Patent ID: 7955767

Claim:
A method for examining at least one wafer with regard to a contamination limit, comprising: examining a contamination potential of a resist of the wafer, which resist outgasses contaminating substances, in an examining location; removing the wafer from the examining location directly to an exposure location if the contamination potential is less than the contamination limit; and exposing the wafer at the exposure location in a projection exposure system that operates in an extreme ultraviolet wavelength range; wherein the examining comprises: arranging the wafer in a vacuum chamber comprising the examining location, evacuating the vacuum chamber, and measuring the contamination potential of the contaminating substances outgassed from the resist in the evacuated vacuum chamber, and wherein, during the measuring of the contamination potential, the resist is at least one of: irradiated with extreme ultraviolet wavelength radiation and bombarded with particles, in a region of the resist not included in the exposing of the wafer.