Patents by Inventor Takahisa Yamaha

Takahisa Yamaha 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: 8237221
    Abstract: The semiconductor device according to the present invention includes a semiconductor layer, a trench formed by digging the semiconductor layer from the surface thereof, a gate insulating film formed on the inner surface of the trench, and a gate electrode made of silicon embedded in the trench through the gate insulating film. The gate electrode has a high-conductivity portion formed to cover the gate insulating film with a relatively high conductivity and a low-conductivity portion formed on a region inside the high-conductivity portion with a relatively low conductivity.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: August 7, 2012
    Assignee: Rohm Co., Ltd.
    Inventors: Ryotaro Yagi, Isamu Nishimura, Takahisa Yamaha
  • Patent number: 8164160
    Abstract: A semiconductor device according to the present invention has a multilayer wiring structure laminating and disposing a plurality of with sandwiching an insulating film and includes: a copper wire having copper as a main component; an insulating film formed on the copper wire; an aluminum wire having aluminum as a main component and formed on the insulating film to be electrically connected to the copper wire via a via hole formed to penetrate through the insulating film; and a surface protective film formed on the aluminum wire; and the surface protective film formed with a pad opening exposing a portion of the aluminum wire as an electrode pad for electrical connection with an external portion.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: April 24, 2012
    Assignee: Rohm Co., Ltd.
    Inventors: Yuichi Nakao, Takahisa Yamaha
  • Patent number: 8125084
    Abstract: A semiconductor device according to the present invention includes: a semiconductor substrate; a first copper interconnection provided on the semiconductor substrate; an insulating layer provided over the first copper interconnection and having a hole extending therethrough to the first copper interconnection; a barrier layer composed of a tantalum-containing material and covering at least a sidewall of the hole and a part of the first copper interconnection exposed in the hole; and a second copper interconnection provided in intimate contact with the barrier layer and electrically connected to the first copper interconnection via the barrier layer; wherein the barrier layer has a nitrogen concentration profile such that the concentration of nitrogen contained in the material varies to be lower in a boundary portion of the barrier layer adjacent to the first copper interconnection and in a boundary portion of the barrier layer adjacent to the second copper interconnection and higher in an intermediate portion
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: February 28, 2012
    Assignee: ROHM Co., Ltd.
    Inventors: Ryosuke Nakagawa, Takahisa Yamaha, Yuichi Nakao, Katsumi Sameshima, Satoshi Kageyama
  • Publication number: 20110298044
    Abstract: The semiconductor device according to the present invention includes a semiconductor layer, a trench formed by digging the semiconductor layer from the surface thereof, a gate insulating film formed on the inner surface of the trench, and a gate electrode made of silicon embedded in the trench through the gate insulating film. The gate electrode has a high-conductivity portion formed to cover the gate insulating film with a relatively high conductivity and a low-conductivity portion formed on a region inside the high-conductivity portion with a relatively low conductivity.
    Type: Application
    Filed: August 22, 2011
    Publication date: December 8, 2011
    Inventors: Ryotaro YAGI, Isamu Nishimura, Takahisa Yamaha
  • Patent number: 8022472
    Abstract: The semiconductor device according to the present invention includes a semiconductor layer, a trench formed by digging the semiconductor layer from the surface thereof, a gate insulating film formed on the inner surface of the trench, and a gate electrode made of silicon embedded in the trench through the gate insulating film. The gate electrode has a high-conductivity portion formed to cover the gate insulating film with a relatively high conductivity and a low-conductivity portion formed on a region inside the high-conductivity portion with a relatively low conductivity.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: September 20, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Ryotaro Yagi, Isamu Nishimura, Takahisa Yamaha
  • Publication number: 20100190335
    Abstract: In a method of manufacturing a semiconductor device according to the present invention, a wiring trench is formed on the surface of an insulating film, and the inner surface of this wiring trench is thereafter coated with an alloy film made of an alloy material containing copper and a prescribed metallic element. After this coating with the alloy film, a copper film is laminated on the insulating film to fill up the wiring trench. Then, unnecessary portions of the copper film outside the wiring trench are removed, so that the surface of the copper film remaining in the wiring trench is generally flush with the surface of the insulating film. Thereafter heat treatment is performed. The prescribed metallic element is deposited on the wiring trench due to this heat treatment. Then, the prescribed metallic element deposited on the wiring trench is removed.
