Patents by Inventor Toshiaki Iwamatsu

Toshiaki Iwamatsu 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: 6958266
    Abstract: A partial oxide film (31) with well regions formed therebeneath isolates transistor formation regions in an SOI layer (3) from each other. A p-type well region (11) is formed beneath part of the partial oxide film (31) which isolates NMOS transistors from each other, and an n-type well region (12) is formed beneath part of the partial oxide film (31) which isolates PMOS transistors from each other. The p-type well region (11) and the n-type well region (12) are formed in side-by-side relation beneath part of the partial oxide film (31) which provides isolation between the NMOS and PMOS transistors. A body region is in contact with the well region (11) adjacent thereto. An interconnect layer formed on an interlayer insulation film (4) is electrically connected to the body region through a body contact provided in the interlayer insulation film (4). A semiconductor device having an SOI structure reduces a floating-substrate effect.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: October 25, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuo Yamaguchi, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Takuji Matsumoto, Shoichi Miyamoto
  • Patent number: 6953979
    Abstract: A partial oxide film (31) with well regions formed therebeneath isolates transistor formation regions in an SOI layer (3) from each other. A p-type well region (11) is formed beneath part of the partial oxide film (31) which isolates NMOS transistors from each other, and an n-type well region (12) is formed beneath part of the partial oxide film (31) which isolates PMOS transistors from each other. The p-type well region (11) and the n-type well region (12) are formed in side-by-side relation beneath part of the partial oxide film (31) which provides isolation between the NMOS and PMOS transistors. A body region is in contact with the well region (11) adjacent thereto. An interconnect layer formed on an interlayer insulation film (4) is electrically connected to the body region through a body contact provided in the interlayer insulation film (4). A semiconductor device having an SOI structure reduces a floating-substrate effect.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: October 11, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuo Yamaguchi, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Takuji Matsumoto, Shoichi Miyamoto
  • Publication number: 20050212056
    Abstract: To provide a semiconductor device capable of preventing drawbacks from being caused by metal pollution and a method of manufacturing the semiconductor device. A region (NR) and a region (PR) are defined by a trench isolation oxide film (ST21), a polysilicon film (PS21) is selectively provided on the trench isolation oxide film (ST21), a silicon layer (S22) is provided on the polysilicon film (PS21), and a side wall spacer (SW2) is provided on a side surface of the polysilicon film (PS21). The polysilicon film (PS21) is provided in a position corresponding to a top of a PN junction portion JP of a P-type well region (WR11) and an N-type well region (WR12) in an SOI layer 3 across the two well regions.
    Type: Application
    Filed: May 24, 2005
    Publication date: September 29, 2005
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Hideki Naruoka, Nobuyoshi Hattori, Shigeto Maegawa, Yasuo Yamaguchi, Takuji Matsumoto
  • Publication number: 20050208322
    Abstract: An embodiment of a multilayer wafer according to the invention includes a base substrate, a first layer associated with the base substrate, and a second layer on the first layer on side opposite from the base substrate in an axial direction and having a lateral edge. The first layer includes a ridge that protrudes axially and is disposed laterally adjacent the second layer measured in a direction normal to the axial direction for protecting the lateral edge. This ridge can surround portion the lateral edge in an axial cross-section for preventing edge falls. Also, the ridge can have an axial height greater than the axial thickness of the second layer. In one embodiment, the second layer includes an oxydizable semiconductor and the first layer includes an oxidized insulator.
    Type: Application
    Filed: February 24, 2005
    Publication date: September 22, 2005
    Applicant: S.O.I.TEC SILICON ON INSULATOR TECHNOLOGIES S.A.
    Inventors: Thierry Barge, Bruno Ghyselen, Toshiaki Iwamatsu, Hideki Naruoka, Junichiro Furihata, Kiyoshi Mitani
  • Publication number: 20050184342
    Abstract: An isolation insulating film (5) of partial-trench type is selectively formed in an upper surface of a silicon layer (4). A power supply line (21) is formed above the isolation insulating film (5). Below the power supply line (21), a complete isolation portion (23) reaching an upper surface of an insulating film (3) is formed in the isolation insulating film (5). In other words, a semiconductor device comprises a complete-isolation insulating film which is so formed as to extend from the upper surface of the silicon layer (4) and reach the upper surface of insulating film (3) below the power supply line (21). With this structure, it is possible to obtain the semiconductor device capable of suppressing variation in potential of a body region caused by variation in potential of the power supply line.
