PHOTON SOURCE COMPRISING A PRESSURE GRADIENT ECR SOURCE

摘要

The invention relates to a photon source comprising a plasma source for the generation of multicharged ions at electron cyclotron resonance (ECR), said multicharged ions corresponding to several charge states of a first component (g1) which is introduced into a vacuum chamber (CH), whereby at least one charge state emits photons having wavelength ?_O by means of deexcitation. The invention is characterised in that it also comprises means for establishing a pressure gradient inside the chamber (CH) for the first component (g1) and/or at least one second component (g2) that is different from the first (g1), whereby said pressure gradient can create a gradient in terms of plasma electron energy such that additional multicharged ions are created, which emit photons having a wavelength that is essentially equal to ?_O by means of deexcitation. The invention is suitable for the production of extreme ultraviolet photons which are used in lithography.