Patents by Inventor Ryohei Kitao

Ryohei Kitao 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: 7229916
    Abstract: A method of manufacturing a semiconductor device is to be provided, which improves filling performance of a conductive layer to be formed by an electrolytic plating process in an interconnect trench or a via hole, and achieves a higher in-plane uniformity in bottom-up performance. An electrolytic plating process to fill with a conductive layer at least one of an interconnect trench and a via hole formed in a dielectric layer on a semiconductor substrate includes a first step of executing a plating operation under a predetermined integrated current density, which is a product of a current density representing a current value supplied per unit area of a plating solution containing a material which constitutes the conductive layer and a plating time, and a second step of executing a plating operation under a lower current density than that of the first step.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: June 12, 2007
    Assignee: NEC Electronics Corporation
    Inventors: Ryohei Kitao, Koji Arita
  • Publication number: 20070045861
    Abstract: A semiconductor device has a semiconductor substrate, and a multi-layered wiring arrangement provided thereon. The multi-layered wring arrangement includes at least one insulating layer structure having a metal wiring pattern formed therein. The insulating layer structure includes a first SiOCH layer, a second SiOCH layer formed on the first SiOCH layer, and a silicon dioxide (SiO2) layer formed on the second SiOCH layer. The second SiOCH layer features a carbon (C) density lower than that of the first SiOCH layer, a hydrogen (H) density lower than that of the first SiOCH layer, and an oxygen (O) density higher than that of the first SiOCH layer.
    Type: Application
    Filed: November 2, 2006
    Publication date: March 1, 2007
    Applicant: NEC Electronics Corporation
    Inventors: Koichi Ohto, Tatsuya Usami, Noboru Morita, Sadayuki Ohnishi, Koji Arita, Ryohei Kitao, Yoichi Sasaki
  • Patent number: 7132732
    Abstract: A semiconductor device has a semiconductor substrate, and a multi-layered wiring arrangement provided thereon. The multi-layered wring arrangement includes at least one insulating layer structure having a metal wiring pattern formed therein. The insulating layer structure includes a first SiOCH layer, a second SiOCH layer formed on the first SiOCH layer, and a silicon dioxide (SiO2) layer formed on the second SiOCH layer. The second SiOCH layer features a carbon (C) density lower than that of the first SiOCH layer, a hydrogen (H) density lower than that of the first SiOCH layer, and an oxygen (O) density higher than that of the first SiOCH layer.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: November 7, 2006
    Assignee: NEC Electronics Corporation
    Inventors: Koichi Ohto, Tatsuya Usami, Noboru Morita, Sadayuki Ohnishi, Koji Arita, Ryohei Kitao, Yoichi Sasaki
  • Patent number: 7074698
    Abstract: A method of fabricating a semiconductor device using a PECVD method is provided, which improves the adhesion strength of a deposited dielectric layer to an underlying layer and the reliability of the deposited dielectric layer. After placing a substrate in a chamber, a gas having a thermal conductivity of 0.1 W/mK or greater (e.g., H2 or He) is introduced into the chamber, thereby contacting the gas with the substrate for stabilization of a temperature of the substrate. A desired dielectric layer is deposited on or over the substrate in the chamber using a PECVD method after the step of introducing the gas. As the desired dielectric layer, a dielectric layer having a low dielectric constant, such as a SiCH, SiCHN, or SiOCH layer, is preferably used.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: July 11, 2006
    Assignee: NEC Electronics Corporation
    Inventors: Noboru Morita, Tatsuya Usami, Koichi Ohto, Sadayuki Ohnishi, Koji Arita, Ryohei Kitao, Yoichi Sasaki
  • Publication number: 20060141778
    Abstract: A manufacturing method of a semiconductor device including a step of forming a via hole in an insulation layer including an organic low dielectric film, such as MSQ, SiC, and SiCN, and then embedding a wiring material in the via hole through a barrier metal. According to this method, a plasma treatment is performed after the via hole is formed and before the barrier metal is deposited, using a He/H2 gas capable of replacing groups (methyl groups) made of organic constituents and covering the surface of the exposed organic low dielectric film (MSQ) with hydrogen, or a He gas capable decomposing the groups (methyl groups) without removing organic low dielectric molecules. As a result, the surface of the low dielectric film (MSQ) is reformed to be hydrophilic and adhesion to the barrier metal is hence improved, thereby making it possible to prevent the occurrence of separation of the barrier metal and scratches.
    Type: Application
    Filed: February 23, 2006
    Publication date: June 29, 2006
    Inventors: Takashi Tonegawa, Koji Arita, Tatsuya Usami, Noboru Morita, Koichi Ohto, Yoichi Sasaki, Sadayuki Ohnishi, Ryohei Kitao
  • Patent number: 6989328
    Abstract: In copper plating using a damascene method, in order to prevent cost rise, dishing, erosion and the like due to the protrusion of plating on the dense wiring area to increase the time for CMP polishing, the copper plating is performed so that the current step of the copper plating has only one step for flowing current in the direction opposite to the direction of growing the plating as shown in FIG. 1. In this time, this opposite direction current step is performed under the condition of a current-time product within a range between 1.0 and 120 mAƗsec/cm2.
