Patent ID: 7755070
Filing Date: 2010-07-13
Classification: B82Y,G03F,G21K,H05G

Abstract:
1. An arrangement for the suppression of unwanted spectral components in an EUV radiation source based on a plasma comprising: vacuum chambers being provided for plasma generation and for the transmission of the emitted radiation to an application, wherein high-vacuum conditions are implemented for low-absorption transmission of the EUV radiation to an application location; a spectral filter unit being provided between the plasma and an application location of the EUV radiation; said filter unit having at least one rapidly flowing gas curtain comprising gases whose atoms or molecules have no absorption maxima for the desired EUV radiation between 13 nm and 14 nm but have different complementing intensive absorption maxima for other, unwanted wavelengths that are emitted, at least in the IR region; and for the purpose of generating the gas curtain, at least one slit nozzle and an efficient gas sink being arranged laterally opposite one another with respect to an optical axis of a beam bundle, which can be coupled out from the plasma, in order to limit the gas curtain in a spatially defined manner and to remove it again from the vacuum chambers as completely as possible.