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 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 method of manufacturing a nozzle for a droplet generator for a laser-produced plasma radiation source is disclosed. The method comprises disposing a glass capillary in a throughbore of a metal fitting, heating the metal fitting; and applying a pressure to the glass capillary such that the glass capillary conforms to the shape of, and forms a direct glass-to-metal seal with, the throughbore. Also disclosed is a nozzle for a droplet generator for a laser-produced plasma radiation source, and the radiation source itself, wherein the nozzle comprises the glass capillary for emitting fuel as droplets and the metal fitting for coupling the glass capillary to a body of the droplet generator, the glass capillary being conformed to a shape of a throughbore of the metal fitting, and wherein the glass capillary forms a direct glass-to-metal seal with the throughbore.

Some implementations herein include a detection circuit and a fast and accurate in-line method for detecting blockage on a droplet generator head of an extreme ultraviolet exposure tool without impacting the flow of droplets of a target material through the droplet generator head. In some implementations described herein, the detection circuit includes a switch circuit that is configured in an open configuration, in which the switch is electrically open between two electrode elements. When an accumulation of the target material occurs across two or more electrode elements on the droplet generator head, the accumulation functions as a switch that closes the detection circuit. A controller may detect closure of the detection circuit.

A coupling arrangement including a first fitting, a second fitting, and a rotational coupler which when turned presses the first fitting against the second fitting, in which the fittings engage rotationally to inhibit relative rotation of the fittings. For example, one of the fittings may have protrusions and the other fitting may have recesses arranged to receive the protrusions.

Apparatus for and method of controlling formation of droplets used to generate EUV radiation. The droplet source includes a fluid exiting an nozzle and a sub-system having an electro-actuatable element producing a disturbance in the fluid. The droplet source produces a stream that breaks down into droplets that in turn coalesce into larger droplets as they progress towards the irradiation region. The electro-actuatable element is driven by a control signal having a sine wave component and a square wave component. Various parameters such as a phase difference between the sine wave component and the square wave component are measured and controlled to minimize the formation of noncoalesced satellite droplets in the stream.

An extreme ultraviolet (EUV) light concentrating apparatus including a main body having a concave inner portion and configured to rotate, a tin generator configured to generate tin drops and spray the tin drops, a tin catcher configured to process the sprayed tin drops, a protective cover configured to block the tin drops from falling into the main body, and a rotation guide configured to rotate the main body may be provided.

A control system includes a plurality of pressure sensors, each to detect a pressure in a respective dynamic gas lock (DGL) nozzle control region of a plurality of DGL nozzle control regions. Each DGL nozzle control region includes one or more DGL nozzles. The control system includes a plurality of mass flow controllers (MFCs). Each MFC of the plurality of MFCs is to control a flow velocity in a respective DGL nozzle control region of the plurality of DGL nozzle control regions. The control system includes a controller to selectively cause one or more MFCs of the plurality of MFCs to adjust flow velocities in one or more DGL nozzle control regions of the plurality of DGL nozzle control regions based on pressures detected by the plurality of pressure sensors in DGL nozzle control regions of the plurality of DGL nozzle control regions.

Some implementations described herein provide techniques and apparatuses for an extreme ultraviolet (EUV) radiation source that includes a backsplash-prevention system to reduce, minimize, and/or prevent the formation of tin (Sn) build-up in a tunnel structure of a collector flow ring that might otherwise be caused by the accumulation of Sn satellites. This reduces backsplash of Sn onto a collector of the EUV radiation source, increases the operational life of the collector (e.g., by increasing the time duration between cleaning and/or replacement of the collector), reduces downtime of the EUV radiation source, and/or enables the performance of the EUV radiation source to be sustained for longer time durations (e.g., by reducing, minimizing, and/or preventing the rate of Sn contamination of the collector), among other examples.