    Type: Application
    Filed: March 15, 2010
    Publication date: July 29, 2010
    Applicant: ROHM CO., LTD.
    Inventors: Yuichi Nakao, Takahisa Yamaha
  • Publication number: 20100032837
    Abstract: A semiconductor device according to the present invention includes: a semiconductor substrate; a first copper interconnection provided on the semiconductor substrate; an insulating layer provided over the first copper interconnection and having a hole extending therethrough to the first copper interconnection; a barrier layer composed of a tantalum-containing material and covering at least a sidewall of the hole and a part of the first copper interconnection exposed in the hole; and a second copper interconnection provided in intimate contact with the barrier layer and electrically connected to the first copper interconnection via the barrier layer; wherein the barrier layer has a nitrogen concentration profile such that the concentration of nitrogen contained in the material varies to be lower in a boundary portion of the barrier layer adjacent to the first copper interconnection and in a boundary portion of the barrier layer adjacent to the second copper interconnection and higher in an intermediate portion
    Type: Application
    Filed: October 11, 2007
    Publication date: February 11, 2010
    Applicant: ROHM CO., LTD
    Inventors: Ryosuke Nakagawa, Takahisa Yamaha, Yuichi Nakao, Katsumi Sameshima, Satoshi Kageyama
  • Publication number: 20090140330
    Abstract: The semiconductor device according to the present invention includes a semiconductor layer, a trench formed by digging the semiconductor layer from the surface thereof, a gate insulating film formed on the inner surface of the trench, and a gate electrode made of silicon embedded in the trench through the gate insulating film. The gate electrode has a high-conductivity portion formed to cover the gate insulating film with a relatively high conductivity and a low-conductivity portion formed on a region inside the high-conductivity portion with a relatively low conductivity.
    Type: Application
    Filed: December 3, 2008
    Publication date: June 4, 2009
    Applicant: ROHM CO., LTD.
    Inventors: Ryotaro Yagi, Isamu Nishimura, Takahisa Yamaha
  • Publication number: 20080296730
    Abstract: A semiconductor device according to the present invention has a multilayer wiring structure laminating and disposing a plurality of with sandwiching an insulating film and includes: a copper wire having copper as a main component; an insulating film formed on the copper wire; an aluminum wire having aluminum as a main component and formed on the insulating film to be electrically connected to the copper wire via a via hole formed to penetrate through the insulating film; and a surface protective film formed on the aluminum wire; and the surface protective film formed with a pad opening exposing a portion of the aluminum wire as an electrode pad for electrical connection with an external portion.
    Type: Application
    Filed: May 30, 2008
    Publication date: December 4, 2008
    Applicant: ROHM CO., LTD.
    Inventors: Yuichi Nakao, Takahisa Yamaha
  • Publication number: 20080296772
    Abstract: A semiconductor device according to the present invention includes: a lower wire having copper as a main component; an insulating film formed on the lower wire; an upper wire formed on the insulating film; a tungsten plug penetrating through the insulating film and formed of tungsten for electrically connecting the lower wire and the upper wire; and a barrier layer interposed between the lower wire and the tungsten plug; and the barrier layer including a tantalum film contacting the lower wire and a titanium nitride film contacting the tungsten plug.
    Type: Application
    Filed: May 30, 2008
    Publication date: December 4, 2008
    Applicant: ROHM CO., LTD.
    Inventors: Yuichi Nakao, Takahisa Yamaha
  • Publication number: 20080122094
    Abstract: In a method of manufacturing a semiconductor device according to the present invention, a wiring trench is formed on the surface of an insulating film, and the inner surface of this wiring trench is thereafter coated with an alloy film made of an alloy material containing copper and a prescribed metallic element. After this coating with the alloy film, a copper film is laminated on the insulating film to fill up the wiring trench. Then, unnecessary portions of the copper film outside the wiring trench are removed, so that the surface of the copper film remaining in the wiring trench is generally flush with the surface of the insulating film. Thereafter heat treatment is performed. The prescribed metallic element is deposited on the wiring trench due to this heat treatment. Then, the prescribed metallic element deposited on the wiring trench is removed.
