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: 6649976
    Abstract: A semiconductor device in which parasitic resistance of source/drain regions can be reduced than the parasitic resistance of the drain region, and manufacturing method thereof, can be obtained. In the semiconductor device, inactivating ions are implanted only to the source region of the semiconductor layer, so as to damage the crystal near the surface of the semiconductor layer, whereby siliciding reaction is promoted. Therefore, in the source region, a titanium silicide film which is thicker can be formed.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: November 18, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Yasuo Inoue, Yasuo Yamaguchi, Tadashi Nishimura
  • Patent number: 6646306
    Abstract: A semiconductor device that prevents 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, a polysilicon film selectively provided on the trench isolation oxide film, a silicon layer provided on the polysilicon film, and a side wall spacer provided on a side surface of the polysilicon film. The polysilicon film is provided in a position corresponding to a top of a PN junction portion JP of a P-type well region and an N-type well region in a SOI layer across the two well regions.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: November 11, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Hideki Naruoka, Nobuyoshi Hattori, Shigeto Maegawa, Yasuo Yamaguchi, Takuji Matsumoto
  • Publication number: 20030207548
    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: Application
    Filed: April 28, 2003
    Publication date: November 6, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA, Tokyo, Japan
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu, Yasuo Yamaguchi
  • Publication number: 20030201494
    Abstract: It is an object to provide an SOI device capable of carrying out body fixation and implementing a quick and stable operation. A gate insulating film (11) having a thickness of 1 to 5 nm is provided between a portion other than a gate contact pad (GP) of a gate electrode (12) and an SOI layer (3), and a gate insulating film (110) having a thickness of 5 to 15 nm is provided between the gate contact pad (GP) and the SOI layer (3). The gate insulating film (11) and the gate insulating film (110) are provided continuously.
    Type: Application
    Filed: October 2, 2002
    Publication date: October 30, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shigenobu Maeda, Takuji Matsumoto, Toshiaki Iwamatsu, Takashi Ipposhi
  • Publication number: 20030197223
    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: Application
    Filed: May 8, 2003
    Publication date: October 23, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shoichi Miyamoto, Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6627512
    Abstract: In a combined isolation oxide film (BT1), a part closer to a gate electrode (GT13) reaches a buried oxide film (2) through an SOI layer (3) while a part closer to another gate electrode (GT12) has a sectional shape provided with a well region on its lower portion. The shape of an edge portion of the combined isolation oxide film (BT1) is in the form of a bird's beak in a LOCOS isolation oxide film. Consequently, the thicknesses of portions defining edge portions of the gate oxide films (GO12, GO13) are locally increased. Thus provided are a semiconductor device including a MOS transistor having a gate oxide film prevented from dielectric breakdown without increasing its thickness and a method of manufacturing the same.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: September 30, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Takuji Matsumoto
  • Publication number: 20030153136
    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: August 12, 2002
    Publication date: August 14, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Takuji Matsumoto, Mikio Tsujiuchi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Shigeto Maegawa
  • Publication number: 20030148595
    Abstract: An object is to provide a semiconductor substrate processing method and a semiconductor substrate that prevent formation of particles from the edge part of the substrate. Silicon ions are implanted into the edge part of an SOI substrate (10) in the direction of radiuses of the SOI substrate (10) to bring a buried oxide film (2) in the edge part of the SOI substrate (10) into a silicon-rich state. Thus an SOI substrate (100) is provided, where the buried oxide film (2) has substantially been eliminated in the edge part.
    Type: Application
    Filed: February 4, 2003
    Publication date: August 7, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yoshiko Yoshida, Hideki Naruoka, Yasuhiro Kimura, Yasuo Yamaguchi, Toshiaki Iwamatsu, Yuuichi Hirano
  • Patent number: 6596615
    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: January 12, 2000
    Date of Patent: July 22, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Ipposhi, Toshiaki Iwamatsu, Yasuo Yamaguchi
  • Patent number: 6586802
    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: July 2, 1999
    Date of Patent: July 1, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shoichi Miyamoto, Toshiaki Iwamatsu, Takashi Ipposhi
  • Publication number: 20030119245
    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 (RM12) is formed so as to have an opening over a region (PR) in which a PMOS transistor is formed. Channel stop implantation is performed with energy by which ions pass through a partial isolation oxide film (PT11) and a peak of an impurity profile is generated in an SOI layer (3), thereby forming a channel stop layer (N1) in the SOI layer (3) under the partial isolation oxide film (PT11), 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 (N1) is set to 1×1017 to 1x1019/cm3.
