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: 6465832
    Abstract: A small-sized low-power-loss capacitor having low parasitic resistance is obtained by adopting metal wires as wires in a line and space structure to utilize capacitances between adjacent metal wires. A plurality of wires (3) each extending in a direction (x) and composed of metals such as Al and Cu are aligned in a direction (y) at predetermined intervals, forming a line and space structure (4). The line and space structure (4) is formed on a silicon substrate (1). On the silicon substrate (1), an insulation film (2) composed for example of a silicon oxide film is formed to provide electrical isolation between adjacent wires (3).
    Type: Grant
    Filed: April 5, 2000
    Date of Patent: October 15, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Kazuya Yamamoto
  • Patent number: 6465292
    Abstract: An SOI layer is formed on a silicon substrate with a buried insulating layer therebetween. An SOI-MOSFET is formed including a drain region and a source region that are formed to define a channel formation region at the SOI layer and including a gate electrode layer opposite to the channel formation region with an insulating layer therebetween. An FS isolation structure is formed to have an FS plate opposite to a region of the SOI layer in the vicinity of the edge portion of the drain region and the source region, and to electrically isolate the SOI-MOSFET from other elements by applying a prescribed potential to the FS plate to fix the potential of the region of the SOI layer opposite to the FS plate. The channel formation region includes two edge portions on both sides and a central portion between the edge portions in a direction of a channel width, and a channel length at the edge of a prescribed region is smaller than a channel length at the central portion.
    Type: Grant
    Filed: February 4, 2002
    Date of Patent: October 15, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Toshiaki Iwamatsu
  • Publication number: 20020145902
    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: November 21, 2001
    Publication date: October 10, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tatsuya Kunikiyo, Katsumi Eikyu, Shigenobu Maeda
  • Patent number: 6459125
    Abstract: A semiconductor device for CSP mounting which avoids errors due to alpha rays and is highly stress-resistant is provided. A buried oxide film (107) is formed on a semiconductor substrate (101), and a MOS transistor having an SOI structure is formed on the buried oxide film (107). The MOS transistor comprises source and drain regions (120a, 120b) formed in a semiconductor layer (120), and a gate electrode (110). An aluminum pad (103) connected to any one of the source and drain regions (120a, 120b) through a connecting mechanism not shown, and a silicon nitride film (104) having an opening on the top of the aluminum pad (103) are formed on an interlayer insulation film (108). A layer of titanium (105) and a layer of nickel (106) are formed extending from the aluminum pad (103) to an end of the silicon nitride film (104). A solder bump (11) is disposed on the layer of nickel (106).
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: October 1, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Tadashi Nishimura, Kazuhito Tsutsumi, Shigeto Maegawa, Yuuichi Hirano
  • Publication number: 20020130374
    Abstract: According to a semiconductor device and a method of manufacturing the same, a trade-off relationship between threshold values and a diffusion layer leak is eliminated and it is not necessary to form gate oxide films at more than one stages. Since impurity dose are different from each other between gate electrodes (4A to 4C) of N-channel type MOS transistors (T41 to T43), impurity concentration in the gate electrodes (4A to 4C) are different from each other. The impurity concentration in the gate electrodes are progressively lower in the order of higher threshold values which are expected.
    Type: Application
    Filed: August 4, 1999
    Publication date: September 19, 2002
    Inventors: SHUICHI UENO, YOSHINORI OKUMURA, SHIGENOBU MAEDA, SHIGETO MAEGAWA
  • Patent number: 6452249
    Abstract: A semiconductor device having an inductor is provided. In an RF circuit portion (RP), a region in an SOI layer (3) corresponding to a region in which a spiral inductor (SI) is provided is divided into a plurality of SOI regions (21) by a plurality of trench isolation oxide films (11). The trench isolation oxide films (11) are formed by filling trenches extending from the surface of the SOI layer (3) to the surface of a buried oxide film (2) with a silicon oxide film, and completely electrically isolate the SOI regions (21) from each other. The trench isolation oxide films (11) have a predetermined width and are shaped to extend substantially perpendicularly to the surface of the buried oxide film (2). The semiconductor device is capable of reducing electrostatically induced power dissipation and electromagnetically induced power dissipation, and preventing the structure and manufacturing steps thereof from becoming complicated.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: September 17, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Yuuichi Hirano, Takashi Ipposhi, Takuji Matsumoto
  • Patent number: 6441448
    Abstract: A memory cell which is capable of reducing the memory cell size in SRAM using a field-shield isolation on an SOI substrate. An isolation oxide film is provided between a field-shield isolation plate for n-type transistors and a field-shield isolation plate for p-type transistors.
