Patents by Inventor Hisashi Shichijo

Hisashi Shichijo 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: 8134204
    Abstract: A drain extended MOS (DEMOS) transistor with an element of field oxide separating the drain contact from the gate, and a compensation region of opposite polarity in the drain under the gate, is disclosed. The inventive DEMOS may be fabricated in a CMOS IC without adding any process steps. Both n-channel and p-channel versions may be fabricated in CMOS ICs with an n-type buried layer. Furthermore, the inventive transistor may be fabricated in an IC built in an SOI wafer. The width of the compensation region may be varied across multiple instances of the inventive DEMOS transistor to provide a capability for handling multiple signals with different voltage levels in the same IC without adding fabrication steps. The compensation region may be biased by a control voltage to modulate the depletion of the drain extension and provide a capability for handling multiple signal voltage levels in a single transistor.
    Type: Grant
    Filed: August 6, 2009
    Date of Patent: March 13, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Kamel Benaissa, Hisashi Shichijo
  • Patent number: 7915905
    Abstract: In an apparatus and method for monitoring defects in wafers, a monitoring circuit is fabricated on an area of each one of the wafers. The monitoring circuit includes representative devices that replicate similar devices located in a die area of the wafers. Defects if present in the representative devices contribute to a generation of a noise, thereby causing an imbalance in a differential signal measurable across selected ones of the representative devices. A digitizing circuit that uses a common mode voltage as a reference to measure the imbalance digitizes the differential signal to a digital signal, the digital signal being indicative of the noise generated by the defects. The digital signal is stored over a configurable time interval to form a digital bit stream. The digital bit stream is compared to a reference to determine whether the defeats are within an allowable range.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: March 29, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Baher S. Haroun, Gaurav Chandra, Vijaya Bhaskar Rentala, Venkatesh Srinivasan, Hisashi Shichijo, Krishnaswamy Nagaraj
  • Publication number: 20100197053
    Abstract: In an apparatus and method for monitoring defects in wafers, a monitoring circuit is fabricated on an area of each one of the wafers. The monitoring circuit includes representative devices that replicate similar devices located in a die area of the wafers. Defects if present in the representative devices contribute to a generation of a noise, thereby causing an imbalance in a differential signal measurable across selected ones of the representative devices. A digitizing circuit that uses a common mode voltage as a reference to measure the imbalance digitizes the differential signal to a digital signal, the digital signal being indicative of the noise generated by the defects. The digital signal is stored over a configurable time interval to form a digital bit stream. The digital bit stream is compared to a reference to determine whether the defeats are within an allowable range.
    Type: Application
    Filed: April 16, 2010
    Publication date: August 5, 2010
    Inventors: Baher S. Haroun, Gaurav Chandra, Vijaya Bhaskar Rentala, Venkatesh Srinivasan, Hisashi Shichijo, Krishnaswamy Nagaraj
  • Patent number: 7719299
    Abstract: In an apparatus and method for monitoring defects in wafers, a monitoring circuit is fabricated on an area of each one of the wafers. The monitoring circuit includes representative devices that replicate similar devices located in a die area of the wafers. Defects if present in the representative devices contribute to a generation of a noise, thereby causing an imbalance in a differential signal measurable across selected ones of the representative devices. A digitizing circuit that uses a common mode voltage as a reference to measure the imbalance digitizes the differential signal to a digital signal, the digital signal being indicative of the noise generated by the defects. The digital signal is stored over a configurable time interval to form a digital bit stream. The digital bit stream is compared to a reference to determine whether the defects are within an allowable range.