    Type: Grant
    Filed: February 13, 2004
    Date of Patent: January 24, 2006
    Assignee: NEC Electronics Corporation
    Inventors: Koji Arita, Kaoru Mikagi, Ryohei Kitao
  • Publication number: 20050048769
    Abstract: A method of manufacturing a semiconductor device is to be provided, which improves filling performance of a conductive layer to be formed by an electrolytic plating process in an interconnect trench or a via hole, and achieves a higher in-plane uniformity in bottom-up performance. An electrolytic plating process to fill with a conductive layer at least one of an interconnect trench and a via hole formed in a dielectric layer on a semiconductor substrate includes a first step of executing a plating operation under a predetermined integrated current density, which is a product of a current density representing a current value supplied per unit area of a plating solution containing a material which constitutes the conductive layer and a plating time, and a second step of executing a plating operation under a lower current density than that of the first step.
    Type: Application
    Filed: July 16, 2004
    Publication date: March 3, 2005
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Ryohei Kitao, Koji Arita
  • Publication number: 20040185668
    Abstract: A method of fabricating a semiconductor device using a PECVD method is provided, which improves the adhesion strength of a deposited dielectric layer to an underlying layer and the reliability of the deposited dielectric layer. After placing a substrate in a chamber, a gas having a thermal conductivity of 0.1 W/mK or greater (e.g.. H2 or He) is introduced into the chamber, thereby contacting the gas with the substrate for stabilization of a temperature of the substrate. A desired dielectric layer is deposited on or over the substrate in the chamber using a PECVD method after the step of introducing the gas. As the desired dielectric layer, a dielectric layer having a low dielectric constant, such as a SiCH, SiCHN, or SiOCH layer, is preferably used.
    Type: Application
    Filed: January 30, 2004
    Publication date: September 23, 2004
    Applicant: NEC Electronics Corporation
    Inventors: Noboru Morita, Tatsuya Usami, Koichi Ohto, Sadayuki Ohnishi, Koji Arita, Ryohei Kitao, Yoichi Sasaki
  • Publication number: 20040183162
    Abstract: A semiconductor device has a semiconductor substrate, and a multi-layered wiring arrangement provided thereon. The multi-layered wring arrangement includes at least one insulating layer structure having a metal wiring pattern formed therein. The insulating layer structure includes a first SiOCH layer, a second SiOCH layer formed on the first SiOCH layer, and a silicon dioxide (SiO2) layer formed on the second SiOCH layer. The second SiOCH layer features a carbon (C) density lower than that of the first SiOCH layer, a hydrogen (H) density lower than that of the first SiOCH layer, and an oxygen (O) density higher than that of the first SiOCH layer.
    Type: Application
    Filed: January 29, 2004
    Publication date: September 23, 2004
    Applicant: NEC Electronics Corporation
    Inventors: Koichi Ohto, Tatsuya Usami, Noboru Morita, Sadayuki Ohnishi, Koji Arita, Ryohei Kitao, Yoichi Sasaki
  • Publication number: 20040161928
    Abstract: In copper plating using a damascene method, in order to prevent cost rise, dishing, erosion and the like due to the protrusion of plating on the dense wiring area to increase the time for CMP polishing, the copper plating is performed so that the current step of the copper plating has only one step for flowing current in the direction opposite to the direction of growing the plating as shown in FIG. 1. In this time, this opposite direction current step is performed under the condition of a current-time product within a range between 1.0 and 120 mA×sec/cm2.
    Type: Application
    Filed: February 13, 2004
    Publication date: August 19, 2004
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Koji Arita, Kaoru Mikagi, Ryohei Kitao
  • Publication number: 20030155657
    Abstract: A manufacturing method of a semiconductor device including a step of forming a via hole in an insulation layer including an organic low dielectric film, such as MSQ, SiC, and SiCN, and then embedding a wiring material in the via hole through a barrier metal. According to this method, a plasma treatment is performed after the via hole is formed and before the barrier metal is deposited, using a He/H2 gas capable of replacing groups (methyl groups) made of organic constituents and covering the surface of the exposed organic low dielectric film (MSQ) with hydrogen, or a He gas capable decomposing the groups (methyl groups) without removing organic low dielectric molecules. As a result, the surface of the low dielectric film (MSQ) is reformed to be hydrophilic and adhesion to the barrier metal is hence improved, thereby making it possible to prevent the occurrence of separation of the barrier metal and scratches.
    Type: Application
    Filed: February 13, 2003
    Publication date: August 21, 2003
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Takashi Tonegawa, Koji Arita, Tatsuya Usami, Noboru Morita, Koichi Ohto, Yoichi Sasaki, Sadayuki Ohnishi, Ryohei Kitao