Patents by Inventor Akihiko Isao
Akihiko Isao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 7282308Abstract: In the formation of a halftone type phase shift mask, a reactive gas introduction inlet and an inert gas introduction inlet are provided so as to introduce the respective gases separately and by using a reactive low throw sputtering method a molybdenum silicide based phase shifter film is formed. Thereby, it becomes possible to provide a halftone type phase shift mask, which is applicable to an ArF laser or to a KrF laser, by using molybdenum silicide based materials.Type: GrantFiled: June 30, 2006Date of Patent: October 16, 2007Assignees: Ulvac Coating Corporation, Renesas Technology Corp.Inventors: Susumu Kawada, Akihiko Isao, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Publication number: 20070009810Abstract: In the formation of a halftone type phase shift mask, a reactive gas introduction inlet and an inert gas introduction inlet are provided so as to introduce the respective gases separately and by using a reactive low throw sputtering method a molybdenum silicide based phase shifter film is formed. Thereby, it becomes possible to provide a halftone type phase shift mask, which is applicable to an ArF laser or to a KrF laser, by using molybdenum silicide based materials.Type: ApplicationFiled: June 30, 2006Publication date: January 11, 2007Applicants: ULVAC COATING CORPORATION, RENESAS TECHNOLOGY CORP.Inventors: Susumu Kawada, Akihiko Isao, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Patent number: 7090947Abstract: In the formation of a halftone type phase shift mask, a reactive gas introduction inlet and an inert gas introduction inlet are provided so as to introduce the respective gases separately and by using a reactive low throw sputtering method a molybdenum silicide based phase shifter film is formed. Thereby, it becomes possible to provide a halftone type phase shift mask, which is applicable to an ArF laser or to a KrF laser, by using molybdenum silicide based materials.Type: GrantFiled: March 13, 2001Date of Patent: August 15, 2006Assignees: Ulvac Coating Corporation, Renesas Technology Corp.Inventors: Susumu Kawada, Akihiko Isao, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Patent number: 6689515Abstract: A uniform thin phase-shifting photomask blank can be formed by depositing a thin film on a substrate by a reactive sputtering technique while passing, at least four times, the substrate over a sputtering target. In the formation of the blank, NO gas is used as the reactive gas, a target composed of a mixture of molybdenum and silicon is used as the sputtering target and a transparent substrate is used as the thin film-forming substrate to form, on the transparent substrate, a light-transmitting film capable of transmitting light rays having an intensity, which cannot substantially contribute to the exposure. In addition, the film is formed, on the substrate, through an opening having a sufficiently enlarged length along the substrate-conveying direction so that even regions whose deposition rate of the target component is not more than 90% of the maximum level thereof also contribute to the film-formation.Type: GrantFiled: March 15, 2001Date of Patent: February 10, 2004Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Nobuyuki Yoshioka, Akihiko Isao, Susumu Kawada, Tsuneo Yamamoto, Jun Amano, Ryoichi Kobayashi
-
Patent number: 6569577Abstract: A phase-shift photo mask blank comprises a half tone phase-shift film, wherein the half tone phase-shift film consists of at least two layers and in the case of two layers, the refractive index of the upper layer of the film is smaller than that of the lower layer thereof; in the case of three layers, the refractive index of the intermediate layer is smaller than those observed for the upper and lower layers or the refractive index of the upper layer is smaller than that of an intermediate layer; in the case of at least 4 layers, the refractive index of the upper most layer is smaller than that of the layer immediately below the upper most layer. The photo mask blank permits the production of a phase-shift photo mask having a high transmittance at an exposure wavelength and a low reflectance as well as a low transmittance at a defect-inspection wavelength. The photo mask in turn permits the fabrication of a semiconductor device having a fine pattern.Type: GrantFiled: November 3, 2000Date of Patent: May 27, 2003Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Susumu Kawada, Shuichiro Kanai, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Publication number: 20020009653Abstract: In the formation of a halftone type phase shift mask, a reactive gas introduction inlet and an inert gas introduction inlet are provided so as to introduce the respective gases separately and by using a reactive low throw sputtering method a molybdenum silicide based phase shifter film is formed. Thereby, it becomes possible to provide a halftone type phase shift mask, which is applicable to an ArF laser or to a KrF laser, by using molybdenum silicide based materials.Type: ApplicationFiled: March 13, 2001Publication date: January 24, 