Lithographic apparatus having a monitoring device for detecting contamination

A lithographic apparatus comprising:

• a projection system configured to project a first radiation beam onto a target portion of a substrate;
• and
• at least one monitoring device configured to detect at least one contamination species in an interior space of the apparatus, said monitoring device comprising
• at least one dummy element having at least one contamination receiving surface, said contamination receiving surface being in contact with said interior space;
• at least one emitter configured to emit a second radiation beam, said second radiation beam being projected at least partially onto the contamination receiving surface of said dummy element;
• and
• a detector constructed and arranged to detect whether the at least one contamination receiving surface of the dummy element has been contaminated,
• wherein said dummy element is at least partially transparent to the radiation of said at least second radiation beam, and
• wherein the at least one dummy element is constructed to provide an array of contamination receiving surfaces, and wherein at least part of said at least second radiation beam passes through all of the contamination receiving surfaces of said array at least once.

A lithographic apparatus comprising:

• a projection system configured to project a first radiation beam onto a target portion of a substrate;
• and
• at least one monitoring device configured to detect at least one contamination species in an interior space of the apparatus, said monitoring device comprising
• at least one dummy element having at least one contamination receiving surface, said contamination receiving surface being in contact with said interior space;
• at least one emitter configured to emit a second radiation beam, said second radiation beam being projected at least partially onto the contamination receiving surface of said dummy element;
• and
• a detector constructed and arranged to detect whether the at least one contamination receiving surface of the dummy element has been contaminated,
• wherein said dummy element is located between at least two radiation reflectors, and wherein the reflectors are arranged to reflect radiation of said second radiation beam towards each other, through said dummy element.

A lithographic apparatus, comprising:

• a projection system configured to project a first radiation beam onto a target portion of a substrate;
• and
• at least one monitoring device configured to detect at least one contamination species in an interior space of the apparatus, said monitoring device comprising
• at least one dummy element having at least one contamination receiving surface, which contamination receiving surface is in contact with said interior space and not exposed to the first radiation beam;
• at least one emitter configured to emit an electron beam or ionizing beam, said electron beam or ionizing beam being projected at least partially onto the contamination receiving surface of said dummy element;
• and
• a detector constructed and arranged to detect whether the at least one contamination receiving surface of the dummy element has been contaminated.

A lithographic apparatus, comprising:

• a plurality of optical elements configured to project a first radiation beam onto a target portion of a substrate;
• at least one radiation source configured to emit a second radiation beam;
• a radiation beam controller configured to direct the second radiation beam onto at least two different locations of at least one of said optical elements;
• and
• at least one detector configured to detect electrical current, which current emanates from said at least two different locations of said optical element when that locations interact with said second radiation beam.