    Type: Application
    Filed: April 19, 2005
    Publication date: August 25, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Yuuichi Hirano, Shigeto Maegawa, Toshiaki Iwamatsu, Takuji Matsumoto, Shigenobu Maeda, Yasuo Yamaguchi
  • Patent number: 6933565
    Abstract: A silicon nitride film is formed between interlayer insulating films covering an upper surface of an element formed on a surface of a semiconductor layer. With this structure, a semiconductor device comprising an isolation insulating film of PTI structure, which suppresses a floating-body effect and improves isolation performance and breakdown voltage, and a method of manufacturing the semiconductor device can be obtained.
    Type: Grant
    Filed: December 6, 2000
    Date of Patent: August 23, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Toshiaki Iwamatsu, Yuuichi Hirano
  • Publication number: 20050167673
    Abstract: Provided are a thin-film transistor formed by connecting polysilicon layers having different conductivity types with each other which prevents occurrence of inconvenience resulting from diffusion of impurities and a method of fabricating the same. A drain (6), a channel (7) and a source (8) are integrally formed on a surface of a second oxide film (4) by polysilicon. The drain (6) is formed to be connected with a pad layer (3) (second polycrystalline semiconductor layer) through a contact hole (5) which is formed to reach an upper surface of the pad layer (3). The pad layer (3) positioned on a bottom portion of the contact hole (5) (opening) is provided with a boron implantation region BR.
    Type: Application
    Filed: March 14, 2005
    Publication date: August 4, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu, Shigenobu Maeda, Il-Jung Kim, Kazuhito Tsutsumi, Hirotada Kuriyama, Yoshiyuki Ishigaki, Motomu Ukita, Toshiaki Tsutsumi
  • Publication number: 20050156242
    Abstract: A partial oxide film (31) with well regions formed therebeneath isolates transistor formation regions in an SOI layer (3) from each other. A p-type well region (11) is formed beneath part of the partial oxide film (31) which isolates NMOS transistors from each other, and an n-type well region (12) is formed beneath part of the partial oxide film (31) which isolates PMOS transistors from each other. The p-type well region (11) and the n-type well region (12) are formed in side-by-side relation beneath part of the partial oxide film (31) which provides isolation between the NMOS and PMOS transistors. A body region is in contact with the well region (11) adjacent thereto. An interconnect layer formed on an interlayer insulation film (4) is electrically connected to the body region through a body contact provided in the interlayer insulation film (4). A semiconductor device having an SOI structure reduces a floating-substrate effect.
    Type: Application
    Filed: January 14, 2005
    Publication date: July 21, 2005
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yasuo Yamaguchi, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Takuji Matsumoto, Shoichi Miyamoto
  • Patent number: 6914307
    Abstract: A semiconductor device includes a semiconductor layer, a plurality of semiconductor elements formed on the semiconductor layer, and an isolation film provided in a surface of the semiconductor layer, semiconductor elements being electrically isolated from each other by the isolation film. The semiconductor device also includes a PN junction portion provided under the isolation film and formed by two semiconductor regions of different conductivity types in the semiconductor layer. The isolation film includes a nitride film provided in a position corresponding to a top of the PN junction portion and has a substantially uniform thickness across the two semiconductor regions and an upper oxide film and a lower oxide film which are provided in upper and lower portions of the nitride film. The surface of the semiconductor layer is silicidized in such a state that a surface of the isolation film is exposed.
    Type: Grant
    Filed: September 9, 2003
    Date of Patent: July 5, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Hideki Naruoka, Nobuyoshi Hattori, Shigeto Maegawa, Yasuo Yamaguchi, Takuji Matsumoto
  • Publication number: 20050133864
    Abstract: Plural trench isolation films (4) are provided with portions of an SOI layer (3) interposed therebetween in a surface of the SOI layer (3) in a resistor region (RR) where a spiral inductor (SI) is to be provided. Resistive element (30) are formed on the trench isolation films (4), respectively. Each of the trench isolation films (4) includes a central portion which passes through the SOI layer (3) and reaches a buried oxide film (2) to include a full-trench isolation structure, and opposite side portions each of which passes through only a portion of the SOI layer (3) and is located on the SOI layer 3 to include a partial-trench isolation structure. Thus, each of the trench isolation films (4) includes a hybrid-trench isolation structure.
