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: 6818536
    Abstract: A sidewall oxide layer and a sidewall insulation layer are formed to cover the edge portion of an SOI layer. A channel stopper region is formed in the vicinity of the edge portion of the SOI layer. A protruded insulation layer is formed on the channel stopper region. A gate electrode extends from a region over the SOI layer to the protruded insulation layer and the sidewall insulation layer. In this way, reduction in threshold voltage Vth of a parasitic MOS transistor at the edge portion of the SOI layer can be suppressed.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: November 16, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu, Yasuo Yamaguchi
  • Publication number: 20040222465
    Abstract: A semiconductor device which achieves reductions in malfunctions and operating characteristic variations by reducing the gain of a parasitic bipolar transistor, and a method of manufacturing the same are provided. A silicon oxide film (6) is formed partially on the upper surface of a silicon layer (3). A gate electrode (7) of polysilicon is formed partially on the silicon oxide film (6). A portion of the silicon oxide film (6) underlying the gate electrode (7) functions as a gate insulation film. A silicon nitride film (9) is formed on each side surface of the gate electrode (7), with a silicon oxide film (8) therebetween. The silicon oxide film (8) and the silicon nitride film (9) are formed on the silicon oxide film (6). The width (W1) of the silicon oxide film (8) in a direction of the gate length is greater than the thickness (T1) of the silicon oxide film (6).
    Type: Application
    Filed: June 15, 2004
    Publication date: November 11, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Hirokazu Sayama, Shigenobu Maeda, Toshiaki Iwamatsu, Kazunobu Ota
  • Publication number: 20040207017
    Abstract: It is an object to provide a semiconductor device having an SOI structure in which an electric potential of a body region in an element formation region isolated by a partial isolation region can be fixed with a high stability. A MOS transistor comprising a source region (51), a drain region (61) and an H gate electrode (71) is formed in an element formation region isolated by a partial oxide film (31). The H gate electrode (71) electrically isolates a body region (13) formed in a gate width W direction adjacently to the source region (51) and the drain region (61) from the drain region (61) and the source region (51) through “I” in a transverse direction (a vertical direction in the drawing), a central “-” functions as a gate electrode of an original MOS transistor.
    Type: Application
    Filed: May 10, 2004
    Publication date: October 21, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Shigenobu Maeda, Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6806537
    Abstract: A semiconductor device which achieves reductions in malfunctions and operating characteristic variations by reducing the gain of a parasitic bipolar transistor, and a method of manufacturing the same are provided. A silicon oxide film (6) is formed partially on the upper surface of a silicon layer (3). A gate electrode (7) of polysilicon is formed partially on the silicon oxide film (6). A portion of the silicon oxide film (6) underlying the gate electrode (7) functions as a gate insulation film. A silicon nitride film (9) is formed on each side surface of the gate electrode (7), with a silicon oxide film (8) therebetween. The silicon oxide film (8) and the silicon nitride film (9) are formed on the silicon oxide film (6). The width (W1) of the silicon oxide film (8) in a direction of the gate length is greater than the thickness (T1) of the silicon oxide film (6).
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: October 19, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Hirokazu Sayama, Shigenobu Maeda, Toshiaki Iwamatsu, Kazunobu Ota
  • Patent number: 6798021
    Abstract: By ion implantation process, a P-type impurity for element isolation is implanted at an impurity concentration (P1) into a silicon layer (3) defined between the bottom surface of an element isolation insulating film (5a) and the upper surface of a BOX layer (2). Resulting from this implantation, a P-type impurity is implanted at an impurity concentration (P2) into the silicon layer (3) under a gate oxide film (7a) and in the vicinity of an interface between the silicon layer (3) and the BOX layer (2). Under a capacitor dielectric film (7b) and in the vicinity of an interface between the silicon layer (3) and the BOX layer (2), the silicon layer (3) has an impurity concentration (P0) which is the initial concentration of itself.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: September 28, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu
  • Patent number: 6794717
    Abstract: It is an object to provide a semiconductor device having an SOI structure in which an electric potential of a body region in an element formation region isolated by a partial isolation region can be fixed with a high stability. A MOS transistor comprising a source region (51), a drain region (61) and an H gate electrode (71) is formed in an element formation region isolated by a partial oxide film (31). The H gate electrode (71) electrically isolates a body region (13) formed in a gate width W direction adjacently to the source region (51) and the drain region (61) from the drain region (61) and the source region (51) through “I” in a transverse direction (a vertical direction in the drawing), a central “-” functions as a gate electrode of an original MOS transistor.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: September 21, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Shigenobu Maeda, Toshiaki Iwamatsu, Takashi Ipposhi
  • Publication number: 20040164353
    Abstract: In a semiconductor device having an SOI structure and a method of manufacturing the same, influence by a parasitic transistor can be prevented, and no disadvantage is caused in connection with a manufacturing process. In this semiconductor device, an upper side portion of a semiconductor layer is rounded. Thereby, concentration of an electric field at the upper side portion of the semiconductor layer can be prevented. As a result, lowering of a threshold voltage of a parasitic transistor can be prevented, so that the parasitic transistor does not adversely affect subthreshold characteristics of a regular transistor. Owing to provision of a concavity of a U-shaped section, generation of etching residue can be prevented when etching a gate electrode for patterning the same. Thereby, a disadvantage is not caused in connection with the manufacturing process.