2002Applicant: ULVAC COATING CORPORATION and MITSUBISHI DENKI KABUSHIKI KAISHAInventors: Susumu Kawada, Akihiko Isao, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Publication number: 20010018154Abstract: A uniform thin phase-shifting photomask blank can be formed by depositing a thin film on a substrate by a reactive sputtering technique while passing, at least four times, the substrate over a sputtering target. In the formation of the blank, NO gas is used as the reactive gas, a target composed of a mixture of molybdenum and silicon is used as the sputtering target and a transparent substrate is used as the thin film-forming substrate to form, on the transparent substrate, a light-transmitting film capable of transmitting light rays having an intensity, which cannot substantially contribute to the exposure. In addition, the film is formed, on the substrate, through an opening having a sufficiently enlarged length along the substrate-conveying direction so that even regions whose deposition rate of the target component is not more than 90% of the maximum level thereof also contribute to the film-formation.Type: ApplicationFiled: March 15, 2001Publication date: August 30, 2001Applicant: Ulvac Coating CorporationInventors: Nobuyuki Yoshioka, Akihiko Isao, Susumu Kawada, Tsuneo Yamamoto, Jun Amano, Ryoichi Kobayashi
-
Patent number: 6228541Abstract: A uniform thin phase-shifting photomask blank can be formed by depositing a thin film on a substrate by a reactive sputtering technique while passing, at least four times, the substrate over a sputtering target. In the formation of the blank, NO gas is used as the reactive gas, a target composed of a mixture of molybdenum and silicon is used as the sputtering target and a transparent substrate is used as the thin film-forming substrate to form, on the transparent substrate, a light-transmitting film capable of transmitting light rays having an intensity, which cannot substantially contribute to the exposure. In addition, the film is formed, on the substrate, through an opening having a sufficiently enlarged length along the substrate-conveying direction so that even regions whose deposition rate of the target component is not more than 90% of the maximum level thereof also contribute to the film-formation.Type: GrantFiled: April 16, 1999Date of Patent: May 8, 2001Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Susumu Kawada, Tsuneo Yamamoto, Jun Amano, Ryoichi Kobayashi, Nobuyuki Yoshioka
-
Patent number: 5952128Abstract: A phase-shifting photomask blank is made by sputtering a target of molybdenum suicide with a sputtering gas to which nitric monoxide is added in a ratio of 2.65-6.47% by volume. A nitrided-oxide film of molybdenum silicide as a phase-shifting film is formed on a transparent substrate. A base phase-shifting film may be formed on a transparent substrate and then a nitrided-oxide film of molybdenum silicide as a surface layer may be formed on top of the base phase-shifting film by sputtering a target of molybdenum silicide with a sputtering gas to which nitric monoxide is added in a ratio of 0.59-6.47% by volume. The transparent substrate on which the nitrided-oxide film of molybdenum slicide is formed may be subjected to a heat treatment at a temperature of 200.degree. C. or more.Type: GrantFiled: April 17, 1996Date of Patent: September 14, 1999Assignees: Ulvac Coating Corporation, Mitsubishi ElectricCompanyInventors: Akihiko Isao, Susumu Kawada, Yoshihiro Saito, Tsuneo Yamamoto, Atsushi Hayashi, Nobuyuki Yoshioka, Akira Chiba, Junji Miyazaki
-
Patent number: 5938897Abstract: A phase-shifting photomask blank is made by sputtering a target of molybdenum silicide with a sputtering gas to which nitric monoxide is added in a ratio of 2.65-6.47% by volume. A nitrided-oxide film of molybdenum silicide as a phase-shifting film is formed on a transparent substrate. A base phase-shifting film may be formed on a transparent substrate and then a nitrided-oxide film of molybdenum silicide as a surface layer may be formed on top of the base phase-shifting film by sputtering a target of molybdenum silicide with a sputtering gas to which nitric monoxide is added in a ratio of 0.59-6.47% by volume. The transparent substrate on which the nitrided-oxide film of molybdenum slicide is formed may be subjected to a heat treatment at a temperature of 200.degree. C. or more.Type: GrantFiled: June 16, 1997Date of Patent: August 17, 1999Assignees: Ulcoat (Ulvac Coating Corporation), Mitsubishi Electric CorporationInventors: Akihiko Isao, Susumu Kawada, Yoshihiro Saito, Tsuneo Yamamoto, Atsushi Hayashi, Nobuyuki Yoshioka, Akira Chiba, Junji Miyazaki
-