    Type: Grant
    Filed: April 12, 1999
    Date of Patent: August 27, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Hirotada Kuriyama
  • Patent number: 6436792
    Abstract: A silicon oxide film (6aa) is formed on an upper surface of an SOI layer (3), a silicon nitride film (6bb) is formed on the silicon oxide film (6aa), and a silicon oxide film (6cc) is formed on the silicon nitride film (6bb). Using the silicon nitride film (6bb) as an etch stopper, anisotropic dry etching is performed on the silicon oxide film (6cc) in first and second device formation regions. Then, using the silicon oxide film (6aa) as an etch stopper, anisotropic dry etching is performed on the silicon nitride film (6bb) in the first and second device formation regions. The silicon oxide film (6aa) in the first and second device formation regions is removed by wet etching using hydrofluoric acid to expose the upper surface of the SOI layer (3). A method of manufacturing a semiconductor device is provided which is capable of avoiding the formation of a damaged layer in a main surface of an SOI substrate when such a device isolation structure is formed.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: August 20, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuo Yamaguchi, Shigenobu Maeda, Yuuichi Hirano
  • Publication number: 20020110954
    Abstract: A semiconductor device for CSP mounting which avoids errors due to alpha rays and is highly stress-resistant is provided. A buried oxide film (107) is formed on a semiconductor substrate (101), and a MOS transistor having an SOI structure is formed on the buried oxide film (107). The MOS transistor comprises source and drain regions (120a, 120b) formed in a semiconductor layer (120), and a gate electrode (110). An aluminum pad (103) connected to any one of the source and drain regions (120a, 120b) through a connecting mechanism not shown, and a silicon nitride film (104) having an opening on the top of the aluminum pad (103) are formed on an interlayer insulation film (108). A layer of titanium (105) and a layer of nickel (106) are formed extending from the aluminum pad (103) to an end of the silicon nitride film (104). A solder bump (11) is disposed on the layer of nickel (106).
    Type: Application
    Filed: April 16, 2002
    Publication date: August 15, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shigenobu Maeda, Tadashi Nishimura, Kazuhito Tsutsumi, Shigeto Maegawa, Yuuichi Hirano
  • Publication number: 20020110936
    Abstract: An inductor recognition method for recognizing an inductor, a layout inspection method wherein it is possible to automatically carry out a verification of a design standard, in the inductor and a process for a semiconductor device using this layout inspection method are provided. The inductor recognition method includes the step of arranging an inductor position representation mark so as to surround a design pattern of an interconnection part, which works as an inductor and has a starting point and a finishing point; the step of arranging a starting point position representation mark and a finishing point position representation mark so as to surround, respectively, regions corresponding to the starting point and the finishing point; and the step of recognizing information with respect to an inductor by means of the inductor position representation mark, the starting point position representation mark and the finishing point position representation mark.
    Type: Application
    Filed: September 14, 2001
    Publication date: August 15, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshiki Wada, Hiroshi Komurasaki, Shigenobu Maeda, Shuji Yoshida
  • Publication number: 20020110989
    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: April 12, 2002
    Publication date: August 15, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yasuo Yamaguchi, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu, Shigenobu Maeda, Yuuichi Hirano, Takuji Matsumoto, Shoichi Miyamoto
  • Publication number: 20020109187
    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: November 7, 2001
    Publication date: August 15, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Takuji Matsumoto, Shigenobu Maeda, Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6429079
    Abstract: Provided is a semiconductor device with a silicide protection structure that prevents the over-etching of a source/drain layer in forming a contact hole and prevents a voltage drop in surge voltage without increasing the area of the source/drain layer, as well as a manufacturing method of the device. There is defined an active region (AR) of an MOS transistor and a gate electrode (10) that constitutes a field-shield isolation structure formed in a rectangular loop shape. Over the FS gate electrode (10) and the active region (AR), a gate electrode (20) of the MOS transistor is formed so as to divide the FS gate electrode (10) in two. Each of the active regions (AR) facing each other across the gate electrode (20) has a silicide protection structure (PS1), whose surrounding is an S/D layer (30), and a silicide film (SF1) is formed over the structure (PS1).