    Type: Application
    Filed: November 27, 2007
    Publication date: May 29, 2008
    Applicant: ROHM CO., LTD.
    Inventors: Yuichi Nakao, Takahisa Yamaha
  • Patent number: 7211902
    Abstract: A semiconductor device having a semiconductor substrate and a bonding pad portion formed on the semiconductor substrate, the bonding pad portion having: an insulating film formed on the semiconductor substrate and a first-level conductive pad layer of a large island shape formed on the insulating film; first-level to (n?1)-level (n is an integer of 3 or larger) interlayer insulating films formed on and over the insulating film; second-level to n-level conductive pad layers formed on the interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer was formed; a plurality of small diameter first through holes from the first-level to (n?1) level formed through the first-level to (n?1) level interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer; a plurality of first contact plugs filled in the small diameter first through holes from the first-level to (n?1)-level, the first contact plugs at each level being cond
    Type: Grant
    Filed: February 15, 2006
    Date of Patent: May 1, 2007
    Assignee: Yamaha Corporation
    Inventor: Takahisa Yamaha
  • Publication number: 20060138662
    Abstract: A semiconductor device having a semiconductor substrate and a bonding pad portion formed on the semiconductor substrate, the bonding pad portion having: an insulating film formed on the semiconductor substrate and a first-level conductive pad layer of a large island shape formed on the insulating film; first-level to (n?1)-level (n is an integer of 3 or larger) interlayer insulating films formed on and over the insulating film; second-level to n-level conductive pad layers formed on the interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer was formed; a plurality of small diameter first through holes from the first-level to (n?1) level formed through the first-level to (n?1) level interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer; a plurality of first contact plugs filled in the small diameter first through holes from the first-level to (n?1)-level, the first contact plugs at each level being cond
    Type: Application
    Filed: February 15, 2006
    Publication date: June 29, 2006
    Inventor: Takahisa Yamaha
  • Patent number: 7067928
    Abstract: A semiconductor device having a semiconductor substrate and a bonding pad portion formed on the semiconductor substrate, the bonding pad portion having: an insulating film formed on the semiconductor substrate and a first-level conductive pad layer of a large island shape formed on the insulating film; first-level to (n?1)-level (n is an integer of 3 or larger) interlayer insulating films formed on and over the insulating film; second-level to n-level conductive pad layers formed on the interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer was formed; a plurality of small diameter first through holes from the first-level to (n?1) level formed through the first-level to (n?1) level interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer; a plurality of first contact plugs filled in the small diameter first through holes from the first-level to (n?1)-level, the first contact plugs at each level being cond
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: June 27, 2006
    Assignee: Yamaha Corpoation
    Inventor: Takahisa Yamaha
  • Patent number: 6921714
    Abstract: A plurality of intermediate layers are formed on a base layer. Each of the intermediate layers include a conductive pad which is formed on both the insulating film of the immediately preceding layer and an interlayer insulating film which is formed on both the conductive pad of the same intermediate layer and the insulating film of the preceding intermediate layer. A plurality of through holes are formed in each of the interlayer insulating films and are filled with conductive material. The conductive pad of each intermediate layer is in electrical contact with the conductive material in the through holes of the top most intermediate layer. An insulating film is formed on both this conductive pad and the insulating film of the top most intermediate layer. A hole is formed in this insulating film which hole is substantially the same size as the conductive pad. A bonding pad is formed on the conductive pad in the through hole.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: July 26, 2005
    Assignee: Yamaha Corporation
    Inventor: Takahisa Yamaha
  • Publication number: 20050146042