    Type: Grant
    Filed: April 2, 2008
    Date of Patent: May 18, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Baher S. Haroun, Gaurav Chandra, Vijaya Bhaskar Rentala, Venkatesh Srinivasan, Hisashi Shichijo, Krishnaswamy Nagaraj
  • Patent number: 7692217
    Abstract: One embodiment of the invention relates to an integrated circuit. The integrated circuit includes a first matched transistor comprising: a first source region, a first drain region formed within a first drain well extension, and a first gate electrode having lateral edges about which the first source region and first drain region are laterally disposed. The integrated circuit also includes a second matched transistor comprising: a second source region, a second drain region formed within a second drain well extension, and a second gate electrode having lateral edges about which the second source region and second drain region are laterally disposed. Analog circuitry is associated with the first and second matched transistors, which analog circuitry utilizes a matching characteristic of the first and second matched transistors to facilitate analog functionality. Other devices, methods, and systems are also disclosed.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: April 6, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Henry Litzmann Edwards, Hisashi Shichijo, Tathagata Chatterjee, Shyh-Horng Yang, Lance Stanford Robertson
  • Publication number: 20100032755
    Abstract: A drain extended MOS (DEMOS) transistor with an element of field oxide separating the drain contact from the gate, and a compensation region of opposite polarity in the drain under the gate, is disclosed. The inventive DEMOS may be fabricated in a CMOS IC without adding any process steps. Both n-channel and p-channel versions may be fabricated in CMOS ICs with an n-type buried layer. Furthermore, the inventive transistor may be fabricated in an IC built in an SOI wafer. The width of the compensation region may be varied across multiple instances of the inventive DEMOS transistor to provide a capability for handling multiple signals with different voltage levels in the same IC without adding fabrication steps. The compensation region may be biased by a control voltage to modulate the depletion of the drain extension and provide a capability for handling multiple signal voltage levels in a single transistor.
    Type: Application
    Filed: August 6, 2009
    Publication date: February 11, 2010
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Kamel BENAISSA, Hisashi SHICHIJO
  • Publication number: 20090251164
    Abstract: In an apparatus and method for monitoring defects in wafers, a monitoring circuit is fabricated on an area of each one of the wafers. The monitoring circuit includes representative devices that replicate similar devices located in a die area of the wafers. Defects if present in the representative devices contribute to a generation of a noise, thereby causing an imbalance in a differential signal measurable across selected ones of the representative devices. A digitizing circuit that uses a common mode voltage as a reference to measure the imbalance digitizes the differential signal to a digital signal, the digital signal being indicative of the noise generated by the defects. The digital signal is stored over a configurable time interval to form a digital bit stream. The digital bit stream is compared to a reference to determine whether the defects are within an allowable range.
    Type: Application
    Filed: April 2, 2008
    Publication date: October 8, 2009
    Inventors: Baher S. Haroun, Gaurav Chandra, Vijaya Bhaskar Rentala, Venkatesh Srinivasan, Hisashi Shichijo, Krishnaswamy Nagaraj
  • Publication number: 20090140346
    Abstract: One embodiment of the invention relates to an integrated circuit. The integrated circuit includes a first matched transistor comprising: a first source region, a first drain region formed within a first drain well extension, and a first gate electrode having lateral edges about which the first source region and first drain region are laterally disposed. The integrated circuit also includes a second matched transistor comprising: a second source region, a second drain region formed within a second drain well extension, and a second gate electrode having lateral edges about which the second source region and second drain region are laterally disposed. Analog circuitry is associated with the first and second matched transistors, which analog circuitry utilizes a matching characteristic of the first and second matched transistors to facilitate analog functionality. Other devices, methods, and systems are also disclosed.
    Type: Application
    Filed: November 30, 2007
    Publication date: June 4, 2009
    Inventors: Henry Litzmann Edwards, Hisashi Shichijo, Tathagata Chatterjee, Shyh-Horng Yang, Lance Stanford Robertson
  • Patent number: 7250334
    Abstract: A method (10) of forming a MIM (metal insulator metal) capacitor is disclosed whereby adverse affects associated with copper diffusion are mitigated even as the capacitor is scaled down. A sidewall spacer (156) is formed against an edge (137) of a layer of bottom electrode/copper diffusion barrier material (136), an edge (151) of a layer of capacitor dielectric material (150) and at least some of an edge (153) of a layer of top electrode material. The sidewall spacer (156) is dielectric or non-conductive and mitigates “shorting” currents that can develop between the plates as a result of copper diffusion. Bottom electrode diffusion barrier material (136) mitigates copper diffusion and/or copper drift, thereby reducing the likelihood of premature device failure.
