Abstract: A method for generating a radiation light in a lithography exposure system is provided. The method includes connecting a first nozzle assembly coupled to a support to an outlet of a storage member that receives a target fuel inside. The method further includes guiding the target fuel flowing through the first nozzle assembly and supplying a droplet of the target fuel into an excitation zone via the first nozzle assembly. The method also includes moving the support to connect a second nozzle assembly coupled to the support with the outlet. In addition, the method includes guiding the target fuel flowing through the second nozzle assembly and supplying a droplet of the target fuel into the excitation zone via the second nozzle assembly. The method further includes irradiating the droplet of the target fuel in the excitation zone with a laser pulse.

Abstract: A method for generating a radiation light in a lithography exposure system. The method includes producing a predetermined gas pressure in a storage chamber to supply a first load of a target fuel in the storage chamber via a nozzle. The method further includes irradiating the target fuel from the nozzle with a laser to generate the radiation light. The method also includes increasing the gas pressure in a buffer chamber which receives a second load of target fuel to the predetermined gas pressure. In addition, the method includes actuating the flow of the target fuel from the buffer chamber to the storage chamber.

Abstract: The present disclosure provides a method for aligning a master oscillator power amplifier (MOPA) system. The method includes ramping up a pumping power input into a laser amplifier chain of the MOPA system until the pumping power input reaches an operational pumping power input level; adjusting a seed laser power output of a seed laser of the MOPA system until the seed laser power output is at a first level below an operational seed laser power output level; and performing a first optical alignment process to the MOPA system while the pumping power input is at the operational pumping power input level, the seed laser power output is at the first level, and the MOPA system reaches a steady operational thermal state.

Abstract: A method for generating a radiation light in a lithography exposure system is provided. The method includes connecting a first nozzle assembly coupled to a support to an outlet of a storage member that receives a target fuel inside. The method further includes guiding the target fuel flowing through the first nozzle assembly and supplying a droplet of the target fuel into an excitation zone via the first nozzle assembly. The method also includes moving the support to connect a second nozzle assembly coupled to the support with the outlet. In addition, the method includes guiding the target fuel flowing through the second nozzle assembly and supplying a droplet of the target fuel into the excitation zone via the second nozzle assembly. The method further includes irradiating the droplet of the target fuel in the excitation zone with a laser pulse.

Abstract: A target droplet source for an extreme ultraviolet (EUV) source includes a droplet generator configured to generate target droplets of a given material. The droplet generator includes a nozzle configured to supply the target droplets in a space enclosed by a chamber. The target droplet source further includes a sleeve disposed in the chamber distal to the nozzle. The sleeve is configured to provide a path for the target droplets in the chamber.

Abstract: A method of controlling an excitation laser includes detecting, at a droplet generator, a first signal of radiation scattered by a given target droplet irradiated by a first radiation source at a first position. The method of controlling the excitation laser further includes detecting, at the droplet generator, a second signal of radiation scattered by the given target droplet irradiated by a second radiation source at a second position a fixed distance away from the first position, and determining a speed of the given target droplet based on a time lag between the detecting of the first signal and the detecting of the second signal. The method further includes controlling a trigger time for triggering an excitation pulse for heating the given target droplet based on the determined speed of the given target droplet.

Abstract: A droplet generator for an extreme ultraviolet imaging tool includes a reservoir for a molten metal, and a nozzle having a first end connected to the reservoir and a second opposing end where molten metal droplets emerge from the nozzle. A gas inlet is connected to the nozzle, and an isolation valve is at the second end of the nozzle configured to seal the nozzle droplet generator from the ambient.

Abstract: A method for generating a radiation light in a lithography exposure system. The method includes producing a predetermined gas pressure in a storage chamber to supply a first load of a target fuel in the storage chamber via a nozzle. The method further includes irradiating the target fuel from the nozzle with a laser to generate the radiation light. The method also includes increasing the gas pressure in a buffer chamber which receives a second load of target fuel to the predetermined gas pressure. In addition, the method includes actuating the flow of the target fuel from the buffer chamber to the storage chamber.

Abstract: A method for performing a lithographic process over a semiconductor wafer is provided. The method includes coating a photoresist layer over a material layer which is formed on the semiconductor wafer in a track apparatus. The method further includes transferring the semiconductor wafer from the track apparatus to an exposure apparatus. The method also includes measuring a height of the photoresist layer before the removal of the semiconductor wafer from the track apparatus. In addition, the method includes measuring height of the material layer in the exposure apparatus. The method also includes determining a focal length for exposing the semiconductor wafer according to the height of the photoresist layer and the height of the material layer.

Abstract: An apparatus, and a method of using the same, for monitoring and removing tin contamination on windows of an extreme ultraviolet lithography (EUVL) radiation source vessel includes an optical sensing module embedded in one or more monitoring units for inspecting the EUV radiation source. The optical sensing module measures intensity of infrared (IR) radiation. The apparatus further includes heating elements, hydrogen gas supply module, and a gas removal module for removing the tin contamination when the intensity of the IR radiation falls below a threshold of a baseline intensity corresponding to a substantially uncontaminated window.

Abstract: A laser system includes a laser source operable to provide a laser beam; a laser amplifier having an input port and an output port and operable to amplify the laser beam, the laser beam travelling along a main beam path through the laser amplifier from the input port to the output port; and a residual gain monitor operable to provide a probe laser beam, the probe laser beam travelling along a probe beam path through the laser amplifier from the output port to the input port, wherein the residual gain monitor calculates a residual gain of the laser amplifier according to the probe laser beam.