EXTREME ULTRAVIOLET LIGHT SOURCE, EXTREME ULTRAVIOLET LIGHT SOURCE TARGETS AND METHODS OF MANUFACTURING AN EXTREME ULTRAVIOLET LIGHT SOURCE TARGET

• Main Authors: YAMANAKA, TATSUHIKO, MIYANAGA, NORIAKI, NISHIHARA, KATSUNOBU, UCHIDA, SHIGEAKI, SHIGEMORI, KEISUKE, OKUNO, TOMOHARU, NAKAI, MITSUO, SHIMADA, YOSHINORI, ZHAKHOVSKI, VASILLI, NAKATSUKA, MASAHIRO, FURUKAWA, HIROYUKI, MATSUI, RYOUJI, NAGAI, KEIJI, IZAWA, YASUKAZU, MURAKAMI, MASAKATSU, NISHIMURA, HIROAKI, SUNAHARA, ATSUSHI, NORIMATSU, TAKAYOSHI, HIBINO, TAKAHIRO
• Format: Patent
• Language: English; French; German
• Published: 25.09.2013
• Subjects: APPARATUS SPECIALLY ADAPTED THEREFOR; BASIC ELECTRIC ELEMENTS; CINEMATOGRAPHY; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ELECTROGRAPHY; GAMMA RAY OR X-RAY MICROSCOPES; HOLOGRAPHY; IRRADIATION DEVICES; MATERIALS THEREFOR; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; ORIGINALS THEREFOR; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OFNEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMICBEAMS; SEMICONDUCTOR DEVICES; TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOTOTHERWISE PROVIDED FOR; X-RAY TECHNIQUE

An object of the present invention is to provide an extreme ultraviolet light source target which can emits extreme ultraviolet light with high emission efficiency. A solid target made of heavy metal or heavy-metal compound and having a density 0.5 to 80% that of the crystal density is used. When the target is irradiated with a laser beam, plasma of the heavy metal contained in the target is generated, and extreme ultraviolet light having a predetermined wavelength which corresponds to the kind of the heavy metal is emitted from the plasma. When the density of the target is made to be smaller than the crystal density as described above, space distribution of the density of the generated plasma can be controlled, and the region in which plasma absorbs energy of the laser beam overlaps the region in which the plasma emits the extreme ultraviolet light. Thus, emission efficiency can be improved, preventing energy loss. For example, in a case where the SnO 2 target having a density 24% of the crystal density is used, the emission efficiency at around 13.5 nm wavelength is higher than in the case where a Sn crystal target is used.