An extreme ultraviolet light generation apparatus includes a chamber including a first space and a second space; a first partition wall including a first opening through which extreme ultraviolet light passes; a connection portion connecting the chamber and an external apparatus; a second partition wall including a second opening through which the extreme ultraviolet light passes; a gas supply port which allows a gas to pass therethrough; a first exhaust port which opens to the first space; a second exhaust port which opens to a third space located inside the connection portion; a first sensor arranged in the third space; and a processor calculating a first passage flow rate of a gas passing through the first opening based on a measurement result of the first sensor and adjusting a supply flow rate of the gas to be supplied through the gas supply port based on the first passage flow rate.

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.

An extreme ultraviolet light generation chamber device includes a chamber in which a target substance irradiated with laser is turned into plasma and extreme ultraviolet light is generated, a tank configured to store the target substance, a nozzle having an internal space which communicates with the tank and the chamber, an exhaust device configured to exhaust the chamber, a supply device configured to supply a purge gas to the chamber, a pressure sensor configured to measure a pressure in the chamber, and a processor. Here, the processor causes, before the target substance is melted, the exhaust device to exhaust a gas from the chamber, and after the gas is exhausted, performs supply operation to cause the supply device to supply the purge gas into the chamber and exhaust operation to cause the exhaust device to exhaust the purge gas from the chamber.

A laser-sustained broadband light source is disclosed. The light source may include a gas containment structure for plasma generation. The gas containment structure may include a first portion formed from a first grade of sapphire and a second portion formed from a second grade of sapphire. The first portion is coupled to one or more sections of the second portion of second grade sapphire. The light source may include sapphire-to-sapphire bonding between the first-grade sapphire of the first portion and the second-grade sapphire of the second portion, thereby eliminating metal-to-sapphire brazing and avoiding exposure of metal components to destructive UV and/or VUV light. The light source may include a primary laser pump source configured to direct a primary pump beam into the gas containment structure to sustain a plasma and a light collector element configured to collect broadband light emitted from the plasma.

A method for monitoring a laser optical unit of a laser system includes guiding a laser beam through the laser optical unit, performing a first measurement of vibrations arising in the laser optical unit, structure-borne sound arising in the laser optical unit, and/or sound arising in the laser optical unit by using a sensor, and generating an output of the first measurement, and/or an output of a change of the vibrations, of the structure-borne sound, and/or of the sound.

A chamber to generate extreme ultraviolet light includes a gas supply port through which gas is supplied into the chamber; a light concentrating mirror concentrating the extreme ultraviolet light; a first exhaust pipe arranged in the chamber, surrounding a plasma generation region, and including a first opening through which the gas supplied into the chamber is sucked and through which the extreme ultraviolet light is radiated toward the light concentrating mirror, and a first exhaust port through which the gas sucked through the first opening is exhausted to an outside of the chamber; and a second exhaust pipe arranged in the chamber, and including a second opening which is located in a periphery of the first opening and through which the gas supplied into the chamber is sucked, and a second exhaust port through which the gas sucked through the second opening is exhausted to the outside of the chamber.

An extreme ultraviolet light generation apparatus includes a chamber, a target supply unit configured to supply a target into the chamber, a prepulse laser configured to generate a diffusion target having a Gaussian distribution shape convex toward a travel direction of prepulse laser light by irradiating the target with the prepulse laser light, and a main pulse laser configured to generate extreme ultraviolet light by irradiating the diffusion target with main pulse laser light having an intensity distribution of a Gaussian distribution shape.

The present disclosure relates to a photolithography radiation source having an angled primary laser, and an associated method of formation. In some embodiments, the photolithography radiation source has a fuel droplet generator that provides fuel droplets to a source vessel along a first trajectory. A primary laser is configured to generate a primary laser beam along a second trajectory that intersects the first trajectory. The primary laser beam is configured to ignite a plasma from the plurality of fuel droplets that emits radiation. A collector mirror is configured to focus the radiation to an exit aperture of the source vessel. The primary laser beam does not intersect the exit aperture.

The present disclosure relates to an extreme ultraviolet (EUV) radiation source that generates charged tin droplets having a trajectory controlled by an electromagnetic field, and an associated method. In some embodiments, the EUV radiation source has a laser that generates a laser beam. A charged fuel droplet generator provides a plurality of charged fuel droplets having a net electrical charge to an EUV source vessel. An electromagnetic field generator generates an electric field and/or a magnetic field. The net electrical charge of the charged fuel droplets causes the electric or magnetic field to generate a force on the charged fuel droplets that controls a trajectory of the charged fuel droplets to intersect the laser beam. By using the electric or magnetic field to control a trajectory of the charged fuel droplets, the EUV system is able to avoid focus issues between the laser beam and the charged fuel droplets.

A performance recovery method for an EUV light generation system includes performing a first evaluation step of evaluating performance of EUV light while generating the EUV light at a certain repetition frequency during a first period; performing, when an evaluation result of the first evaluation step is not within a normal range, an adjustment step of adjusting the performance and then the first evaluation step as a check step; performing, when an evaluation result of the check step is within the normal range, a second evaluation step of evaluating performance of the EUV light while generating the EUV light at the repetition frequency during a second period longer than the first period; and terminating processing when the evaluation result of the check step is not within the normal range. An index related to an irradiation position of pulse laser light is evaluated in the first and second evaluation steps.