A collector mirror for an extreme ultraviolet (EUV) light generator includes a first mirror in a vessel, the vessel being configured to receive a material and a laser beam for generating the EUV light, a second mirror surrounding the first mirror, and a detachable third mirror between the first mirror and the second mirror, the third mirror having an inner diameter that is not smaller than an outer diameter of the first mirror, and an outer diameter that is not larger than an inner diameter of the second mirror.

A system for generating extreme ultraviolet light, in which a target material inside a chamber is irradiated with a laser beam to be turned into plasma, includes a first laser apparatus configured to output a first laser beam, a second laser apparatus configured to output a pedestal and a second laser beam, and a controller connected to the first and second laser apparatuses and configured to cause the first laser beam to be outputted first, the pedestal to be outputted after the first laser beam, and the second laser beam having higher energy than the pedestal to be outputted after the pedestal.

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.

An extreme ultraviolet light generation method includes a target supply step of outputting a droplet target into a chamber, a prepulse laser light irradiation step of irradiating the droplet target with prepulse laser light to generate a diffusion target, and a main pulse laser light irradiation step of irradiating the diffusion target with main pulse laser light to generate extreme ultraviolet light. Here, the main pulse laser light includes first main pulse laser light and second main pulse laser light, and in the main pulse laser light irradiation step, the diffusion target is irradiated with the first main pulse laser light having higher energy density at a central portion than at an outer peripheral portion and the second main pulse laser light having higher energy density at the outer peripheral portion than at the central portion.

An extreme ultraviolet light generation apparatus that generates plasma by irradiating a target substance with a pulse laser beam and generates extreme ultraviolet light from the plasma includes: a chamber housing a collector mirror configured to condense the extreme ultraviolet light; a gas introduction pipe through which gas is introduced into the chamber; a mass flow controller configured to change the flow rate of the gas; a discharge pump configured to discharge the gas from the chamber; a pressure sensor configured to monitor the pressure in the chamber; and a control unit configured to control the mass flow controller based on the pressure measured by using the pressure sensor. The control unit controls the mass flow controller to increase an increase ratio of the flow rate of the gas entering the chamber as the pressure acquired by the pressure sensor increases.

A droplet catcher system of an EUV lithography apparatus is provided. The droplet catcher system includes a catcher body, a heat transfer part, a heat exchanger, and a controller. The catcher body has an outer surface. The heat transfer part is directly attached to the outer surface of the catcher body. The heat exchanger is thermally coupled to the heat transfer part. The controller is electrically coupled to the heat exchanger.

A target debris collection device for extreme ultraviolet (EUV) light source apparatus, includes a baffle body extending within an EUV vessel between a collector and an outlet port of the EUV vessel to allow EUV light reflected from the collector to pass through an internal transmissive region thereof, a discharge plate provided in a first end portion of the baffle body adjacent to the collector to collect the target material debris on an inner surface of the baffle body, a guide structure to guide the target material debris collected in the discharge plate to a collection tank, and a first heating member provided in the guide structure to prevent the target material debris from being solidified.

An extreme-ultraviolet light source device comprises: a discharge chamber of which the inside is maintained in a vacuum; an electron beam-emitting unit which is located inside the discharge chamber and produces electron beams; and a metal radiator which is located inside the discharge chamber and is ionized by the electron beams. Extreme-ultraviolet radiation occurs in plasma generated from the metal radiator. The electron beam-emitting unit comprises: a cathode electrode; a plurality of emitters located on the cathode electrode and including a carbon-based material; and a gate electrode which is located on the plurality of emitters at a distance therefrom and to which a pulse voltage is applied.

A light source is provided capable of maintaining the temperature of a collector surface at or below a predetermined temperature. The light source in accordance with various embodiments of the present disclosure includes a processor, a droplet generator for generating a droplet to create extreme ultraviolet light, a collector for reflecting the extreme ultraviolet light into an intermediate focus point, a light generator for generating pre-pulse light and main pulse light, and a thermal image capture device for capturing a thermal image from a reflective surface of the collector.

An extreme ultra violet (EUV) light source apparatus includes a metal droplet generator, a collector mirror, an excitation laser inlet port for receiving an excitation laser, a first mirror configured to reflect the excitation laser that passes through a zone of excitation, and a second mirror configured to reflect the excitation laser reflected by the first mirror.