    Type: Application
    Filed: December 3, 2004
    Publication date: June 23, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6902988
    Abstract: The invention relates to a process for the treatment of substrates (1) for microelectronics or optoelectronics comprising a working layer (6) at least partially composed of an oxidizable material on at least one of their faces, this process comprising: a first sacrificial oxidation stage for removing material constituting the working layer (6) over a certain surface thickness of each substrate (1), a stage of polishing (200) the face which has been subjected to the first sacrificial oxidation stage (100), and a second sacrificial oxidation stage for again removing material constituting the working layer (6) on the polished face (17).
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: June 7, 2005
    Assignee: S.O.I.Tec Silicon on Insulator Technologies S.A.
    Inventors: Thierry Barge, Bruno Ghyselen, Toshiaki Iwamatsu, Hideki Naruoka, Junichiro Furihata, Kiyoshi Mitani
  • Publication number: 20050101091
    Abstract: The present invention provides a method of fabricating a semiconductor device in which deterioration in a transistor characteristic is prevented by preventing a channel stop implantation layer from being formed in an active region. A resist mask is formed so as to have an opening over a region in which a PMOS transistor is formed. Channel stop implantation is performed with energy by which ions pass through a partial isolation oxide film and a peak of an impurity profile is generated in an SOI layer, thereby forming a channel stop layer in the SOI layer under the partial isolation oxide film, that is, an isolation region. An impurity to be implanted here is an N-type impurity. In the case of using phosphorus, its implantation energy is set to, for example, 60 to 120 keV, and the density of the channel stop layer is set to 1×1017 to 1×1019/cm3. At this time, the impurity of channel stop implantation is not stopped in the SOI layer corresponding to the active region.
    Type: Application
    Filed: December 15, 2004
    Publication date: May 12, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Takuji Matsumoto, Shigenobu Maeda
  • Publication number: 20050101070
    Abstract: An SOI substrate is formed of a silicon oxide substrate and a silicon film. A surface of the silicon film is oxidized and a silicon oxide film is thereby formed. A polycrystalline silicon and a silicon nitride film are formed on the silicon oxide film in this order. Then, a trench is formed in a region. The trench is filled with an insulating material, e.g., a silicon oxide film.
    Type: Application
    Filed: November 2, 2004
    Publication date: May 12, 2005
    Inventors: Mikio Tsujiuchi, Toshiaki Iwamatsu
  • Patent number: 6879002
    Abstract: A semiconductor device comprising an SOI substrate fabricated by forming a silicon layer 3 on an insulating layer 2, a plurality of active regions 3 horizontally arranged in the silicon layer 3, and element isolating parts 5 having a trench-like shape which is made of an insulator 5 embedded between the active regions 3 in the silicon layer 3, wherein the insulating layer 2 has spaces 6 positioned in the vicinity of interfaces between the active regions and the element isolating parts 5, whereby it becomes possible to reduce fixed charges or holes existing on a side of the insulating layer in interfaces between the silicon layer and the insulating layer, which fixed charges or holes are generated in a process of oxidation for forming the insulating layer on a bottom surface of the silicon layer.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: April 12, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Shoichi Miyamoto, Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6875663
    Abstract: The present invention provides a method of fabricating a semiconductor device in which deterioration in a transistor characteristic is prevented by preventing a channel stop implantation layer from being formed in an active region. A resist mask is formed so as to have an opening over a region in which a PMOS transistor is formed. Channel stop implantation is performed with energy by which ions pass through a partial isolation oxide film and a peak of an impurity profile is generated in an SOI layer, thereby forming a channel stop layer in the SOI layer under the partial isolation oxide film, that is, an isolation region. An impurity to be implanted here is an N-type impurity. In the case of using phosphorus, its implantation energy is set to, for example, 60 to 120 keV, and the density of the channel stop layer is set to 1×1017 to 1×1019/cm3. At this time, the impurity of channel stop implantation is not stopped in the SOI layer corresponding to the active region.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: April 5, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Takuji Matsumoto, Shigenobu Maeda
  • Patent number: 6872979
    Abstract: A semiconductor substrate that prevents formation of particles from an edge part of the substrate. The substrate contains an on-substrate oxide film and an SOI layer stacked on the oxide film. A molten layer is formed on the edge part of the on-substrate oxide film and the SOI layer by mixing the SOI layer and the on-substrate oxide film to cover the edge part. An epitaxial layer may also be formed on the edge part of the on-substrate oxide film and the SOI layer to cover the edge part.
