Patents by Inventor Maria Chow Chan

Maria Chow Chan 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: 7012008
    Abstract: In a two-step spacer fabrication process for a non-volatile memory device, a thin oxide layer is deposited on a wafer substrate leaving a gap in the core of the non-volatile memory device. Implantation and/or oxide-nitride-oxide removal can be accomplished through this gap. After implantation, a second spacer is deposited. After the second spacer deposition, a periphery spacer etch is performed. By the above method, a spacer is formed.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: March 14, 2006
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Jeffrey A. Shields, Tuan D. Pham, Mark T. Ramsbey, Yu Sun, Angela T. Hui, Maria Chow Chan
  • Patent number: 6143608
    Abstract: This invention describes methods for producing gate oxide regions in periphery regions of semiconductor chips, wherein the gate oxide regions have improved electrical properties. The methods involve the deposition of a barrier layer over the periphery of the semiconductor chip to prevent the introduction of contaminating nitrogen atoms into the periphery during a nitridation step in the core region of the semiconductor chip. By preventing the contamination of the gate areas of the periphery, the gate oxide regions so produced have increased breakdown voltages and increased reliability. This invention describes methods for etching the barrier layers used to protect the periphery from tunnel oxide nitridation. Semiconductor devices made with the methods of this invention have longer expected lifetimes and can be manufactured with higher device density.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: November 7, 2000
    Assignees: Advanced Micro Devices, Inc., Fujitsu Limited
    Inventors: Yue-Song He, Masaaki Higashitani, Hao Fang, Narbeh Derhacobian, Bill Cox, Kent Chang, Kelwin Ko, Maria Chow-Chan
  • Patent number: 6087271
    Abstract: A method is provided for removing an bottom anti-reflective coating (BARC) from a transistor gate following at least one etch back process associated with a spacer formation and/or subsequent resistor protect etching process or processes. The method eliminates the need to use HF acid in the stripping process by substantially reducing the thickness of the BARC during each of the etching back processes, such that, only a thin layer of BARC material remains that can be easily removed with phosphoric acid.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: July 11, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventors: William G. En, Minh Van Ngo, Olov B. Karlsson, Christopher F. Lyons, Maria Chow Chan
  • Patent number: 6046085
    Abstract: A method of preventing poly stringers in the formation of a memory device includes the steps of forming at least one field oxide region in a substrate and forming a tunnel oxide over the substrate. A first polysilicon layer is then formed over the tunnel oxide and a poly mask having a mask profile is formed over the first polysilicon layer. The first polysilicon layer is then etched in portions exposed by the poly mask, thereby creating a first polysilicon layer etch profile, wherein the first polysilicon layer etch profile is substantially ideally anisotropic and independent of the mask profile. An insulating layer and a conductive layer is then formed over the etched first polysilicon layer and portions of the conductive layer are then etched to form word lines. The insulating layer is then etched in regions adjacent the word lines, thereby leaving a substantially vertical insulative fence along the first polysilicon layer etch profile.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: April 4, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Maria Chow Chan
  • Patent number: 6027959
    Abstract: A method is provided for removing an bottom anti-reflective coating (BARC) from a transistor gate during an etch back process associated with a nitride resistor protect etch process. The method includes removing a silicon oxynitride BARC, in-situ, during an oxide resistor protect etching process using a plasma formed with CF.sub.4 gas, CHF.sub.3 gas, O.sub.2 gas, and Argon (Ar) gas.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: February 22, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventors: William G. En, Minh Van Ngo, Olov B. Karlsson, Maria Chow Chan
  • Patent number: 5933729
    Abstract: A method (200) of making a flash memory device without poly stringers includes forming a stacked gate region (202) on a substrate (102) and forming one or more word lines (122a, 122b, 204) in the stacked gate region. The method further includes performing a self-aligned etch (206) in regions adjacent to the one or more word lines (122a, 122b). The self-aligned etch (206) includes etching an insulating layer (110, 206a) with a relatively high insulating layer-to-polysilicon layer selectivity to thereby reduce the height of the resultant insulative fence (126). The self-aligned etch (206) then concludes with etching a polysilicon layer (106a, 106b); due to the reduced insulative fence (126), no poly stringers are formed during the etching of the polysilicon layer (106a, 106b).
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: August 3, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Maria Chow Chan