Patents by Inventor Shigenobu Maeda

Shigenobu Maeda 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: 6858918
    Abstract: It is an object to obtain a semiconductor device including a capacitance having a great Q-value. In an SOI substrate comprising a support substrate (165), a buried oxide film (166) and an SOI layer (171), an isolating oxide film 167 (167a to 167c) is selectively formed in an upper layer portion of the SOI layer (171) with a part of the SOI layer (171) remaining as a P? well region (169). Consequently, an isolation (partial isolation) structure is obtained. An N+ diffusion region (168) is formed in the SOI layer (171) between the isolating oxide films (167a) and (167b) and a P+ diffusion region (170) is formed in the SOI layer (171) between the isolating oxide films (167b) and (167c). Consequently, there is obtained a junction type variable capacitance (C23) having a PN junction surface of the P? well region (169) provided under the isolating oxide film (167b) and the N+ diffusion region (168).
    Type: Grant
    Filed: August 13, 2002
    Date of Patent: February 22, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Shigenobu Maeda, Takashi Ipposhi, 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
  • Publication number: 20050017836
    Abstract: An on-chip inductor includes a main inductor portion configured to provide a main magnetic field of an on-chip inductor. An interconnect inductor portion is electrically coupled to the main inductor portion and is configured to provide an interconnect magnetic field that constructively combines with the main magnetic field.
    Type: Application
    Filed: May 5, 2004
    Publication date: January 27, 2005
    Inventors: Shigenobu Maeda, Jeong-hwan Yang
  • 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: 20040232554
    Abstract: The semiconductor device has a silicon layer (SOI layer) (12) formed through a silicon oxide film (11) on a support substrate (10). A transistor (T1) is formed in the SOI layer (12). The wiring (17a) is connected with a source of the transistor (T1) through a contact plug (15a). A back metal (18) is formed on an under surface (back surface) of the support substrate (10) and said back metal (18) is connected with the wiring (17a) through a heat radiating plug (16). The contact plug (15a), the heat radiating plug (16) the wiring (17a) and the back metal (18) is made of a metal such as aluminum, tungsten and so on which has a higher thermal conductivity than that of the silicon oxide film (11) and the support substrate (10).
    Type: Application
    Filed: March 8, 2004
    Publication date: November 25, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Yuuichi Hirano, Shigenobu Maeda, Takuji Matsumoto, Takashi Ipposhi, Shigeto Maegawa
  • 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
  • Patent number: 6815295
    Abstract: In a semiconductor device and a method of manufacturing the same according to the present invention, a trade-off relationship between threshold values and a diffusion layer leakage is eliminated and it is not necessary to form gate oxide films at more than one stages. Since doses of nitrogen are different from each other between gate electrodes (4A to 4C) of N-channel type MOS transistors (T41 to T43), concentrations of nitrogen in the nitrogen-introduced regions (N1 to N3) are accordingly different from each other. Concentrations of nitrogen in the gate electrodes are progressively lower in the order of expected higher threshold values.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: November 9, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Shuichi Ueno, Yoshinori Okumura, Shigenobu Maeda, Shigeto Maegawa
  • 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: 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: 20040174756
    Abstract: A plurality of word lines (WL1) are provided in parallel to one another and a plurality of bit lines (BL1) are provided in parallel to one another, intersecting the word lines (WL1) thereabove. MRAM cells (MC2) are formed at intersections of the word lines and the bit lines therebetween. MRAM cells (MC3) are provided so that an easy axis indicated by the arrow has an angle of 45 degrees with respect to the bit lines and the word lines. Thus, an MRAM capable of cutting the power consumption in writing is achieved and further an MRAM capable of reducing the time required for erasing and writing operations is achieved.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 9, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Tatsuya Kunikiyo, Katsumi Eikyu, Shigenobu Maeda
  • Patent number: 6787855
    Abstract: A semiconductor device and a manufacturing method thereof are obtained which can restrain increase of the parasitic capacitance generated between contact plugs of source/drain regions and a gate electrode while reducing the area of the source/drain regions. A channel region is formed under a gate electrode 1. A pair of source/drain regions 2 are formed to sandwich the channel region. The source/drain regions 2 have a first part 3a being adjacent to the channel region and a second part 3b formed to protrude in a channel width direction from the first part 3a so that a part of outer peripheries of the source/drain regions 2 extend away from the gate electrode 1 in a plan view. Contact plugs 4 are formed on the second part 3b for connecting the source/drain regions 2 to source/drain wirings.