Patent number: 5830607Abstract: A second light transmit portion of a phase shift mask is formed of a molybdenum silicide nitride oxide, or a molybdenum silicide oxide, or a chromium nitride oxide, or a chromium oxide, or a chromium carbide nitride oxide film converting a phase of transmitted exposure light by 180.degree. and having the transmittance of at least 2% and less than 5%. In the manufacturing method of the second light transmit portion, a molybdenum silicide nitride oxide film, or a molybdenum silicide oxide film, or a chromium nitride oxide film, or a chromium oxide film, or a carbide nitride oxide film is formed by a sputtering method. Consequently, with a conventional sputtering apparatus, the second light transmit portion can be formed, and additionally, etching process of the phase shifter portion is required only once, so that probabilities of defects and errors in the manufacturing process can be decreased.Type: GrantFiled: May 27, 1997Date of Patent: November 3, 1998Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Ryoichi Kobayashi, Nobuyuki Yoshioka, Yaichiro Watakabe, Junji Miyazaki, Kouichiro Narimatsu, Shigenori Yamashita
-
Patent number: 5691090Abstract: A second light transmit portion of a phase shift mask is formed of a molybdenum silicide nitride oxide or a molybdenum silicide oxide a chromium nitride oxide, or a chromium oxide, or a chromium carbide nitride oxide film converting a phase of transmitted exposure light by 180.degree. and having the transmittance of 5-40%. In the manufacturing method of the second light transmit portion, a molybdenum silicide nitride oxide film or a molybdenum silicide oxide film a chromium nitride oxide film, or a chromium oxide film, or a carbide nitride oxide film is formed by a sputtering method. Consequently, with a conventional sputtering apparatus, the second light transmit portion can be formed, and additionally, etching process of the phase shifter portion is required only once, so that probabilities of defects and errors in the manufacturing process can be decreased.Type: GrantFiled: December 20, 1996Date of Patent: November 25, 1997Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Ryoichi Kobayashi, Nobuyuki Yoshioka, Yaichiro Watakabe, Junji Miyazaki
-
Patent number: 5674647Abstract: A second light transmit portion of a phase shift mask is formed of a molybdenum silicide nitride oxide, or a molybdenum silicide oxide, or a chromium nitride oxide, or a chromium oxide, or a chromium carbide nitride oxide film converting a phase of transmitted exposure light by 180.degree. and having the transmittance of at least 2% and less than 5%. In the manufacturing method of the second light transmit portion, a molybdenum silicide nitride oxide film, or a molybdenum silicide oxide film, or a chromium nitride oxide film, or a chromium oxide film, or a carbide nitride oxide film is formed by a sputtering method. Consequently, with a conventional sputtering apparatus, the second light transmit portion can be formed, and additionally, etching process of the phase shifter portion is required only once, so that probabilities of defects and errors in the manufacturing process can be decreased.Type: GrantFiled: October 24, 1995Date of Patent: October 7, 1997Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Ryoichi Kobayashi, Nobuyuki Yoshioka, Yaichiro Watakabe, Junji Miyazaki, Kouichiro Narimatsu, Shigenori Yamashita
-
Patent number: 5629114Abstract: A second light transmit portion of a phase shift mask is formed of a molybdenum silicide nitride oxide or a molybdenum silicide oxide a chromium nitride oxide, or a chromium oxide, or a chromium carbide nitride oxide film converting a phase of transmitted exposure light by 180.degree. and having the transmittance of 5-40%. In the manufacturing method of the second light transmit portion, a molybdenum silicide nitride oxide film or a molybdenum silicide oxide film a chromium nitride oxide film, or a chromium oxide film, or a carbide nitride oxide film is formed by a sputtering method. Consequently, with a conventional sputtering apparatus, the second light transmit portion can be formed, and additionally, etching process of the phase shifter portion is required only once, so that probabilities of defects and errors in the manufacturing process can be decreased.Type: GrantFiled: June 7, 1995Date of Patent: May 13, 1997Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Ryoichi Kobayashi, Nobuyuki Yoshioka, Yaichiro Watakabe, Junji Miyazaki
-
Patent number: 5605776Abstract: A phase-shifting photomask blank has a transparent substrate, a phase-shifting film deposited on the transparent substrate, the phase-shifting film including a transversely central composition which results in a reduced rate of side etching, and a patterned photoresist film masking the phase-shifting film. When the phase-shifting film is dry-etched through the patterned photoresist film into a desired circuit pattern, transversely different rates of side etching of the phase-shifting film are substantially equalized due to the reduced rate of side etching resulting from the transversely central composition. The circuit pattern includes openings defined by removal of the phase-shifting film and shifters left between the openings. The shifters have respective side surfaces free of steps and extending substantially perpendicularly from the transparent substrate.Type: GrantFiled: August 15, 1995Date of Patent: February 25, 1997Assignees: Ulvac Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Susumu Kawada, Atsushi Hayashi, Nobuyuki Yoshioka, Kazuyuki Maetoko
-
