Patents by Inventor Janet S. Y. Wang

Janet S. Y. Wang 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: 6618290
    Abstract: A method of programming that includes programming a fresh memory cell with a substrate that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. Baking the programmed fresh cell causing a charge loss in the channel while the remaining charge within the channel is distributed more locally at the first region when compared to the distribution of charge prior to the baking.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: September 9, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Janet S. Y. Wang, Narbeh Derhacobian
  • Patent number: 6590811
    Abstract: A method and system for programming of the normal bits of a memory array of dual bit memory cells is accomplished by programming at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. Furthermore, by utilizing substantially high gate and drain voltages during programming, programming times are kept short without degrading charge loss. A methodology is provided that determines the charge loss for single bit operation during program and erase cycles. The charge losses over cycling and stress are then utilized to determine an appropriate delta VT to be programmed into a command logic and state machine.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: July 8, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Narbeh Derhacobian, Janet S. Y. Wang, Kulachet Tanpairoj
  • Patent number: 6567303
    Abstract: A system and methodology is provided for programming first and second bits of a memory array of dual bit memory cells at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. At a substantially higher delta VT, programming of the first bit of the memory cell causes the second bit to program harder and faster due to the shorter channel length. Therefore, the present invention employs selected gate and drain voltages and programming pulse widths during programming of the first and second bit that assures a controlled first bit VT and slows down programming of the second bit. Furthermore, the selected programming parameters keep the programming times short without degrading charge loss.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: May 20, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Janet S. Y. Wang, Narbeh Derhacobian, Tim Thurgate, Michael K. Han
  • Patent number: 6490205
    Abstract: A method of erasing a memory cell with a substrate that has a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains an initial amount of charge. The method includes applying a constant first voltage across the gate and applying a second constant voltage across said the region. A third constant voltage is applied in a region of the substrate outside of the first and second regions so that a first portion of the first amount of charge is removed from the charge trapping region.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: December 3, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Janet S. Y. Wang, Ravi S. Sunkavalli
  • Publication number: 20020159293
    Abstract: A method and system for programming of the normal bits of a memory array of dual bit memory cells is accomplished by programming at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. Furthermore, by utilizing substantially high gate and drain voltages during programming, programming times are kept short without degrading charge loss. A methodology is provided that determines the charge loss for single bit operation during program and erase cycles. The charge losses over cycling and stress are then utilized to determine an appropriate delta VT to be programmed into a command logic and state machine.
    Type: Application
    Filed: February 28, 2001
    Publication date: October 31, 2002
    Inventors: Darlene G. Hamilton, Narbeh Derhacobian, Janet S. Y. Wang, Kulachet Tanpairoj
  • Patent number: 6459618
    Abstract: A method of programming a memory cell with a substrate that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes applying a constant first voltage across the gate and applying a second constant voltage across the first region so as to generate a first charge injection region. The application of the second constant voltage is discontinued while simultaneously applying a third constant voltage across the first region so that a second charge injection region is generated that is larger than the first charge injection region.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: October 1, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Janet S. Y. Wang
  • Patent number: 6456533
    Abstract: A method and system for programming of the normal bits of a memory array of dual bit memory cells is accomplished by programming at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. Furthermore, by utilizing substantially high gate and drain voltages during programming, programming times are kept short without degrading charge loss. A methodology is provided that determines the charge loss for single bit operation during program and erase cycles. The charge losses over cycling and stress are then utilized to determine an appropriate delta VT to be programmed into a command logic and state machine.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: September 24, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Narbeh Derhacobian, Janet S.Y. Wang, Kulachet K.T. Tanpairoj
  • Patent number: 6456531
    Abstract: A method of programming a memory cell with a substrate that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes applying a constant first voltage across the gate, applying a second constant voltage across the first region, and applying a third constant voltage across the second region that is near the avalanche breakdown voltage of the second region so that spillover electrons are significantly reduced in number within the channel when compared to if the third constant voltage is well below the avalanche breakdown voltage.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: September 24, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Janet S. Y. Wang, Sameer S. Haddad
  • Patent number: 6331953
    Abstract: A method of erasing a memory cell that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes: applying a voltage across the gate and the first region in accordance with a coarse erase sequence of voltages so that a portion of the first amount of charge is removed from the charge trapping region; and applying a voltage across the gate and the first region in accordance with a fine erase sequence of voltages so that a portion of the first amount of charge is removed from the charge trapping region.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: December 18, 2001
    Assignee: Advanced Micro Devices
    Inventors: Janet S. Y. Wang, Narbeh Derhacobian, Daniel Sobek
  • Patent number: 6331952
    Abstract: A method of erasing a memory cell that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes simultaneously applying a first positive voltage across the gate and a second positive voltage to the first region, wherein the second positive voltage is greater than the first positive voltage.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: December 18, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Janet S. Y. Wang, Narbeh Derhacobian, Ravi S. Sunkavalli
  • Patent number: 6269023
    Abstract: A memory cell that includes a substrate that has a first region and a second region with a channel therebetween, wherein the first region generates hot carriers. The memory cell further includes a gate above the channel and a charge trapping region that contains a first amount of charge. A current limiter that limits the number of the generated hot carriers that can flow into the channel, wherein the current limiter does not control the voltage of the second region.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: July 31, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Narbeh Derhacobian, Janet S. Y. Wang, Daniel Sobek, Sameer S. Haddad
  • Patent number: 6266281
    Abstract: A method of erasing a memory cell that has a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains an initial amount of charge. The method includes applying a first voltage across the gate and the first region so that a first portion of the initial amount of charge is removed from the charge trapping region. Next, a second voltage is applied across the gate and the first region so that a second portion of the initial amount of charge is removed from the charge trapping region, wherein the second voltage is different than the first voltage.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: July 24, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Narbeth Derhacobian, Michael Van Buskirk, Daniel Sobeck, Janet S. Y. Wang, Chi Chang