Patents by Inventor Yukishige Saito
Yukishige Saito 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).
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Patent number: 9059402Abstract: A resistance-variable element as disclosed has high reliability, high densification, and good insulating properties. The device provides a resistance-variable element in which a first electrode including a metal primarily containing copper, an oxide film of valve-metal, an ion-conductive layer containing oxygen and a second electrode are laminated in this order.Type: GrantFiled: June 21, 2010Date of Patent: June 16, 2015Assignee: NEC CORPORATIONInventors: Munehiro Tada, Toshitsugu Sakamoto, Yuko Yabe, Yukishige Saito, Hiromitsu Hada
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Patent number: 8946668Abstract: Disclosed is a semiconductor device including a resistive change element between a first wiring and a second wiring, which are arranged in a vertical direction so as to be adjacent to each other, with an interlayer insulation film being interposed on a semiconductor substrate. The resistive change element includes a lower electrode, a resistive change element film made of a metal oxide and an upper electrode. Since the upper electrode on the resistive change element film is formed as part of a plug for the second wiring, a structure in which a side surface of the upper electrode is not in direct contact with the side surface of the metal oxide or the lower electrode is provided so that it is possible to realize excellent device characteristics, even when a byproduct is adhered to the side wall of the metal oxide or the lower electrode in the etching thereof.Type: GrantFiled: January 21, 2011Date of Patent: February 3, 2015Assignee: NEC CorporationInventors: Yukishige Saito, Kimihiko Ito, Hiromitsu Hada
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Patent number: 8766233Abstract: A semiconductor device includes at least first and second electrodes, and a layer including a transition metal oxide layer sandwiched between the first and second electrodes. The transition metal oxide layer includes first and second transition metal oxide layers formed of different first and second transition metals, respectively. The first transition metal oxide layer is provided on the first electrode side, the second transition metal oxide layer is provided on the second electrode side, the first transition metal oxide layer and the second transition metal oxide layer are in contact with each other, the first transition metal oxide layer has an oxygen concentration gradient from the interface between the first transition metal oxide layer and the second transition metal oxide layer toward the first electrode side, and the oxygen concentration at the interface is greater than the oxygen concentration on the first electrode side.Type: GrantFiled: October 4, 2010Date of Patent: July 1, 2014Assignee: NEC CorporationInventors: Yukihiro Sakotsubo, Masayuki Terai, Munehiro Tada, Yuko Yabe, Yukishige Saito
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Publication number: 20120286231Abstract: Disclosed is a semiconductor device including a resistive change element between a first wiring and a second wiring, which are arranged in a vertical direction so as to be adjacent to each other, with an interlayer insulation film being interposed on a semiconductor substrate. The resistive change element includes a lower electrode, a resistive change element film made of a metal oxide and an upper electrode. Since the upper electrode on the resistive change element film is formed as part of a plug for the second wiring, a structure in which a side surface of the upper electrode is not in direct contact with the side surface of the metal oxide or the lower electrode is provided so that it is possible to realize excellent device characteristics, even when a byproduct is adhered to the side wall of the metal oxide or the lower electrode in the etching thereof.Type: ApplicationFiled: January 21, 2011Publication date: November 15, 2012Applicant: NEC CORPORATIONInventors: Yukishige Saito, Kimihiko Ito, Hiromitsu Hada
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Publication number: 20120267598Abstract: A semiconductor device includes at least first and second electrodes, and a layer including a transition metal oxide layer sandwiched between the first and second electrodes. The transition metal oxide layer includes first and second transition metal oxide layers formed of different first and second transition metals, respectively. The first transition metal oxide layer is provided on the first electrode side, the second transition metal oxide layer is provided on the second electrode side, the first transition metal oxide layer and the second transition metal oxide layer are in contact with each other, the first transition metal oxide layer has an oxygen concentration gradient from the interface between the first transition metal oxide layer and the second transition metal oxide layer toward the first electrode side, and the oxygen concentration at the interface is greater than the oxygen concentration on the first electrode side.Type: ApplicationFiled: October 4, 2010Publication date: October 25, 2012Applicant: NEC CORPORATIONInventors: Yukihiro Sakotsubo, Masayuki Terai, Munehiro Tada, Yuko Yabe, Yukishige Saito
