Patents by Inventor James D. Sansbury

James D. Sansbury 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: 6828620
    Abstract: A technique of fabricating a nonvolatile device includes forming a low doping region to aid in the reduction of substrate hot electrons. The nonvolatile device may be a floating gate device, such as a Flash, EEPROM, or EPROM memory cell. The low doping region has a lower doping concentration than that of the substrate. By reducing substrate hot electrons, this improves the reliability and longevity of the nonvolatile device.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: December 7, 2004
    Assignee: Altera Corporation
    Inventors: Christopher J. Pass, James D. Sansbury, Raminda U. Madurawe, John E. Turner, Rakesh H. Patel, Peter J. Wright
  • Patent number: 6781883
    Abstract: Disclosed is a method and apparatus for evaluating margin voltages in single poly EEPROM cells. Briefly, the invention involves shifting the cell's threshold voltage higher, resulting in a corresponding rise in the margin voltage, so that testing for the erase margin may be conducted in the positive voltage range. The present invention implements a variety of solutions to the problem, including both innovations in cell processing and circuitry. In one embodiment, the process steps employed to create the floating gate transistor are changed in order to increase its threshold voltage. Alternatively, or in combination with these general process changes, the width of the floating gate transistor may be reduced, resulting in a corresponding increase in the margin voltage.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: August 24, 2004
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, Myron W. Wong, John C. Costello, James D. Sansbury, Bruce E. Mielk
  • Patent number: 6646919
    Abstract: Disclosed is a method and apparatus for evaluating margin voltages in single poly EEPROM cells. Briefly, the invention involves shifting the cell's threshold voltage higher, resulting in a corresponding rise in the margin voltage, so that testing for the erase margin may be conducted in the positive voltage range. The present invention implements a variety of solutions to the problem, including both innovations in cell processing and circuitry. In one embodiment, the process steps employed to create the floating gate transistor are changed in order to increase its threshold voltage. Alternatively, or in combination with these general process changes, the width of the floating gate transistor may be reduced, resulting in a corresponding increase in the margin voltage.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: November 11, 2003
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, Myron W. Wong, John C. Costello, James D. Sansbury, Bruce F. Mielke
  • Publication number: 20030197218
    Abstract: A technique of fabricating a nonvolatile device includes forming a low doping region to aid in the reduction of substrate hot electrons. The nonvolatile device may be a floating gate device, such as a Flash, EEPROM, or EPROM memory cell. The low doping region has a lower doping concentration than that of the substrate. By reducing substrate hot electrons, this improves the reliability and longevity of the nonvolatile device.
    Type: Application
    Filed: May 12, 2003
    Publication date: October 23, 2003
    Applicant: Altera Corporation
    Inventors: Christopher J. Pass, James D. Sansbury, Raminda U. Madurawe, John E. Turner, Rakesh H. Patel, Peter J. Wright
  • Patent number: 6573138
    Abstract: A technique of fabricating a nonvolatile device includes forming a low doping region to aid in the reduction of substrate hot electrons. The nonvolatile device may be a floating gate device, such as a Flash, EEPROM, or EPROM memory cell. The low doping region has a lower doping concentration than that of the substrate. By reducing substrate hot electrons, this improves the reliability and longevity of the nonvolatile device.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: June 3, 2003
    Assignee: Altera Corporation
    Inventors: Christopher J. Pass, James D. Sansbury, Raminda U. Madurawe, John E. Turner, Rakesh H. Patel, Peter J. Wright
  • Patent number: 6532170
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (810). In one embodiment, the programmable memory element (810) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 2, 2001
    Date of Patent: March 11, 2003
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6456529
    Abstract: A programmable impedance element (204) is implemented using integrated circuit techniques and devices. An impedance of the programmable impedance element is adjusted by appropriately configuring the element. The programmable impedance element has a range of impedance values, and is configurable to be a value within this range. In an embodiment, the programmable impedance element is implemented using a floating gate device (230), and is nonvolatile.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: September 24, 2002
    Assignee: SanDisk Corporation
    Inventors: James D. Sansbury, Sau C. Wang
  • Patent number: 6442073
    Abstract: A nonvolatile memory cell (500) has multiple oxide thicknesses, a tunnel oxide portion (625) and thicker gate oxide portion (630). The memory cell (500) may be used to form compact arrays of memory cells to store logical data. During programming of a selected memory cell, unselected memory cells are not disturbed, and oxide stress for the unselected memory cells is minimized. Techniques for operating programming, erasing, and characterizing the memory cell with multiple oxide thicknesses are discussed.
    Type: Grant
    Filed: April 10, 2001
    Date of Patent: August 27, 2002
    Assignee: Altera Corporation
    Inventor: James D. Sansbury
  • Patent number: 6366498
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: April 2, 2002
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Publication number: 20020034098
    Abstract: A programmable impedance element (204) is implemented using integrated circuit techniques and devices. An impedance of the programmable impedance element is adjusted by appropriately configuring the element. The programmable impedance element has a range of impedance values, and is configurable to be a value within this range. In an embodiment, the programmable impedance element is implemented using a floating gate device (230), and is nonvolatile.