    Abstract: A semiconductor device having a semiconductor substrate and a bonding pad portion formed on the semiconductor substrate, the bonding pad portion having: an insulating film formed on the semiconductor substrate and a first-level conductive pad layer of a large island shape formed on the insulating film; first-level to (n?1)-level (n is an integer of 3 or larger) interlayer insulating films formed on and over the insulating film; second-level to n-level conductive pad layers formed on the interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer was formed; a plurality of small diameter first through holes from the first-level to (n?1) level formed through the first-level to (n?1) level interlayer insulating films in areas generally corresponding to an area where the first conductive pad layer; a plurality of first contact plugs filled in the small diameter first through holes from the first-level to (n?1)-level, the first contact plugs at each level being cond
    Type: Application
    Filed: March 8, 2005
    Publication date: July 7, 2005
    Inventor: Takahisa Yamaha
  • Patent number: 6888183
    Abstract: After a MOS type transistor is formed on the surface of a semiconductor substrate, an interlayer insulating film covering the transistor is formed. The insulating film includes a silicon oxide film made of hydrogen silsesquioxane resin in a ceramic state. After a wiring layer is formed on the insulating film, a silicon oxide film as a surface protection film is formed on the insulating film, covering the wiring layer. In order to reduce process damages, heat treatment is performed 30 minutes at 400° C. in a nitrogen gas atmosphere. With this heat treatment, hydrogen in the silicon oxide film is released and diffuses into the channel region of the transistor to lower interfacial energy levels. Since the silicon nitride film does not transmit hydrogen, it is not necessary for the heat treatment atmosphere to contain hydrogen. A variation in threshold voltages of MOS type transistors can be easily lowered.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: May 3, 2005
    Assignee: Yamaha Corporation
    Inventor: Takahisa Yamaha
  • Patent number: 6555465
    Abstract: A first wiring layer is formed on an insulating film. The first wiring layer is formed by sequentially laminating a barrier layer, an Al alloy layer, and an antireflection layer. The antireflection layer is formed by sequentially laminating a Ti layer, a TiN layer, and a TiON layer. After an interlayer insulating film is formed on the first wiring layer, a contact hole is formed through the interlayer insulating film and a tight adhesion layer is formed on an inner surface of the contact hole. The tight adhesion layer is formed by sequentially laminating a Ti layer, a TiN layer, a TiON layer, and a TiN layer. A W plug is embedded in the contact hole through CVD using WF6. Thereafter, an Al alloy layer and an antireflection layer are sequentially deposited and patterned to form a second wiring layer.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: April 29, 2003
    Assignee: Yamaha Corp.
    Inventor: Takahisa Yamaha
  • Patent number: 6541373
    Abstract: After a MOS type transistor is formed on the surface of a semiconductor substrate, an interlayer insulating film covering the transistor is formed. The insulating film includes a silicon oxide film made of hydrogen silsesquioxane resin in a ceramic state. After a wiring layer is formed on the insulating film, a silicon oxide film as a surface protection film is formed on the insulating film, covering the wiring layer. In order to reduce process damages, heat treatment is performed 30 minutes at 400° C. in a nitrogen gas atmosphere. With this heat treatment, hydrogen in the silicon oxide film is released and diffuses into the channel region of the transistor to lower interfacial energy levels. Since the silicon nitride film does not transmit hydrogen, it is not necessary for the heat treatment atmosphere to contain hydrogen. A variation in threshold voltages of MOS type transistors can be easily lowered.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: April 1, 2003
    Assignee: Yamaha Corporation
    Inventor: Takahisa Yamaha
  • Publication number: 20030003707
    Abstract: A first wiring layer is formed on an insulating film. The first wiring layer is formed by sequentially laminating a barrier layer, an Al alloy layer, and an antireflection layer. The antireflection layer is formed by sequentially laminating a Ti layer, a TiN layer, and a TiON layer. After an interlayer insulating film is formed on the first wiring layer, a contact hole is formed through the interlayer insulating film and a tight adhesion layer is formed on an inner surface of the contact hole. The tight adhesion layer is formed by sequentially laminating a Ti layer, a TiN layer, a TiON layer, and a TiN layer. A W plug is embedded in the contact hole through CVD using WF6. Thereafter, an Al alloy layer and an antireflection layer are sequentially deposited and patterned to form a second wiring layer.
    Type: Application
    Filed: June 19, 2002
    Publication date: January 2, 2003
    Applicant: Yamaha Corp.
    Inventor: Takahisa Yamaha