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: August 6, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yuuichi Hirano
  • Publication number: 20020100286
    Abstract: A freezer (106) is provided with a connector (120) and connected to a semiconductor equipment (10). The connector (120) may include a connector for power supply (120a), a connector for data communication (120b) and a connector for analog signal (120c). Therefore, the semiconductor equipment (10) can transmit data and signal to the outside while being cooled in the freezer (106). With this constitution, a semiconductor equipment housed in a cooling system for high-speed operation and a refrigerator for cooling the semiconductor equipment are provided.
    Type: Application
    Filed: December 17, 1999
    Publication date: August 1, 2002
    Inventor: SHIGENOBU MAEDA
  • Patent number: 6426543
    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: November 22, 2000
    Date of Patent: July 30, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Shigeto Maegawa, Takashi Ipposhi, Toshiaki Iwamatsu
  • Patent number: 6424010
    Abstract: An SOI layer is formed on a silicon substrate with a buried insulating layer therebetween. An SOI-MOSFET is formed including a drain region and a source region that are formed to define a channel formation region at the SOI layer and including a gate electrode layer opposite to the channel formation region with an insulating layer therebetween. A field-shield (FS) isolation structure is formed to have an FS plate opposite to a region of the SOI layer in the vicinity of the edge portion of the drain region and the source region, and to electrically isolate the SOI-MOSFET from other elements by applying a prescribed potential to the FS plate to fix the potential of the region of the SOI layer opposite to the FS plate. The channel formation region includes the edge portions on both sides and a central portion between the edge portions in a direction of a channel width, and a channel length at the edge of prescribed region is smaller than a channel length at the central portion.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: July 23, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Toshiaki Iwamatsu
  • Publication number: 20020094614
    Abstract: An SOI layer is formed on a silicon substrate with a buried insulating layer therebetween. An SOI-MOSFET is formed including a drain region and a source region that are formed to define a channel formation region at the SOI layer and including a gate electrode layer opposite to the channel formation region with an insulating layer therebetween. An FS isolation structure is formed to have an FS plate opposite to a region of the SOI layer in the vicinity of the edge portion of the drain region and the source region, and to electrically isolate the SOI-MOSFET from other elements by applying a prescribed potential to the FS plate to fix the potential of the region of the SOI layer opposite to the FS plate. The channel formation region includes two edge portions on both sides and a central portion between the edge portions in a direction of a channel width, and a channel length at the edge of a prescribed region is smaller than a channel length at the central portion.
    Type: Application
    Filed: February 4, 2002
    Publication date: July 18, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Toshiaki Iwamatsu
  • Patent number: 6420751
    Abstract: A field effect transistor occupying a small area and a semiconductor device using the same can be obtained. A gate electrode is provided on a substrate on which a source region is provided with a first interlayer insulating film interposed therebetween. The gate electrode is covered with a second interlayer insulating film. A contact hole for exposing a part of the surface of the source region is provided so as to penetrate through the first interlayer insulating film, the gate electrode, and the second interlayer insulating film. A sidewall surface of the contact hole is covered with a gate insulating film. A first semiconductor layer of a first conductivity type is provided on the surface of the source region in contact therewith up to the lower surface of the gate electrode. A channel semiconductor layer is provided on the surface of the first semiconductor layer up to the upper surface of the gate electrode.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: July 16, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Yasuo Yamaguchi, Hirotada Kuriyama, Shigeto Maegawa
  • Publication number: 20020090764
    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: November 20, 2001
    Publication date: July 11, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Toshiaki Iwamatsu, Takashi Ipposhi
  • Patent number: 6414353
    Abstract: An SOI layer is formed so thick that a body region is not fully depleted under conditions of floating and a zero potential. When a MOSFET operates, a negative body potential is applied to the body region through a body electrode. Thus, the body region is fully depleted. The MOSFET is formed equivalently to a conventional MOSFET of a PD mode as to the thickness of the SOI layer, and is equivalent to a MOSFET of an FD mode as to its operation. Therefore, both of advantages of a PD mode MOSFET such as low resistance in source/drain regions, easiness in formation of a contact hole for a main electrode and stability of a silicide layer and an advantage of an FD mode MOSFET such as excellent switching characteristics are compatibly implemented.
    Type: Grant
    Filed: March 10, 1999
    Date of Patent: July 2, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigenobu Maeda, Shigeto Maegawa