ИСТИНА

The invention provides a method for cleaning an element of a lithographic apparatus using nitrogen radicals according to the claims. It is an aspect of the present invention to provide a method for cleaning an element of a lithographic apparatus, especially for cleaning one or more optical elements of the lithographic apparatus. A lithographic apparatus is disclosed comprising an electrical discharge generator wherein the electrical discharge generator is arranged to provide an electrical discharge. According to another aspect of the invention a method for cleaning one or more elements of a lithographic apparatus is provided, the method comprising providing a gas containing nitrogen; generating nitrogen radicals from at least part of the gas, thereby forming a radical containing gas; providing at least part of the radical containing gas to the one or more elements of the apparatus.