An apparatus for reducing hydrogen permeation of a mask is provided when generating extreme ultraviolet (EUV) radiation. The apparatus includes a mask stage configured to hold the mask, a hydrogen dispensing nozzle configured to eject hydrogen below the mask, and a trajectory correcting assembly. The trajectory correcting assembly includes a correcting nozzle and a gas flow detector. The correcting nozzle is configured to dispense at least one flow adjusting gas to adjust a trajectory of the hydrogen away from the mask to reduce hydrogen permeation at an edge of the mask. The gas flow detector is configured to measure a variation of an airflow of the hydrogen adjusted by the at least one flow adjusting gas.

A wafer table inspection tool described herein is capable of being positioned over a wafer table while the wafer table is positioned in a bottom module of an exposure tool of a lithography system. The wafer table inspection tool is capable of quickly evaluating the condition of surface burls on the wafer table and evaluating cleaning performance of a cleaning operation in which the surface burls are cleaned.

Some implementations described herein provide techniques and apparatuses for inspecting interior surfaces of a vessel of a radiation source for an accumulation of a target material. An inspection tool, including a laser-scanning system and a motor system supported by an elongated supported member, may be inserted into the vessel to generate an accurate three-dimensional profile of the interior surfaces. Use of the inspection tool is efficient, with short setup and scan times that substantially reduce a duration associated with evaluating the interior surfaces of the vessel for the accumulation.

A method of operating a manufacturing platform includes moving a substrate through the manufacturing platform using one or more transfer modules. A dry resist is deposited on the substrate using a resist deposition module of the manufacturing platform. The substrate is examined for distortion with a metrology system that is part of a transfer module. The dry resist is exposed to UV or EUV radiation using an exposure tool of the manufacturing platform. Exposed or unexposed portions of the dry resist are removed using an etch module of the manufacturing platform.

A plurality of hydrogen outlets are arrayed along a direction normal to a surface (such as a surface of a collector) of an extreme ultraviolet lithography (EUV) tool to increase a volume of hydrogen gas surrounding the surface. As a result, airborne tin is more likely to be stopped by the hydrogen gas surrounding the surface and less likely to bind to the surface. Fewer tin deposits results in increased lifetime for the surface, which reduces downtime for the EUV tool. Additionally, a control device may receive (e.g., from a camera and/or another type of sensor) an indication of levels of tin contamination on the surface and control flow rates to adjust a thickness of the hydrogen curtain. As a result, tin contamination on the collector is less likely to occur and will be more efficiently cleaned by the hydrogen gas, which results in increased lifetime for the surface and reduced downtime for the EUV tool.

Extreme ultraviolet (EUV) lithography systems are provided. A EUV scanner is configured to perform a lithography exposure process in response to EUV radiation. A light source is configured to provide the EUV radiation to the EUV scanner. A measuring device is configured to measure concentration of debris caused by unstable target droplets in the chamber. A controller is configured to adjust a first gas flow rate and a second gas flow rate in response to the measured concentration of the debris and a control signal from the EUV scanner. A exhaust device is configured to extract the debris out of the chamber according to the first gas flow rate. A gas supply device is configured to provide a gas into the chamber according to the second gas flow rate. The control signal indicates the lithography exposure process is completed.

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 radiation source for an EUV lithography apparatus is disclosed. The radiation source comprises a chamber comprising a plasma formation region, a radiation collector arranged in the chamber and configured to collect radiation emitted at the plasma formation region and to direct the collected radiation towards an intermediate focus region, and a radiation conduit disposed between the radiation collector and the intermediate focus region. The radiation conduit comprises at least one outlet on an inner surface of a wall of the radiation conduit for directing a protective gas flow, and at least one guide portion extending from the inner surface of the wall of the radiation conduit and configured to redirect the protective gas flow. Also disclosed is a method of reducing debris and/or vapor deposition in the radiation conduit by providing a protective gas flow to the at least one outlet of the radiation conduit.

A high harmonic radiation source and associated method of generating high harmonic radiation is disclosed. The high harmonic radiation source is configured to condition a gas medium by irradiating the gas medium with a pre-pulse of radiation, thereby generating a plasma comprising a pre-pulse plasma distribution; and irradiate the gas medium with a main pulse of radiation to generate said high harmonic radiation. The conditioning step is such that the plasma comprising a pre-pulse plasma distribution acts to configure a wavefront of said main pulse to improve one or both of: the efficiency of the high harmonic generation process and the beam quality of the high harmonic radiation. The high harmonic radiation source further may comprise a beam shaping device configured to shape said customized pre-pulse prior to said conditioning.

A method of making a mirror for use with extreme ultraviolet (EUV) or X-ray radiation is disclosed. The method includes: a) providing an optical element having a curved mirror surface, wherein the curved mirror surface comprises localized defects that degrade performance of the curved mirror surface; b) spin-coating the curved mirror surface with a material to cover at least some of the defects; and c) curing the spin-coated material on the curved mirror surface to reduce the number of defects and improve the performance of the curved mirror surface. Also disclosed is a mirror made by the method.