    Type: Application
    Filed: October 10, 2003
    Publication date: August 26, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Toshiaki Iwamatsu, Yasuo Yamaguchi, Shigenobu Maeda, Shoichi Miyamoto, Akihiko Furukawa, Yasuo Inoue
  • Patent number: 6774435
    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: Grant
    Filed: November 24, 1999
    Date of Patent: August 10, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takuji Matsumoto, Toshiaki Iwamatsu
  • Publication number: 20040150047
    Abstract: In formation of a source/drain region of an NMOS transistor, a gate-directional extension region <41a> of an N+ block region <41> in an N+ block resist film <51> prevents a well region <11> located under the gate-directional extension region <41a> from implantation of an N-type impurity. A high resistance forming region, which is the well region <11> having a possibility for implantation of an N-type impurity on a longitudinal extension of a gate electrode <9>, can be formed as a high resistance forming region <A2> narrower than a conventional high resistance forming region <A1>. Thus, a semiconductor device having a partially isolated body fixed SOI structure capable of reducing body resistance and a method of manufacturing the same are obtained.
    Type: Application
    Filed: December 31, 2003
    Publication date: August 5, 2004
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Shigenobu Maeda, Toshiaki Iwamatsu, Takashi Ipposhi
  • Publication number: 20040135211
    Abstract: According to a semiconductor device of the present invention, a field oxide film is formed so as to cover the main surface of an SOI layer and to reach the main surface of a buried oxide film. As a result, a pMOS active region of the SOI and an nMOS active region of the SOI can be electrically isolated completely. Therefore, latchup can be prevented completely. As a result, it is possible to provide a semiconductor device using an SOI substrate which can implement high integration by eliminating reduction of the breakdown voltage between source and drain, which was a problem of a conventional SOI field effect transistor, as well as by efficiently disposing a body contact region, which hampers high integration, and a method of manufacturing the same.
    Type: Application
    Filed: December 24, 2003
    Publication date: July 15, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yasuo Inoue, Tadashi Nishimura, Yasuo Yamaguchi, Toshiaki Iwamatsu
  • Publication number: 20040119133
    Abstract: A semiconductor device which enables an improvement of a current driving capability of a MOS transistor sufficiently is attained.
    Type: Application
    Filed: April 4, 2003
    Publication date: June 24, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Toshiaki Iwamatsu
  • Publication number: 20040115905
    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:
    Type: Application
    Filed: December 13, 2002
    Publication date: June 17, 2004
    Inventors: Thierry Barge, Bruno Ghyselen, Toshiaki Iwamatsu, Hideki Naruoka, Junichiro Furihata, Kiyoshi Mitani
  • Publication number: 20040094803
    Abstract: Formed on an insulator (9) are an N− type semiconductor layer (10) having a partial isolator formed on its surface and a P− type semiconductor layer (20) having a partial isolator formed on its surface. Source/drain (11, 12) being P+ type semiconductor layers are provided on the semiconductor layer (10) to form a PMOS transistor (1). Source/drain (21, 22) being N+ type semiconductor layers are provided on the semiconductor layer (20) to form an NMOS transistor (2). A pn junction (J5) formed by the semiconductor layers (10, 20) is provided in a CMOS transistor (100) made up of the transistors (1, 2). The pn junction (J5) is positioned separately from the partial isolators (41, 42), where the crystal defect is thus very small. Therefore, the leakage current is very low at the pn junction (J5).