    Type: Grant
    Filed: July 31, 2004
    Date of Patent: July 31, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Darius L. Crenshaw, Byron L. Williams, Alwin Tsao, Hisashi Shichijo, Satyavolu S. Papa Rao, Kenneth D. Brennan, Steven A. Lytle
  • Publication number: 20060024899
    Abstract: A method (10) of forming a MIM (metal insulator metal) capacitor is disclosed whereby adverse affects associated with copper diffusion are mitigated even as the capacitor is scaled down. A sidewall spacer (156) is formed against an edge (137) of a layer of bottom electrode/copper diffusion barrier material (136), an edge (151) of a layer of capacitor dielectric material (150) and at least some of an edge (153) of a layer of top electrode material. The sidewall spacer (156) is dielectric or non-conductive and mitigates “shorting” currents that can develop between the plates as a result of copper diffusion. Bottom electrode diffusion barrier material (136) mitigates copper diffusion and/or copper drift, thereby reducing the likelihood of premature device failure.
    Type: Application
    Filed: July 31, 2004
    Publication date: February 2, 2006
    Inventors: Darius Crenshaw, Byron Williams, Alwin Tsao, Hisashi Shichijo, Satyavolu Papa Rao, Kenneth Brennan, Steven Lytle
  • Patent number: 6764892
    Abstract: A semiconductor circuit for multi-voltage operation having built-in electrostatic discharge (ESD) protection is described, comprising a drain extended nMOS transistor and a pnpn silicon controlled rectifier (SCR) merged with the transistor so that a dual npn structure is created and both the source of the transistor and the cathode of the SCR are connected to electrical ground potential, forming a dual cathode, whereby the ESD protection is enhanced. The rectifier has a diffusion region, forming an abrupt junction, resistively coupled to the drain, whereby the electrical breakdown-to-substrate of the SCR can be triggered prior to the breakdown of the nMOS transistor drain. The SCR has anode and cathode regions spaced apart by semiconductor surface regions and insulating layers positioned over the surface regions with a thickness suitable for high voltage operation and ESD protection.
    Type: Grant
    Filed: May 27, 2003
    Date of Patent: July 20, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: Keith E. Kunz, Charvaka Duvvury, Hisashi Shichijo
  • Patent number: 6753202
    Abstract: A method for the fabrication of a light-sensing diode in a high-resistivity semiconductor substrate. A high-energy implant of ions into the substrate is patterned to form an annular well of the same conductivity type as the substrate; followed by a second high-energy implant of the opposite conductivity type, within the center of the annulus; followed by a third implant, of lower energy and high dosage, to form a region of the first conductivity type extending laterally near the substrate surface. The resulting diode junction is thereby patterned to include two planes near the substrate surface, allowing incident light to traverse the junction twice.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: June 22, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Publication number: 20030230704
    Abstract: A light-sensing diode in a high resistivity semiconductor substrate of a first conductivity type, the substrate having a surface protected by an insulator, comprising
    Type: Application
    Filed: May 28, 2003
    Publication date: December 18, 2003
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Publication number: 20030222273
    Abstract: A semiconductor circuit for multi-voltage operation having built-in electrostatic discharge (ESD) protection is described, comprising a drain extended nMOS transistor and a pnpn silicon controlled rectifier (SCR) merged with the transistor so that a dual npn structure is created and both the source of the transistor and the cathode of the SCR are connected to electrical ground potential, forming a dual cathode, whereby the ESD protection is enhanced. The rectifier has a diffusion region, forming an abrupt junction, resistively coupled to the drain, whereby the electrical breakdown-to-substrate of the SCR can be triggered prior to the breakdown of the nMOS transistor drain. The SCR has anode and cathode regions spaced apart by semiconductor surface regions and insulating layers positioned over the surface regions with a thickness suitable for high voltage operation and ESD protection.