    Type: Grant
    Filed: February 7, 2001
    Date of Patent: September 7, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Yuuichi Hirano, Shigenobu Maeda, Shigeto Maegawa
  • 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: 6777283
    Abstract: Provided are a semiconductor device that optimizes the operation characteristics such as of both an insulating gate type transistor for high voltage and an insulating gate type transistor for low voltage, and a method of manufacturing the same. Specifically, a patterned resist is formed so as to cover a low voltage operation region, a second LDD implantation process of implanting an impurity ion by using the resist as a mask, is performed over a silicon oxide film thereby to form an impurity diffusion region in the surface of a semiconductor substrate in a high voltage operation region. After this step, the silicon oxide film in the high voltage operation region contains the impurity during the second LDD implantation process whereas the silicon oxide film in a low voltage operation region contains no impurity.
    Type: Grant
    Filed: November 15, 2002
    Date of Patent: August 17, 2004
    Assignee: Renesas Technology Corp.
    Inventor: Shigenobu Maeda
  • 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: 20040145017
    Abstract: A semiconductor device and a manufacturing method thereof are obtained which can restrain increase of the parasitic capacitance generated between contact plugs of source/drain regions and a gate electrode while reducing the area of the source/drain regions. A channel region is formed under a gate electrode 1. A pair of source/drain regions 2 are formed to sandwich the channel region. The source/drain regions 2 have a first part 3a being adjacent to the channel region and a second part 3b formed to protrude in a channel width direction from the first part 3a so that a part of outer peripheries of the source/drain regions 2 extend away from the gate electrode 1 in a plan view. Contact plugs 4 are formed on the second part 3b for connecting the source/drain regions 2 to source/drain wirings.
    Type: Application
    Filed: January 15, 2004
    Publication date: July 29, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Yuuichi Hirano, Shigenobu Maeda, Shigeto Maegawa
  • Patent number: 6741495
    Abstract: A plurality of word lines (WL1) are provided in parallel to one another and a plurality of bit lines (BL1) are provided in parallel to one another, intersecting the word lines (WL1) thereabove. MRAM cells (MC2) are formed at intersections of the word lines and the bit lines therebetween. MRAM cells (MC3) are provided so that an easy axis indicated by the arrow has an angle of 45 degrees with respect to the bit lines and the word lines. Thus, an MRAM capable of cutting the power consumption in writing is achieved and further an MRAM capable of reducing the time required for erasing and writing operations is achieved.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: May 25, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tatsuya Kunikiyo, Katsumi Eikyu, Shigenobu Maeda
  • 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
  • Publication number: 20040075141
    Abstract: There is provided a semiconductor device which is formed on a semiconductor substrate and allows effective use of the feature of the semiconductor substrate, and there is also provided a method of manufacturing the same. An N-channel MOS transistor including a P-type body layer (3a), and a P-type active layer (6) for body voltage application which is in contact with the P-type body layer (3a) are formed on an SOI substrate which is formed to align a <110> crystal direction of a support substrate (1) with a <100> crystal direction of an SOI layer (3). A path connecting the P-type body layer (3a) and the P-type active layer (6) for body voltage application is aligned parallel to the <100> crystal direction of the SOI layer (3). Since hole mobility is higher in the <100> crystal direction, parasitic resistance (Ra, Rb) can be reduced in the above path. This speeds up voltage transmission to the P-type body layer (3a) and improves voltage fixing capability in the P-type body layer (3a).
    Type: Application
    Filed: June 12, 2003
    Publication date: April 22, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Shigenobu Maeda, Shigeto Maegawa, Takuji Matsumoto
  • 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