    Type: Application
    Filed: November 17, 2003
    Publication date: May 20, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu
  • Patent number: 6727572
    Abstract: A semiconductor device with a spiral inductor is provided, which determines the area of an insulation layer to be provided in the surface of a wiring board thereunder. A trench isolation oxide film, which is a complete isolation oxide film including in part the structure of a partial isolation oxide film, is provided in a larger area of the surface of an SOI layer than that corresponding to the area of a spiral inductor. The trench isolation oxide film includes a first portion having a first width and extending in a direction approximately perpendicular the surface of a buried oxide film, and a second portion having a second width smaller than the first width and being continuously formed under the first portion, extending approximately perpendicular to the surface of the buried oxide film. The trench isolation oxide film is provided such that a horizontal distance between each end surface of the second portion and a corresponding end surface of the spiral inductor makes a predetermined distance or more.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: April 27, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Shigenobu Maeda, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu
  • Patent number: 6727552
    Abstract: According to a semiconductor device of the present invention, a field oxide film is formed so as to cover the main surface of an SOI layer and to reach the main surface of a buried oxide film. As a result, a pMOS active region of the SOI and an nMOS active region of the SOI can be electrically isolated completely. Therefore, latchup can be prevented completely. As a result, it is possible to provide a semiconductor device using an SOI substrate which can implement high integration by eliminating reduction of the breakdown voltage between source and drain, which was a problem of a conventional SOI field effect transistor, as well as by efficiently disposing a body contact region, which hampers high integration, and a method of manufacturing the same.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: April 27, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuo Inoue, Tadashi Nishimura, Yasuo Yamaguchi, Toshiaki Iwamatsu
  • Publication number: 20040061200
    Abstract: A semiconductor wafer and its manufacturing method are provided where the current driving capability of a MOS transistor can be sufficiently enhanced. An SOI layer wafer in which an SOI layer (32) is formed has a <100> crystal direction notch (32a) and a <110> crystal direction notch (32b). The SOI layer wafer and a supporting substrate wafer (1) are bonded to each other in such a way that the notch (32a) and a <110> crystal direction notch (1a) of the supporting substrate wafer (1) coincide with each other. When bonding the two wafers by using the notch (32a) and the notch (1a) to position the two wafers, the other notch (32b) of the SOI layer wafer can be engaged with a guide member of the semiconductor wafer manufacturing apparatus to prevent positioning error due to relative turn between the wafers.
    Type: Application
    Filed: June 16, 2003
    Publication date: April 1, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Toshiaki Iwamatsu, Shigenobu Maeda
  • Patent number: 6707105
    Abstract: Formed on an insulator (9) are an N− type semiconductor layer (10) having a partial isolator formed on its surface and a P− type semiconductor layer (20) having a partial isolator formed on its surface. Source/drain (11, 12) being P+ type semiconductor layers are provided on the semiconductor layer (10) to form a PMOS transistor (1). Source/drain (21, 22) being N+ type semiconductor layers are provided on the semiconductor layer (20) to form an NMOS transistor (2). A pn junction (J5) formed by the semiconductor layers (10, 20) is provided in a CMOS transistor (100) made up of the transistors (1, 2). The pn junction (J5) is positioned separately from the partial isolators (41, 42), where the crystal defect is thus very small. Therefore, the leakage current is very low at the pn junction (J5).
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: March 16, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu
  • Publication number: 20040046216
    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: September 9, 2003
    Publication date: March 11, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Hideki Naruoka, Nobuyoshi Hattori, Shigeto Maegawa, Yasuo Yamaguchi, Takuji Matsumoto
  • Patent number: 6693324
    Abstract: A semiconductor layer has one end placed on top of a first conductive layer and in contact with the first conductive layer, and the other end placed on top of a second conductive layer and in contact with the second conductive layer. At the central portion, the semiconductor layer faces a gate electrode layer with a gate insulating layer interposed therebetween. The semiconductor layer is formed so that its width W1 is smaller than its height H1. As a result, a thin film transistor and manufacturing method thereof can be obtained in which contact between a source/drain region of the thin film transistor and an upper or lower conductive layer can be made stably.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: February 17, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu
  • Publication number: 20030218213
    Abstract: By ion implantation process, a P-type impurity for element isolation is implanted at an impurity concentration (P1) into a silicon layer (3) defined between the bottom surface of an element isolation insulating film (5a) and the upper surface of a BOX layer (2). Resulting from this implantation, a P-type impurity is implanted at an impurity concentration (P2) into the silicon layer (3) under a gate oxide film (7a) and in the vicinity of an interface between the silicon layer (3) and the BOX layer (2). Under a capacitor dielectric film (7b) and in the vicinity of an interface between the silicon layer (3) and the BOX layer (2), the silicon layer (3) has an impurity concentration (P0) which is the initial concentration of itself.
    Type: Application
    Filed: November 12, 2002
    Publication date: November 27, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu