The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 21, 2009
Filed:
Dec. 26, 2003
Keiji Nagai, Suita, JP;
Hiroaki Nishimura, Suita, JP;
Takayoshi Norimatsu, Suita, JP;
Katsunobu Nishihara, Suita, JP;
Noriaki Miyanaga, Suita, JP;
Masahiro Nakatsuka, Suita, JP;
Yasukazu Izawa, Suita, JP;
Tatsuhiko Yamanaka, Suita, JP;
Mitsuo Nakai, Suita, JP;
Keisuke Shigemori, Suita, JP;
Masakatsu Murakami, Suita, JP;
Yoshinori Shimada, Osaka, JP;
Shigeaki Uchida, Osaka, JP;
Hiroyuki Furukawa, Osaka, JP;
Atsushi Sunahara, Osaka, JP;
Vasilli Zhakhovski, Osaka, JP;
Ryouji Matsui, Suita, JP;
Takahiro Hibino, Suita, JP;
Tomoharu Okuno, Suita, JP;
Keiji Nagai, Suita, JP;
Hiroaki Nishimura, Suita, JP;
Takayoshi Norimatsu, Suita, JP;
Katsunobu Nishihara, Suita, JP;
Noriaki Miyanaga, Suita, JP;
Masahiro Nakatsuka, Suita, JP;
Yasukazu Izawa, Suita, JP;
Tatsuhiko Yamanaka, Suita, JP;
Mitsuo Nakai, Suita, JP;
Keisuke Shigemori, Suita, JP;
Masakatsu Murakami, Suita, JP;
Yoshinori Shimada, Osaka, JP;
Shigeaki Uchida, Osaka, JP;
Hiroyuki Furukawa, Osaka, JP;
Atsushi Sunahara, Osaka, JP;
Vasilli Zhakhovski, Osaka, JP;
Ryouji Matsui, Suita, JP;
Takahiro Hibino, Suita, JP;
Tomoharu Okuno, Suita, JP;
Osaka University, Osaka, JP;
Abstract
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 SnOtarget 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.