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Publication number: 20120091426Abstract: A resistance-variable element as disclosed has high reliability, high densification, and good insulating properties. The device provides a resistance-variable element in which a first electrode including a metal primarily containing copper, an oxide film of valve-metal, an ion-conductive layer containing oxygen and a second electrode are laminated in this order.Type: ApplicationFiled: June 21, 2010Publication date: April 19, 2012Applicant: NEC CORPORATIONInventors: Munehiro Tada, Toshitsugu Sakamoto, Yuko Yabe, Yukishige Saito, Hiromitsu Hada
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Patent number: 7611934Abstract: A semiconductor device includes (a) a semiconductor layer formed on an electrically insulating layer, (b) a gate insulating film formed on the semiconductor layer, (c) a gate electrode formed on the gate insulating film, and (d) a field insulating film formed on the semiconductor layer for defining a region in which a semiconductor device is to be fabricated. The semiconductor layer includes (a1) source and drain regions formed in the semiconductor layer around the gate electrode, the source and drain regions containing first electrically conductive type impurity, (a2) a body contact region formed in the semiconductor layer, the body contact region containing second electrically conductive type impurity, and (a3) a carrier path region formed in the semiconductor layer such that the carrier path region does not make contact with the source and drain regions, but makes contact with the body contact region, the carrier path region containing second electrically conductive type impurity.Type: GrantFiled: July 15, 2005Date of Patent: November 3, 2009Assignee: NEC CorporationInventors: Risho Koh, Yukishige Saito, Jong-Wook Lee, Hisashi Takemura
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Publication number: 20090140322Abstract: A first insulation film (silicon dioxide film) and a second insulation film (aluminum oxide film) are laminated on a surface of a silicon substrate in this order to form a gate insulation film. At least one element (aluminum) of elements, which constitutes the second insulation film but is different from elements commonly contained in the whole area of the first insulation film, is caused to be contained in a part of the first insulation film, whereby a charge trapping site region is formed in the first insulation film.Type: ApplicationFiled: October 3, 2006Publication date: June 4, 2009Inventors: Takashi Nakagawa, Yukishige Saito
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Patent number: 7485923Abstract: A semiconductor device includes a first insulating layer, a semiconductor layer formed on the first insulating layer, a second insulating layer on a part of the semiconductor layer, and a gate electrode formed on the semiconductor layer through the second insulating layer. The semiconductor layer includes a low concentration region formed under the gate electrode through the second insulating layer, two high concentration regions which are formed in at least upper regions on outer sides of the low concentration region under the gate electrode through the second insulating layer, and have an impurity concentration higher than an impurity concentration of the low concentration region, respectively, and two source/drain regions which are formed in side portions of the high concentration regions to have low concentration region side end portions, respectively. A width of the high concentration region is equal to or less than 30 nm.Type: GrantFiled: October 2, 2002Date of Patent: February 3, 2009Assignee: NEC CorporationInventors: Hisashi Takemura, Risho Koh, Yukishige Saito, Jyonu Ri
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Patent number: 7211517Abstract: A method of manufacturing a semiconductor device of the present invention includes (a) sequentially forming a gate insulating film 14, a first conductive layer 15 and a first insulating film 16 on a semiconductor layer 13 provided on an insulating film 12; (b) selectively removing the semiconductor layer, the gate insulating film, the first conductive layer and the first insulating film to form a device isolation trench; (c) forming a second insulating film 17 in the device isolation [element separation] trench, wherein a height of an upper surface of the second insulating film is substantially coincident with that of an upper surface of the first insulating film; (d) removing a part of the second insulating film and the first insulating film such that a height of an upper surface of the exposed first conductive layer is substantially coincident with that of the top surface of the second insulating film; and (e) patterning the first conductive layer to form a gate electrode.Type: GrantFiled: September 5, 2002Date of Patent: May 1, 2007Assignee: NEC CorporationInventors: Yukishige Saito, Risho Koh, Jyonu Ri, Hisashi Takemura
