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 laser apparatus according to the present disclosure includes an excitation light source configured to output excitation light, a laser crystal disposed on an optical path of the excitation light, a first monitor device disposed on an optical path of transmitted excitation light after having transmitted through the laser crystal to monitor the transmitted excitation light, a temperature adjustment device configured to adjust a temperature of the excitation light source to a constant temperature based on a temperature command value, and a controller configured to change the temperature command value based on a result of monitoring by the first monitor device.

An illumination source includes a laser driver unit configured to emit a plasma sustaining beam. An ingress collimator receives the plasma sustaining beam and produces a collimated ingress beam. A focusing optic receives the collimated ingress beam and produce a focused sustaining beam. A sealed lamp chamber contains an ionizable media that, once ignited, forms a high intensity light emitting plasma having a waist size smaller than 150 microns. The sealed lamp chamber further includes an ingress window configured to receive the focused sustaining beam and an egress window configured to emit the high intensity light. An ignition source is configured to ignite the ionizable media, and an exit fiber is configured to receive and convey the high intensity light. The high intensity light is white light with a black body spectrum, and the exit fiber has a diameter in the range of 200-500 micrometers.

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 method includes ejecting a metal droplet from a reservoir of a first droplet generator assembled to a vessel; emitting an excitation laser from a laser source to the metal droplet to generate extreme ultraviolet (EUV) radiation; turning off the first droplet generator; cooling down the first droplet generator to a temperature not lower than about 150° C.; dismantling the first droplet generator from the vessel at the temperature not lower than about 150° C.; and assembling a second droplet generator to the vessel.

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.

Methods and systems for characterizing dimensions and material properties of semiconductor devices by transmission small angle x-ray scatterometry (TSAXS) systems having relatively small tool footprint are described herein. The methods and systems described herein enable Q space resolution adequate for metrology of semiconductor structures with reduced optical path length. In general, the x-ray beam is focused closer to the wafer surface for relatively small targets and closer to the detector for relatively large targets. In some embodiments, a high resolution detector with small point spread function (PSF) is employed to mitigate detector PSF limits on achievable Q resolution. In some embodiments, the detector locates an incident photon with sub-pixel accuracy by determining the centroid of a cloud of electrons stimulated by the photon conversion event. In some embodiments, the detector resolves one or more x-ray photon energies in addition to location of incidence.

Laser plasma optical device comprising a laser system for outputting driving light pulses and signal light pulses, a vacuum target chamber, a gas target generating device for generating gas and forming a required plasma channel target through high voltage capillary discharge ionization (or through laser picosecond pre-pulse ablation) of gas, and a focusing element. The driving light pulse is focused on the generated plasma channel target through the focusing element to generate a density-modulated plasma wake; and after a predetermined delay time T, the signal light pulse is focused onto a leading edge region of a second plasma density cavitation bubble of the plasma wake through the focusing element, so that the frequency of the signal light pulse is red-shifted to generate an ultra-intense near-single-cycle mid-infrared pulse.

An EUV collector mirror for an extreme ultra violet (EUV) radiation source apparatus includes an EUV collector mirror body on which a reflective layer as a reflective surface is disposed, a heater attached to or embedded in the EUV collector mirror body and a drain structure to drain melted metal from the reflective surface of the EUV collector mirror body to a back side of the EUV collector mirror body.