Radiation source and related method

摘要

A radiation source (50) is configured to produce extreme ultraviolet radiation. The radiation source includes a chamber in which, in use, a plasma (P) is generated, and an evaporation surface (62) configured to evaporate a material formed as a by-product (MP) from the plasma and that is emitted to the evaporation surface. A method for removing a by-product material in or from a plasma radiation source of a lithographic apparatus includes evaporating a material which, in use, is emitted to that surface from the plasma.