Patent number: 5482799Abstract: A phase shift mask of the present invention includes a quartz substrate transmitting exposure light, a transmitting film having a predetermined transmittance formed on the main surface of quartz substrate, a light transmitting portion from which quartz substrate is exposed is formed in a predetermined region, and a phase shifter portion formed of a single material on light transmitting film converting the phase angle by approximately 180.degree. and having a transmittance of 3-20% with respect to the exposure light transmitted through light transmitting portion. As a result, a defect generated in the phase shifter portion can be easily detected with an ordinary defect inspection apparatus without deteriorating the phase shifter portion as a phase shift mask.Type: GrantFiled: October 5, 1994Date of Patent: January 9, 1996Assignees: Mitsubishi Denki Kabushiki Kaisha, Dainippon Printing Co., Ltd., Ulvac Coating CorporationInventors: Akihiko Isao, Susumu Kawada, Nobuyuki Yoshioka
-
Patent number: 5474864Abstract: A second light transmit portion of a phase shift mask is formed of a molybdenum silicide nitride oxide or a molybdenum silicide oxide a chromium nitride oxide, or a chromium oxide, or a chromium carbide nitride oxide film converting a phase of transmitted exposure light by 180.degree. and having the transmittance of 5-40%. In the manufacturing method of the second light transmit portion, a molybdenum silicide nitride oxide film or a molybdenum silicide oxide film a chromium nitride oxide film, or a chromium oxide film, or a carbide nitride oxide film is formed by a sputtering method. Consequently, with a conventional sputtering apparatus, the second light transmit portion can be formed, and additionally, etching process of the phase shifter portion is required only once, so that probabilities of defects and errors in the manufacturing process can be decreased.Type: GrantFiled: November 22, 1993Date of Patent: December 12, 1995Assignees: ULVAC Coating Corporation, Mitsubishi Denki Kabushiki KaishaInventors: Akihiko Isao, Ryoichi Kobayashi, Nobuyuki Yoshioka, Yaichiro Watakabe, Junji Miyazaki
-
Patent number: 4428980Abstract: An inhomogeneous optical layer is formed on a surface of a substrate in a vacuum coater, in which the substrate is moved along a travelling path having path sections and two substances are evaporated from their respective sources and both of the substances are deposited on a common surface section of the surface. In such an operation, the deposition rate of each of the substances is varied monotoneously along the path in each of the path section in order that, in a layer formed by the deposition on the substrate, the content of each of the substances is varied monotonously in the direction of thickness. If the refractive index of one of the substances is different from that of the other of the substances, the resultant refractive index in the layer is varied monotoneously in the direction of the thickness of the layer.Type: GrantFiled: May 3, 1983Date of Patent: January 31, 1984Assignee: Ulvac Seimaku Kabushiki KaishaInventors: Kazuo Nakamura, Hirotsugu Mizorogi, Akihiko Isao
-
Patent number: 4428979Abstract: An inhomogeneous optical layer is formed on a surface of a substrate in a vacuum coater, in which the substrate is moved along a travelling path having path sections and a substance is evaporated from its source and deposited on the surface while the deposited substance is exposed to gas which is able to react on the substance. In such an operation, the deposition rate of the substance is varied monotonously along the path in each of the path section in order that, in a layer formed by the deposition on the substrate, the content of the substance and that of the reaction product are varied monotonously in the direction of thickness. If the refractive index of the substance is different from that of the reaction product, the resultant refractive index in the layer is varied monotonously in the direction of the thickness of the layer.Type: GrantFiled: May 3, 1983Date of Patent: January 31, 1984Assignee: Ulvac Seimaku Kabushiki KaishaInventors: Kazuo Nakamura, Hirotsugu Mizorogi, Akihiko Isao
-
Patent number: 4416216Abstract: An inhomogeneous optical layer is formed on a surface of a substrate in a vacuum coater, in which the substrate is moved along a travelling path having path sections and a substance is evaporated from its source and deposited on the surface while the deposited substance is exposed to gas which is able to react on the substance. In such an operation, the deposition rate of the substance is varied monotonously along the path in each of the path section in order that, in a layer formed by the deposition on the substrate, the content of the substance and that of the reaction product are varied monotonously in the direction of thickness. If the refractive index of the substance is different from that of the reaction product, the resultant refractive index in the layer is varied monotonously in the direction of the thickness of the layer.Type: GrantFiled: April 29, 1982Date of Patent: November 22, 1983Assignees: Ulvac Seimaku Kabushiki Kaisha, Nihon Shinku Gijutsu Kabushiki KaishaInventors: Kazuo Nakamura, Hirotsugu Mizorogi, Akihiko Isao