    Type: Application
    Filed: September 9, 2002
    Publication date: June 26, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Toshiaki Iwamatsu, Takashi Ipposhi, Takuji Matsumoto, Shigenobu Maeda
  • Publication number: 20030107038
    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: January 6, 2003
    Publication date: June 12, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Yasuo Yamaguchi, Shigenobu Maeda, Shoichi Miyamoto, Akihiko Furukawa, Yasuo Inoue
  • Publication number: 20030102521
    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 (19), 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 (3) than that corresponding to the area of a spiral inductor (SI). The trench isolation oxide film (19) is comprised of a first portion (191) having a first width and extending in a direction approximately perpendicular the surface of a buried oxide film (2), and a second portion (192) having a second width smaller than the first width and being continuously formed under the first portion (191), extending approximately perpendicular to the surface of the buried oxide film (2).
    Type: Application
    Filed: January 13, 2003
    Publication date: June 5, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shigenobu Maeda, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu
  • Patent number: 6563172
    Abstract: An object is to provide a semiconductor substrate processing method and a semiconductor substrate that prevent formation of particles from the edge part of the substrate. Silicon ions are implanted into the edge part of an SOI substrate (10) in the direction of radiuses of the SOI substrate (10) to bring a buried oxide film (2) in the edge part of the SOI substrate (10) into a silicon-rich state. Thus an SOI substrate (100) is provided, where the buried oxide film (2) has substantially been eliminated in the edge part.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: May 13, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshiko Yoshida, Hideki Naruoka, Yasuhiro Kimura, Yasuo Yamaguchi, Toshiaki Iwamatsu, Yuuichi Hirano
  • Patent number: 6558990
    Abstract: A manufacturing method of a SOI substrate (10) comprises the steps of: forming an oxide film (12) at cross-sectional both main surfaces and cross-sectional both end surfaces of a silicon substrate (11); forming a resist layer (13) on the oxide film (12) at cross-sectional both end surfaces of the substrate (11); and removing the oxide film (12) at those portions which are left from the covering of the resist layer (13), to thereby expose the both main surfaces of the substrate (11). Next, the resist layer (13) is removed to thereby leave the oxide film (12) at the both end surfaces of the substrate (11); and oxygen ions (I) are dosed into the substrate (11) from one of the exposed both main surfaces, followed by an anneal processing to thereby form an oxide layer (14) in a region at a predetermined depth from the one main surface of the substrate (11). The oxide film (12) left on the both end surfaces of the substrate (11) is then removed.
    Type: Grant
    Filed: March 1, 2001
    Date of Patent: May 6, 2003
    Assignees: Mitsubishi Materials Silicon Corporation, Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masaru Takamatsu, Takashi Katakura, Toshiaki Iwamatsu, Hideki Naruoka
  • Patent number: 6541841
    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 is comprised of 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.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: April 1, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu
  • Publication number: 20030052325
    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: Application
    Filed: July 2, 1999
    Publication date: March 20, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: SHOICHI MIYAMOTO, TOSHIAKI IWAMATSU, TAKASHI IPPOSHI
  • Publication number: 20030042542
    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: Application
    Filed: September 6, 1996
    Publication date: March 6, 2003
    Inventors: SHIGETO MAEGAWA, TAKASHI IPPOSHI, TOSHIAKI IWAMATSU
  • Publication number: 20030025135
    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: July 11, 2002
    Publication date: February 6, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Takuji Matsumoto, Hirokazu Sayama, Shigenobu Maeda, Toshiaki Iwamatsu, Kazunobu Ota
  • Patent number: 6509583
    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: Grant
    Filed: October 3, 2000
    Date of Patent: January 21, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiaki Iwamatsu, Yasuo Yamaguchi, Shigenobu Maeda, Shoichi Miyamoto, Akihiko Furukawa, Yasuo Inoue