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: March 29, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Yoshiko Yoshida, Hideki Naruoka, Yasuhiro Kimura, Yasuo Yamaguchi, Toshiaki Iwamatsu, Yuuichi Hirano
  • Publication number: 20050037524
    Abstract: The invention relates to improvements in a method of manufacturing a semiconductor device in which deterioration in a transistor characteristic is avoided by preventing a channel stop implantation layer from being formed in an active region. After patterning a nitride film (22), the thickness of an SOI layer 3 is measured (S2) and, by using the result of measurement, etching conditions (etching time and the like) for SOI layer 3 are determined (S3). To measure the thickness of SOI layer 3, it is sufficient to use spectroscopic ellipsometry which irradiates the surface of a substance with linearly polarized light and observes elliptically polarized light reflected by the surface of a substance. The etching condition determined is used and a trench TR2 is formed by using patterned nitride film 22 as an etching mask (S4).
    Type: Application
    Filed: September 27, 2004
    Publication date: February 17, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Mikio Tsujiuchi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Shigeto Maegawa
  • Patent number: 6841400
    Abstract: The invention relates to improvements in a method of manufacturing a semiconductor device in which deterioration in a transistor characteristic is avoided by preventing a channel stop implantation layer from being formed in an active region. After patterning a nitride film (22), the thickness of an SOI layer 3 is measured (S2) and, by using the result of measurement, etching conditions (etching time and the like) for SOI layer 3 are determined (S3). To measure the thickness of SOI layer 3, it is sufficient to use spectroscopic ellipsometry which irradiates the surface of a substance with linearly polarized light and observes elliptically polarized light reflected by the surface of a substance. The etching condition determined is used and a trench TR2 is formed by using patterned nitride film 22 as an etching mask (S4).
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: January 11, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Mikio Tsujiuchi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Shigeto Maegawa
  • Publication number: 20040253458
    Abstract: A semiconductor wafer includes an oxide film above a silicon layer, and a porous silicon layer which is located above the oxide film and serves as a gettering layer. Gettering of impurities from a silicon layer is not interrupted by the oxide film since the porous silicon layer is placed above the oxide film. The semiconductor wafer having the structure above can be produced by a bonding method. Bonding strength relative to the oxide film is ensured by placing a growth silicon layer between the oxide film and the porous silicon layer, compared with the case in which the oxide film and the porous silicon layer are directly bonded.
    Type: Application
    Filed: July 14, 2004
    Publication date: December 16, 2004
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Takuji Matsumoto, Toshiaki Iwamatsu
  • Publication number: 20040227185
    Abstract: A semiconductor device and its manufacturing method are provided which can properly avoid reduction of isolation breakdown voltage without involving adverse effects like an increase in junction capacitance. Impurity-introduced regions (11) are formed after a silicon layer (3) has been thinned through formation of recesses (14). Therefore n-type impurities are not implanted into the portions of the p-type silicon layer (3) that are located between the bottoms of element isolation insulating films (5) and the top surface of a BOX layer (2), which avoids reduction of isolation breakdown voltage. Furthermore, since the impurity-introduced regions (11) are formed to reach the upper surface of the BOX layer (2), the junction capacitance of source/drain regions (12) is not increased.
    Type: Application
    Filed: January 12, 2004
    Publication date: November 18, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Takashi Ipposhi, Toshiaki Iwamatsu, Yuuichi Hirano