Patents by Inventor Wipawan Yindeepol

Wipawan Yindeepol 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: 6979879
    Abstract: In a zener zap diode device and a system for making such a device using a double poly process, p+ and n+regions are formed in a tub by means of p-doped and n-doped polysilicon regions, and a p-n junction is formed between the p+ region and an n-tub or between the n+ region and a p-tub. Cobalt or other refractory metal is reacted with silicon to form a silicide on at least the p-doped polysilicon region. By reverse biasing the p-n junction and establishing a sufficiently high zap current, the silicide can be forced to migrate across the junction to form a silicide bridge thereby selectively shorting out the p-n junction.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: December 27, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Wipawan Yindeepol, Andy Strachan
  • Patent number: 6362064
    Abstract: Walkout in high voltage trench isolated semiconductor devices is inhibited by applying a voltage bias signal directly to epitaxial silicon surrounding the device. Voltage applied to the surrounding epitaxial silicon elevates the initial breakdown voltage of the device and eliminates walkout. This is because voltage applied to the surrounding epitaxial silicon reduces the strength of the electric field between the silicon of the device and the surrounding silicon. Specifically, application of a positive voltage bias signal to surrounding epitaxial silicon equal to or more positive than the most positive potential occurring at the collector during normal operation of the device ensures that no walkout will occur.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: March 26, 2002
    Assignee: National Semiconductor Corporation
    Inventors: Joel M. McGregor, Rashid Bashir, Wipawan Yindeepol
  • Publication number: 20010023974
    Abstract: Walkout in high voltage trench isolated semiconductor devices is inhibited by applying a voltage bias signal directly to epitaxial silicon surrounding the device. Voltage applied to the surrounding epitaxial silicon elevates the initial breakdown voltage of the device and eliminates walkout. This is because voltage applied to the surrounding epitaxial silicon reduces the strength of the electric field between the silicon of the device and the surrounding silicon. Specifically, application of a positive voltage bias signal to surrounding epitaxial silicon equal to or more positive than the most positive potential occurring at the collector during normal operation of the device ensures that no walkout will occur.
    Type: Application
    Filed: April 21, 1998
    Publication date: September 27, 2001
    Inventors: JOEL M. MCGREGOR, RASHID BASHIR, WIPAWAN YINDEEPOL
  • Patent number: 6121148
    Abstract: A semiconductor device, polysilicon-contacted trench isolation structure that provides improved electrical isolation stability, a method of operating a polysilicon-contacted trench isolated semiconductor device, and a process for manufacturing a polysilicon-contacted trench isolation structure. The trench isolation structure includes an isolation trench formed in a semiconductor substrate. The isolation trench has a layer of trench lining oxide, a layer of trench lining silicon nitride and a trench fill polysilicon (poly 1) layer. Exposed lateral surfaces of the poly 1, which extend above the trench lining silicon nitride, are contacted to another layer of polysilicon (poly 2). The method of operation includes applying a bias voltage to the trench fill poly 1 layer via poly 2. The process for manufacture includes etching an isolation trench that extends through a layer of field oxide and into a semiconductor substrate.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: September 19, 2000
    Assignee: National Semiconductor Corporation
    Inventors: Rashid Bashir, Wipawan Yindeepol
  • Patent number: 5914523
    Abstract: A semiconductor device, polysilicon-contacted trench isolation- structure that provides improved electrical isolation stability, a method of operating a polysilicon-contacted trench isolated semiconductor device, and a process for manufacturing a polysilicon-contacted trench isolation structure. The trench isolation structure includes an isolation trench formed in a semiconductor substrate. The isolation trench has a layer of trench lining oxide, a layer of trench lining silicon nitride and a trench fill polysilicon (poly 1) layer. Exposed lateral surfaces of the poly 1, which extend above the trench lining silicon nitride, are contacted to another layer of polysilicon (poly 2). The method of operation includes applying a bias voltage to the trench fill poly 1 layer via poly 2. The process for manufacture includes etching an isolation trench that extends through a layer of field oxide and into a semiconductor substrate.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: June 22, 1999
    Assignee: National Semiconductor Corp.
    Inventors: Rashid Bashir, Wipawan Yindeepol
  • Patent number: 5911109
    Abstract: A trench which has walls intersecting a surface of a semiconductor substrate and an oxidation/diffusion barrier layer lining the walls is disclosed. The oxidation/diffusion barrier extends over the edges of the trench to prevent, for example, stress defects in the trench corners and vertical bird's beak formation within the trench. A filler material such as polysilicon is deposited within the trench followed by the deposition of a planarizing layer over the trench. After heat is applied, the planarizing layer flows to form a planarized layer over the trench. Using high pressure and phosphosilicate glass for the planarizing layer, the planarizing layer flows appropriately at low temperatures for short times.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: June 8, 1999
    Assignee: National Semiconductor Corporation
    Inventors: Reda R. Razouk, Kulwant S. Egan, Wipawan Yindeepol, Waclaw C. Koscielniak
  • Patent number: 5811315
    Abstract: A method of forming and planarizing a deep isolation trench in a silicon-on-insulator (SOI) structure begins with a base semiconductor substrate, a buried insulator layer formed on the base semiconductor substrate, and an active silicon layer formed on the buried insulator layer. First, an ONO layer is formed on the active silicon layer. The ONO layer includes a layer of field oxide, a first layer of silicon nitride and a layer of deposited hardmask oxide. A trench having sidewalls that extend to the buried oxide layer is formed. A layer of trench lining oxide is then formed on the exposed sidewalls of the trench. Then, a second layer of silicon nitride is conformally formed on the substrate.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: September 22, 1998
    Assignee: National Semiconductor Corporation
    Inventors: Wipawan Yindeepol, Joel McGregor, Rashid Bashir, Kevin Brown, Joseph Anthony DeSantis
  • Patent number: 5581110
    Abstract: A trench which has walls intersecting a surface of a semiconductor substrate and an oxidation/diffusion barrier layer lining the walls is disclosed. The oxidation/diffusion barrier extends over the edges of the trench to prevent, for example, stress defects in the trench corners and vertical bird's beak formation within the trench. A filler material such as polysilicon is deposited within the trench followed by the deposition of a planarizing layer over the trench. After heat is applied, the planarizing layer flows to form a planarized layer over the trench. Using high pressure and phosphosilicate glass for the planarizing layer, the planarizing layer flows appropriately at low temperatures for short times.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: December 3, 1996
    Assignee: National Semiconductor Corporation
    Inventors: Reda R. Razouk, Kulwant S. Egan, Wipawan Yindeepol, Waclaw C. Koscielniak