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Patent number: 6975001Abstract: A semiconductor device includes (a) a semiconductor layer formed on an electrically insulating layer, (b) a gate insulating film formed on the semiconductor layer, (c) a gate electrode formed on the gate insulating film, and (d) a field insulating film formed on the semiconductor layer for defining a region in which a semiconductor device is to be fabricated. The semiconductor layer includes (a1) source and drain regions formed in the semiconductor layer around the gate electrode, the source and drain regions containing first electrically conductive type impurity, (a2) a body contact region formed in the semiconductor layer, the body contact region containing second electrically conductive type impurity, and (a3) a carrier path region formed in the semiconductor layer such that the carrier path region does not make contact with the source and drain regions, but makes contact with the body contact region, the carrier path region containing second electrically conductive type impurity.Type: GrantFiled: June 6, 2002Date of Patent: December 13, 2005Assignee: NEC CorporationInventors: Risho Koh, Yukishige Saito, Jong-Wook Lee, Hisashi Takemura
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Publication number: 20050250317Abstract: A semiconductor device includes (a) a semiconductor layer formed on an electrically insulating layer, (b) a gate insulating film formed on the semiconductor layer, (c) a gate electrode formed on the gate insulating film, and (d) a field insulating film formed on the semiconductor layer for defining a region in which a semiconductor device is to be fabricated. The semiconductor layer includes (a1) source and drain regions formed in the semiconductor layer around the gate electrode, the source and drain regions containing first electrically conductive type impurity, (a2) a body contact region formed in the semiconductor layer, the body contact region containing second electrically conductive type impurity, and (a3) a carrier path region formed in the semiconductor layer such that the carrier path region does not make contact with the source and drain regions, but makes contact with the body contact region, the carrier path region containing second electrically conductive type impurity.Type: ApplicationFiled: July 15, 2005Publication date: November 10, 2005Inventors: Risho Koh, Yukishige Saito, Jong-Wook Lee, Hisashi Takemura
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Patent number: 6933569Abstract: A semiconductor device includes a semiconductor layer formed on an insulator, a gate insulating film formed on the semiconductor layer, a gate electrode formed on the gate insulating film and extending in a first direction, source/drain regions formed in the semiconductor layer on both sides of the gate electrode, a body contact region in the semiconductor layer, a partial isolating region in which a field insulating film thicker than the gate insulating film intervenes between the semiconductor layer and an extending portion of the gate electrode, and a full isolating region in which the semiconductor layer on the insulator is removed. The full isolating region is formed to be in contact with at least a part of a side parallel to the first direction of the source/drain regions.Type: GrantFiled: September 24, 2003Date of Patent: August 23, 2005Assignee: NEC CorporationInventors: Risho Koh, Shigeharu Yamagami, Jong-wook Lee, Hitoshi Wakabayashi, Yukishige Saito, Atsushi Ogura, Mitsuru Narihiro, Kohichi Arai, Hisashi Takemura, Tohru Mogami, Toyoji Yamamoto, Yukinori Ochiai
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Publication number: 20050151172Abstract: A semiconductor device includes a first insulating layer, a semiconductor layer formed on the first insulating layer, a second insulating layer on a part of the semiconductor layer, and a gate electrode formed on the semiconductor layer through the second insulating layer. The semiconductor layer includes a low concentration region formed under the gate electrode through the second insulating layer, two high concentration regions which are formed in at least upper regions on outer sides of the low concentration region under the gate electrode through the second insulating layer, and have an impurity concentration higher than an impurity concentration of the low concentration region, respectively, and two source/drain regions which are formed in side portions of the high concentration regions to have low concentration region side end portions, respectively. A width of the high concentration region is equal to or less than 30 nm.Type: ApplicationFiled: October 2, 2002Publication date: July 14, 2005Inventors: Hisashi Takemura, Risho Koh, Yukishige Saito, Jyonu Ri
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Patent number: 6916695Abstract: One object of the present invention is to suppress a threshold voltage of at least an n-channel MISFET using a nitride of a high melting point metal at it's gate electrode. In order to achieve the object, a gate electrode 109 of a p-channel MISFET is constituted of a titanium nitride film 106 and a tungsten film 107 formed on the film 106 and a gate electrode 110a of an n-channel MISFET is constituted of a titanium nitride film 106a and a tungsten film 107 formed on the film 106a. The titanium nitride film 106a is formed by nitrogen ion implantation in the titanium nitride film 106 to decrease the work function.Type: GrantFiled: July 3, 2002Date of Patent: July 12, 2005Assignee: NEC CorporationInventors: Hitoshi Wakabayashi, Yukishige Saito
