An aperture for detecting a laser beam misalignment, the aperture comprising: a body including a first opening and defining a first axis; a beam dump; an optical element including a second opening wherein the first opening and the second opening are coaxial with the first axis, the optical element being configured to redirect a misaligned laser beam to a detector or to split a misaligned laser beam into at least two sub-beams; a laser beam detection system configured to detect laser light, wherein the optical element is configured to direct a first sub-beam to the beam dump, and to direct a second sub-beam to the laser beam detection system. Also described is an aperture including an enclosure, a method of detecting misalignment of a laser beam, a radiation source comprising such an aperture, a lithographic apparatus comprising such a radiation source or aperture, and the use of the same in a lithographic apparatus or method.

A light source apparatus according to the present embodiment includes: a target holding unit including a holding region configured to hold a target material that generates light by excitation light being provided; a rotary shaft configured to support the target holding unit; and an axial rotation drive unit that is connected to the rotary shaft and configured to rotate, the target holding unit around a central axis of the rotary shaft, wherein the target holding unit is rotated by a predetermined target rotational angular velocity, and the target holding unit has a mass such that a critical angular velocity during rotation is equal to or lower than 85% of the target rotational angular velocity.

A target material generator includes a fluid flow path between reservoir system and a nozzle supply system, and a coupling assembly in the fluid flow path. The target material generator is a part of an extreme ultraviolet light source. The coupling assembly includes a first fitting coupled to a second fitting to thereby form a flow conduit along the fluid flow path, wherein a seal is formed between the first fitting and the second fitting, and a sleeve disposed along inner walls of the flow conduit and between the seal and the flow conduit such that a contaminant trap is formed between the sleeve and the seal.

A photolithographic apparatus includes a droplet generator, a droplet generator maintenance system, and a controller communicating with the droplet generator maintenance system. The droplet generator maintenance system operatively communicates with the droplet generator, a coolant distribution unit, a gas supply unit, and a supporting member. The gas supply unit includes a heat exchange assembly and an air heating assembly. The coolant distribution unit is configured to control the temperature of the droplet generator within the acceptable droplet generator range.

The portable radiation generator of the present disclosure includes a radiation source unit that generates radiation, a collimating unit that is positioned in a first direction with respect to the radiation source unit and determines an irradiation range of the radiation radiated onto a surface of a target by limiting the radiation generated by the radiation source unit, a light radiating unit that is positioned in a direction opposite to the first direction with respect to the collimating unit and generates visible light, and a control unit that controls an operation of at least one of the radiation source unit and the light radiating unit, wherein the collimating unit includes a radiating plate of which at least a portion of a surface in the first direction is radiolucent and which includes a light emitting area limiting the visible light to output guide light having a preset shape to the outside.

A photolithographic apparatus includes a droplet generator, a droplet generator maintenance system, and a controller communicating with the droplet generator maintenance system. The droplet generator maintenance system operatively communicates with the droplet generator, a coolant distribution unit, a gas supply unit, and a supporting member. The gas supply unit includes a heat exchange assembly and an air heating assembly. The coolant distribution unit is configured to control the temperature of the droplet generator within the acceptable droplet generator range.

A method for operating a radiation source apparatus is provided. The method includes producing extreme ultraviolet (EUV) radiation by emitting a laser onto a target material in a vessel; directing a gas from the vessel into a first debris handling device; blocking the gas from the first debris handling device; and perform a maintenance process on the first debris handling device when the gas is blocked from the first debris handling device.

In an embodiment, a method includes: heating a byproduct transport ring of an extreme ultraviolet source, the byproduct transport ring disposed beneath vanes of the extreme ultraviolet source; after heating the byproduct transport ring for a first duration, heating the vanes; after heating the vanes, cooling the vanes; and after cooling the vanes for a second duration, cooling the byproduct transport ring.

In an embodiment, a method includes: heating a byproduct transport ring of an extreme ultraviolet source, the byproduct transport ring disposed beneath vanes of the extreme ultraviolet source; after heating the byproduct transport ring for a first duration, heating the vanes; after heating the vanes, cooling the vanes; and after cooling the vanes for a second duration, cooling the byproduct transport ring.

Some implementations described herein incorporate a heating system to heat a cover of a bucket. A liquified target material, collected by vanes and/or a transport ring within a vessel of an extreme ultraviolet (EUV) radiation source, flows through a drain port of the transport ring and through a conduit that provides the liquified target material to the bucket through an opening of the cover. By heating the cover, the heating system prevents the liquified target material from solidifying at or near the opening before the liquified target material can flow into the bucket. By preventing the solidifying of the liquid target material, a likelihood of a blockage within the conduit and/or the drain port is reduced.