Radiation source, lithographic apparatus and device manufacturing method

摘要

A radiation source generates extreme ultraviolet radiation for a lithographic apparatus as a chamber that is provided with a low pressure hydrogen environment. A trace amount of a protective compound, e.g., H2O, H2O2, O2, NH3 or NOx, is provided to the chamber to assist in maintaining a protective oxide film on metal, e.g., titanium, components in the chamber.

主权项

1. A radiation source comprising:
a vacuum chamber enclosing a component comprising a non-inert material and enclosing a radiation generating element comprising a fuel; a gas supply arranged to supply hydrogen to the vacuum chamber; and a protecting device arranged to supply a trace amount of a protective compound to the vacuum chamber, wherein the radiation source is configured to supply a beam of extreme ultraviolet radiation to a lithographic apparatus, and wherein a temperature inside the vacuum chamber, a first partial pressure of the protective compound in the vacuum chamber, and a second partial pressure of hydrogen in the vacuum chamber are such that the protective compound preferentially bonds to the non-inert material rather than hydrogen and are such that the fuel remains in a non-oxidized state inside the vacuum chamber.