    Type: Application
    Filed: May 27, 2003
    Publication date: December 4, 2003
    Inventors: Keith E. Kunz, Charvaka Duvvury, Hisashi Shichijo
  • Patent number: 6621064
    Abstract: A light-sensing diode having improved efficiency due to an extended junction geometry that provides more than one level of interaction with the light input.
    Type: Grant
    Filed: May 3, 2001
    Date of Patent: September 16, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Patent number: 6576959
    Abstract: A semiconductor circuit for multi-voltage operation having built-in electrostatic discharge (ESD) protection is described, comprising a drain extended nMOS transistor and a pnpn silicon controlled rectifier (SCR) merged with the transistor so that a dual npn structure is created and both the source of the transistor and the cathode of the SCR are connected to electrical ground potential, forming a dual cathode, whereby the ESD protection is enhanced. The rectifier has a diffusion region, forming an abrupt junction, resistively coupled to the drain, whereby the electrical breakdown-to-substrate of the SCR can be triggered prior to the breakdown of the nMOS transistor drain. The SCR has anode and cathode regions spaced apart by semiconductor surface regions and insulating layers positioned over the surface regions with a thickness suitable for high voltage operation and ESD protection.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: June 10, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Keith E. Kunz, Charvaka Duvvury, Hisashi Shichijo
  • Patent number: 6512280
    Abstract: A light-sensing diode fabricated in a semiconductor substrate having a surface protected by an insulator, comprising a first region of one conductivity type in this substrate, a second region of the opposite conductivity type forming a junction with the first region in the substrate; this junction having a convoluted shape, providing two portions generally parallel to the surface, and a constricted intersection with the surface; and a gate for applying electrical bias across the junction, this gate positioned on the insulator such that it covers all portions of the junction intersection with the surface, thereby creating a gate-controlled photodiode.
    Type: Grant
    Filed: May 16, 2001
    Date of Patent: January 28, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Publication number: 20020171097
    Abstract: A light-sensing diode fabricated in a semiconductor substrate having a surface protected by an insulator, comprising a first region of one conductivity type in this substrate, a second region of the opposite conductivity type forming a junction with the first region in the substrate; this junction having a convoluted shape, providing two portions generally parallel to the surface, and a constricted intersection with the surface; and a gate for applying electrical bias across the junction, this gate positioned on the insulator such that it covers all portions of the junction intersection with the surface, thereby creating a gate-controlled photodiode.
    Type: Application
    Filed: May 16, 2001
    Publication date: November 21, 2002
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Publication number: 20020162945
    Abstract: A light-sensing diode in a high resistivity semiconductor substrate of a first conductivity type, the substrate having a surface protected by an insulator, comprising
    Type: Application
    Filed: May 3, 2001
    Publication date: November 7, 2002
    Inventors: Zhiliang J. Chen, Kuok Y. Ling, Hisashi Shichijo, Katsuo Komatsuzaki, Chin-Yu Tsai
  • Publication number: 20020145164
    Abstract: A semiconductor circuit for multi-voltage operation having built-in electrostatic discharge (ESD) protection is described, comprising a drain extended nMOS transistor and a pnpn silicon controlled rectifier (SCR) merged with the transistor so that a dual npn structure is created and both the source of the transistor and the cathode of the SCR are connected to electrical ground potential, forming a dual cathode, whereby the ESD protection is enhanced. The rectifier has a diffusion region, forming an abrupt junction, resistively coupled to the drain, whereby the electrical breakdown-to-substrate of the SCR can be triggered prior to the breakdown of the nMOS transistor drain. The SCR has anode and cathode regions spaced apart by semiconductor surface regions and insulating layers positioned over the surface regions with a thickness suitable for high voltage operation and ESD protection.
    Type: Application
    Filed: September 5, 2001
    Publication date: October 10, 2002
    Inventors: Keith E. Kunz, Charvaka Duvvury, Hisashi Shichijo