An apparatus for generating x-rays includes an electron beam generator and a first device arranged to apply an RF electric field to accelerate the electron beam from the generator. A photon source is arranged to provide photons to a zone to interact with the electron beam from the first device so as to generate x-rays via inverse-Compton scattering. A second device is arranged to apply an RF electric field to decelerate the electron beam after it has interacted. The first and second devices are connected by RF energy transmission means arranged to recover RF energy from the decelerated electron beam as it passes through the second device and transfer the recovered RF energy into the first device.

An apparatus for generating x-rays includes an electron beam generator and a first device arranged to apply an RF electric field to accelerate the electron beam from the generator. A photon source is arranged to provide photons to a zone to interact with the electron beam from the first device so as to generate x-rays via inverse-Compton scattering. A second device is arranged to apply an RF electric field to decelerate the electron beam after it has interacted. The first and second devices are connected by RF energy transmission means arranged to recover RF energy from the decelerated electron beam as it passes through the second device and transfer the recovered RF energy into the first device.

Provided is an apparatus for and method of controlling formation of droplets (102a, b) used to generate EUV radiation that comprise an arrangement producing a laser beam directed to an irradiation region and a droplet source. The droplet source (92) includes a fluid exiting an nozzle (98) and a sub-system having an electro-actuatable element (104) producing a disturbance in the fluid (96). The droplet source produces a stream (100) that breaks down into droplets that in turn coalesce into larger droplets as they progress towards the irradiation region. The electro-actuatable element is driven by a hybrid waveform that controls the droplet generation/coalescence process. Also disclosed is a method of determining the transfer function for the nozzle.

A method of manufacturing a multi-layer mirror comprising a multi-layer stack of pairs of alternating layers of a first material and silicon, the method comprising depositing a stack of pairs of alternating layers of the first material and layers of silicon, the stack being supported by a substrate and doping at least a first layer of the first material with a dopant material.

The present invention is related to an apparatus for transporting a charged particle beam. The apparatus may include means for scanning the charged particle beam on a target, a dipole magnet arranged upstream of the means for scanning, at least three quadrupole lenses arranged between the dipole magnet and the means for scanning and means for adjusting the field strength of said at least three quadrupole lenses in function of the scanning angle of the charged particle beam. The apparatus can be made at least single achromatic.

The present invention is related to an apparatus for transporting a charged particle beam. The apparatus may include means for scanning the charged particle beam on a target, a dipole magnet arranged upstream of the means for scanning, at least three quadrupole lenses arranged between the dipole magnet and the means for scanning and means for adjusting the field strength of said at least three quadrupole lenses in function of the scanning angle of the charged particle beam. The apparatus can be made at least single achromatic.

Beam guiding devices for guiding a laser beam, in particular in a direction towards a target region for producing extreme ultraviolet (EUV) radiation, include an adjustment device for adjusting a beam diameter and an aperture angle of the laser beam. The adjustment device includes a first mirror having a first curved reflecting surface, a second mirror having a second curved reflecting surface, a third mirror having a third curved reflecting surface, a fourth mirror having a fourth curved reflecting surface, and a movement device configured to adjust the beam diameter and the aperture angle of the laser beam by moving the first reflecting surface and the fourth reflecting surface relative to one another and, independently thereof, moving the second reflecting surface and the third reflecting surface together relative to the first reflecting surface and the fourth reflecting surface.

An method for generating illuminating radiation in an illumination apparatus for use in an inspection apparatus for use in lithographic processes is described. A driving radiation beam is provided that comprises a plurality of radiation pulses. The beam is split into first and second pluralities of driving radiation pulses. Each plurality of driving radiation pulses has a controllable characteristic. The first and second pluralities may be used to generate an illuminating radiation beam with an output wavelength spectrum. The first and second controllable characteristics are controlled so as to control first and second portions respectively of the output wavelength spectrum of the illuminating radiation beam.

An x-ray transmitter, which may be compact, may be in the form of a housing with an x-ray transparent window sputtered with a metal on one wall, and tribocharging electron source on another wall.

An x-ray transmitter, which may be compact, may be in the form of a housing with an x-ray transparent window sputtered with a metal on one wall, and tribocharging electron source on another wall.