    Type: Application
    Filed: September 27, 2001
    Publication date: March 21, 2002
    Inventors: James D. Sansbury, Sau C. Wang
  • Patent number: 6320788
    Abstract: A programmable impedance element (204) is implemented using integrated circuit techniques and devices. An impedance of the programmable impedance element is adjusted by appropriately configuring the element. The programmable impedance element has a range of impedance values, and is configurable to be a value within this range. In an embodiment, the programmable impedance element is implemented using a floating gate device (230), and is nonvolatile.
    Type: Grant
    Filed: September 11, 2000
    Date of Patent: November 20, 2001
    Assignee: Sandisk Corporation
    Inventors: James D. Sansbury, Sau C. Wang
  • Patent number: 6295230
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: September 25, 2001
    Assignee: Altera Coporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6282122
    Abstract: Techniques are used to evaluate margin of programmable memory cells. In particular, techniques are used to measure negative erased threshold voltage levels.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: August 28, 2001
    Assignee: Altera Corporation
    Inventor: James D. Sansbury
  • Patent number: 6268623
    Abstract: Disclosed is a method and apparatus for evaluating margin voltages in single poly EEPROM cells. Briefly, the invention involves shifting the cell's threshold voltage higher, resulting in a corresponding rise in the margin voltage, so that testing for the erase margin may be conducted in the positive voltage range. The present invention implements a variety of solutions to the problem, including both innovations in cell processing and circuitry. In one embodiment, the process steps employed to create the floating gate transistor are changed in order to increase its threshold voltage. Alternatively, or in combination with these general process changes, the width of the floating gate transistor may be reduced, resulting in a corresponding increase in the margin voltage.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: July 31, 2001
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, Myron W. Wong, John C. Costello, James D. Sansbury, Bruce E. Mielke
  • Patent number: 6243296
    Abstract: A nonvolatile memory cell (600) has a read device (510), program device (515), and tunnel diode (535). A write control line (WC) is directly coupled to the tunnel diode (535). The memory cell (500) may be used to form compact arrays of memory cells to store logical data. During programming of a selected memory cell, half-select voltages are used on the write control (WC) and control gate lines (CG) for unselected memory cells to prevent disturb and minimize oxide stress.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: June 5, 2001
    Assignee: Altera Corporation
    Inventor: James D. Sansbury
  • Patent number: 6236597
    Abstract: A nonvolatile memory cell (500) has multiple oxide thicknesses, a tunnel oxide portion (625) and thicker gate oxide portion (630). The memory cell (500) may be used to form compact arrays of memory cells to store logical data. During programming of a selected memory cell, unselected memory cells are not disturbed, and oxide stress for the unselected memory cells is minimized. Techniques for operating programming, erasing, and characterizing the memory cell with multiple oxide thicknesses are discussed.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: May 22, 2001
    Assignee: Altera Corporation
    Inventor: James D. Sansbury
  • Patent number: 6226201
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: May 1, 2001
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury
  • Patent number: 6201734
    Abstract: A programmable impedance element (204) is implemented using integrated circuit techniques and devices. An impedance of the programmable impedance element is adjusted by appropriately configuring the element. The programmable impedance element has a range of impedance values, and is configurable to be a value within this range. In an embodiment, the programmable impedance element is implemented using a floating gate device (230), and is nonvolatile.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: March 13, 2001
    Assignee: SanDisk Corporation
    Inventors: James D. Sansbury, Sau C. Wang
  • Patent number: 6122209
    Abstract: A static, nonvolatile, and reprogrammable programmable interconnect junction cell for implementing programmable interconnect in an integrated circuit. The programmable interconnect junction (600) is programmably configured to couple or decouple a first interconnect line (210) and a second interconnect line (220). The configured state of the programmable interconnect junction is detected directly, and memory cell detection circuitry such as sense amplifiers are not needed during normal operation. Full-rail voltages may be passed from the first interconnect line and the second interconnect line.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: September 19, 2000
    Assignee: Altera Corporation
    Inventors: Christopher J. Pass, James D. Sansbury, Raminda U. Madurawe, John E. Turner, Rakesh H. Patel, Peter J. Wright
  • Patent number: 6078521
    Abstract: A memory cell (400) used to store data in an integrated circuit. The memory cell (400) is static, nonvolatile, and programmable. The layout of the memory cell is compact. A logic high output from the memory cell (400) is about VDD and a logic low output is about VSS. The memory cell (400) of the present invention includes a programmable memory element (515). In one embodiment, the programmable memory element (515) is coupled between supply voltage (510) and an output node (405). A pull-down device (525) is coupled between another supply voltage (505) and the output node (405). The memory cell (400) may be used to store the configuration information for a programmable logic device (121).
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: June 20, 2000
    Assignee: Altera Corporation
    Inventors: Raminda U. Madurawe, James D. Sansbury