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Publication number: 20040209438Abstract: A method of manufacturing a semiconductor device of the present invention includes (a) sequentially forming a gate insulating film 14, a first conductive layer 15 and a first insulating film 16 on a semiconductor layer 13 provided on an insulating film 12; (b) selectively removing the semiconductor layer, the gate insulating film, the first conductive layer and the first insulating film to form a device isolation trench; (c) forming a second insulating film 17 in the device isolation [element separation] trench, wherein a height of an upper surface of the second insulating film is substantially coincident with that of an upper surface of the first insulating film; (d) removing a part of the second insulating film and the first insulating film such that a height of an upper surface of the exposed first conductive layer is substantially coincident with that of the top surface of the second insulating film; and (e) patterning the first conductive layer to form a gate electrode.Type: ApplicationFiled: May 11, 2004Publication date: October 21, 2004Inventors: Yukishige Saito, Risho Koh, Jyonu Ri, Hisashi Takemura
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Publication number: 20040129975Abstract: A semiconductor device includes a semiconductor layer formed on an insulator, a gate insulating film formed on the semiconductor layer, a gate electrode formed on the gate insulating film and extending in a first direction, source/drain regions formed in the semiconductor layer on both sides of the gate electrode, a body contact region in the semiconductor layer, a partial isolating region in which a field insulating film thicker than the gate insulating film intervenes between the semiconductor layer and an extending portion of the gate electrode, and a full isolating region in which the semiconductor layer on the insulator is removed. The full isolating region is formed to be in contact with at least a part of a side parallel to the first direction of the source/drain regions.Type: ApplicationFiled: September 24, 2003Publication date: July 8, 2004Applicant: NEC CORPORATIONInventors: Risho Koh, Shigeharu Yamagami, Jong-wook Lee, Hitoshi Wakabayashi, Yukishige Saito, Atsushi Ogura, Mitsuru Narihiro, Kohichi Arai, Hisashi Takemura, Tohru Mogami, Toyoji Yamamoto, Yukinori Ochiai
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Publication number: 20020185687Abstract: A semiconductor device includes (a) a semiconductor layer formed on an electrically insulating layer, (b) a gate insulating film formed on the semiconductor layer, (c) a gate electrode formed on the gate insulating film, and (d) a field insulating film formed on the semiconductor layer for defining a region in which a semiconductor device is to be fabricated. The semiconductor layer includes (a1) source and drain regions formed in the semiconductor layer around the gate electrode, the source and drain regions containing first electrically conductive type impurity, (a2) a body contact region formed in the semiconductor layer, the body contact region containing second electrically conductive type impurity, and (a3) a carrier path region formed in the semiconductor layer such that the carrier path region does not make contact with the source and drain regions, but makes contact with the body contact region, the carrier path region containing second electrically conductive type impurity.Type: ApplicationFiled: June 6, 2002Publication date: December 12, 2002Applicant: NEC CorporationInventors: Risho Koh, Yukishige Saito, Jong-Wook Lee, Hisashi Takemura
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Publication number: 20020179975Abstract: One object of the present invention is to suppress a threshold voltage of at least an n-channel MISFET using a nitride of a high melting point metal at it's gate electrode. In order to achieve the object, a gate electrode 109 of a p-channel MISFET is constituted of a titanium nitride film 106 and a tungsten film 107 formed on the film 106 and a gate electrode 110a of an n-channel MISFET is constituted of a titanium nitride film 106a and a tungsten film 107 formed on the film 106a. The titanium nitride film 106a is formed by nitrogen ion implantation in the titanium nitride film 106 to decrease the work function.Type: ApplicationFiled: July 3, 2002Publication date: December 5, 2002Inventors: Hitoshi Wakabayashi, Yukishige Saito
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Patent number: 6483151Abstract: One object of the present invention is to suppress a threshold voltage of at least an n-channel MISFET using a nitride of a high melting point metal at it's gate electrode. In order to achieve the object, a gate electrode 109 of a p-channel MISFET is constituted of a titanium nitride film 106 and a tungsten film 107 formed on the film 106 and a gate electrode 110a of an n-channel MISFET is constituted of a titanium nitride film 106a and a tungsten film 107 formed on the film 106a. The titanium nitride film 106a is formed by nitrogen ion implantation in the titanium nitride film 106 to decrease the work function.Type: GrantFiled: January 4, 2001Date of Patent: November 19, 2002Assignee: NEC CorporationInventors: Hitoshi Wakabayashi, Yukishige Saito