectrum, and the exit fiber has a diameter in the range of 200-500 micrometers.

A system and a method for supplying target material in an EUV light source are provided. The system for supplying a target material comprises a priming assembly, a refill assembly and a droplet generator assembly. The priming is configured to transform the target material from a solid state to a liquid state. The refill assembly is in fluid communication with the priming assembly and configured to receive the target material in the liquid state from the priming assembly. Further, the refill assembly includes a purifier configured to purify the target material in the liquid state. The droplet generator assembly is configured to supply the target material in the liquid state from the refill assembly.

A method includes ejecting a metal droplet from a reservoir of a first droplet generator assembled to a vessel; emitting an excitation laser from a laser source to the metal droplet to generate extreme ultraviolet (EUV) radiation; turning off the first droplet generator; cooling down the first droplet generator to a temperature not lower than about 150° C.; dismantling the first droplet generator from the vessel at the temperature not lower than about 150° C.; and assembling a second droplet generator to the vessel.

A radiation source for an EUV lithography apparatus is disclosed. The radiation source comprises a chamber comprising a plasma formation region, a radiation collector arranged in the chamber and configured to collect radiation emitted at the plasma formation region and to direct the collected radiation towards an intermediate focus region, and a radiation conduit disposed between the radiation collector and the intermediate focus region. The radiation conduit comprises at least one outlet on an inner surface of a wall of the radiation conduit for directing a protective gas flow, and at least one guide portion extending from the inner surface of the wall of the radiation conduit and configured to redirect the protective gas flow. Also disclosed is a method of reducing debris and/or vapor deposition in the radiation conduit by providing a protective gas flow to the at least one outlet of the radiation conduit.