Patents by Inventor Fred T K Cheung

Fred T K Cheung 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: 9461151
    Abstract: An embodiment of the present invention is directed to a memory cell. The memory cell includes a first charge storage element and a second charge storage element, wherein the first and second charge storage elements include nitrides. The memory cell further includes an insulating layer formed between the first and second charge storage elements. The insulating layer provides insulation between the first and second charge storage elements.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: October 4, 2016
    Assignee: CYRESS SEMICONDUCTOR CORPORATION
    Inventors: Fred T. K. Cheung, Hiroyuki Kinoshita, Chungho Lee, Yu Sun, Chi Chang
  • Patent number: 7163860
    Abstract: The present invention, in one embodiment, relates to a process for fabricating a charge trapping dielectric flash memory device including steps of providing a semiconductor substrate having formed thereon a gate stack comprising a charge trapping dielectric charge storage layer and a control gate electrode overlying the charge trapping dielectric charge storage layer; forming an oxide layer over at least the gate stack; and depositing a spacer layer over the gate stack, wherein the depositing step deposits a spacer material having a reduced hydrogen content relative to a hydrogen content of a conventional spacer material.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: January 16, 2007
    Assignee: Spansion LLC
    Inventors: Tazrien Kamal, Yun Wu, Mark Ramsbey, Jean Yee-Mei Yang, Arvind Halliyal, Rinji Sugino, Hidehiko Shiraiwa, Fred T K Cheung
  • Patent number: 7033957
    Abstract: Process for reducing charge leakage in a SONOS flash memory device, including in one embodiment, forming a bottom oxide layer of an ONO structure on the semiconductor substrate to form an oxide/silicon interface having a first oxygen content adjacent the oxide/silicon interface; treating the bottom oxide layer to increase the first oxygen content to a second oxygen content adjacent the oxide/silicon interface; and depositing a nitride charge-storage layer on the bottom oxide layer. In another embodiment, process for reducing charge leakage in a SONOS flash memory device, including forming a bottom oxide layer of an ONO structure on a surface of the semiconductor substrate having an oxide/silicon interface with a super-stoichiometric oxygen content adjacent the oxide/silicon interface; and depositing a nitride charge-storage layer on the bottom oxide layer.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: April 25, 2006
    Assignee: FASL, LLC
    Inventors: Hidehiko Shiraiwa, Tazrien Kamal, Mark Ramsbey, Inkuk Kang, Jaeyong Park, Rinji Sugino, Jean Y. Yang, Fred T K Cheung, Arvind Halliyal, Amir H. Jafarpour
  • Patent number: 6949481
    Abstract: Process for fabricating a semiconductor device including steps of providing a semiconductor substrate having formed thereon a semiconductor device; depositing over the semiconductor device a spacer layer, the spacer layer having a first hydrogen content; and applying a treatment to reduce the first hydrogen content to a second hydrogen content. The invention is particularly useful when applied to flash memory devices such as a charge trapping dielectric flash memory device.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: September 27, 2005
    Assignee: FASL, LLC
    Inventors: Arvind Halliyal, Fred T K Cheung, Rinji Sugino, Hidehiko Shiraiwa, Tazrien Kamal, Jean Y. Yang
  • Patent number: 6794764
    Abstract: The present invention relates to a memory array comprising a substrate and a plurality of bitlines having contacts and a plurality of wordlines intersecting the bitlines. A protective spacer is used to separate the bitline contacts from the wordlines adjacent to the bitline contacts to prevent damage caused during the formation of the bitline contacts. The present invention also relates to a method of forming the memory array.
    Type: Grant
    Filed: March 5, 2003
    Date of Patent: September 21, 2004
    Assignees: Advanced Micro Devices, Inc., Fujitsu Limited
    Inventors: Tazrien Kamal, Mark T. Ramsbey, Hidehiko Shiraiwa, Fred T K Cheung
  • Patent number: 6740605
    Abstract: The present invention, in one embodiment, relates to a process for fabricating a semiconductor device that is less susceptible to performance degradation caused by hydrogen contamination. The method includes the steps for removing unwanted hydrogen bonds by exposing the hydrogen bonds to ultraviolet radiation sufficient to break the bond and annealing in an atmosphere comprising at least one gas having at least one atom capable of forming bonds that replace the hydrogen bonds.
    Type: Grant
    Filed: May 5, 2003
    Date of Patent: May 25, 2004
    Assignees: Advanced Micro Devices, Inc., Fujitsu Limited
    Inventors: Hidehiko Shiraiwa, Jaeyong Park, Fred T K Cheung, Arvind Halliyal
  • Patent number: 6735123
    Abstract: A dual bit dielectric memory cell comprises a substrate with a source region and a drain region implanted on opposing sides of a central channel region. A multilevel charge trapping dielectric is positioned on the substrate above the central channel region and includes a central region between an opposing source lateral region and a drain lateral region. A control gate is positioned above the multilevel charge trapping dielectric. The multilevel charge trapping dielectric comprises a tunnel dielectric layer adjacent the substrate, a top dielectric adjacent the control gate, and a charge trapping dielectric positioned there between. The thickness of the tunnel dielectric layer in the central region is greater than a thickness of the tunnel dielectric layer in each of the source lateral region and the drain lateral region.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: May 11, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Nicholas H. Tripsas, Mark T. Ramsbey, Wei Zheng, Effiong Ibok, Fred T K Cheung
  • Patent number: 6642573
    Abstract: A process for fabrication of a semiconductor device including a modified ONO structure, comprising forming the modified ONO structure by providing a semiconductor substrate; forming a first dielectric material layer on the semiconductor substrate; depositing a silicon nitride layer on the first dielectric material layer; and forming a top dielectric material layer, wherein at least one of the bottom dielectric material layer and the top dielectric material layer comprise a mid-K or a high-K dielectric material. The semiconductor device may be, e.g., a SONOS two-bit EEPROM device or a floating gate flash device including the modified ONO structure.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: November 4, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Arvind Halliyal, Mark T. Ramsbey, Wei Zhang, Mark W. Randolph, Fred T. K. Cheung
  • Patent number: 6630383
    Abstract: In one embodiment, a method of making a gate stack semiconductor device is disclosed. The method comprises the steps of: forming a tunnel oxide layer over a p-type semiconductor substrate; forming a floating gate over the tunnel oxide layer by first forming an n-type polysilicon layer and subjecting the n-type polysilicon layer to nitridation, and then forming a p-type polysilicon layer over the nitridated n-type polysilicon layer; and forming a high-K insulating layer over the p-type polysilicon layer.
    Type: Grant
    Filed: October 17, 2002
    Date of Patent: October 7, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Effiong Ibok, Wei Zheng, Nicholas H. Tripsas, Mark T. Ramsbey, Fred T K Cheung